January 08, 2017 9:48 AM

Finding a Balance Between Teaching and Doing

In the Paris Review's The Art of Fiction No. 183, the interviewer asks Tobias Wolff how he balances writing with university teaching. Wolff figures that teaching is a pretty good deal:

When I think about the kinds of jobs I've had and the ways I've lived, and still managed to get work done--my God, teaching in a university looks like easy street. I like talking about books, and I like encountering other smart, passionate readers, and feeling the friction of their thoughts against mine. Teaching forces me to articulate what otherwise would remain inchoate in my thoughts about what I read. I find that valuable, to bring things to a boil.

That reflects how I feel, too, as someone who loves to do computer science and write programs. As a teacher, I get to talk about cool ideas every day with my students, to share what I learn as I write software, and to learn from them as they ask the questions I've stopped asking myself. And they pay me. It's a great deal, perhaps the optimal point in the sort of balance that Derek Sivers recommends.

Wolff immediately followed those sentences with a caution that also strikes close to home:

But if I teach too much it begins to weigh on me--I lose my work. I can't afford to do that anymore, so I keep a fairly light teaching schedule.

One has to balance creative work with the other parts of life that feed the work. Professors at research universities, such as Wolff at Stanford, have different points of equilibrium available to them than profs at teaching universities, where course loads are heavier and usually harder to reduce.

I only teach one course a semester, which really does help me to focus creative energies around a smaller set of ideas than a heavier load does. Of course, I also have the administrative duties of a department head. They suffocate time and energy in a much less productive way than teaching does. (That's the subject of another post.)

Why can't Wolff afford to teach too many courses anymore? I suspect the answer is time. When you reach a certain age, you realize that time is no longer an ally. There are only so many years left, and Wolff probably feels the need to write more urgently. This sensation has been seeping into my mind lately, too, though I fear perhaps a bit too slowly.


(I previously quoted Wolff from the same interview in a recent entry about writers who give advice that reminds us that there is no right way to write all programs. A lot of readers seemed to like that one.)

Posted by Eugene Wallingford | Permalink | Categories: Computing, Personal, Teaching and Learning

January 06, 2017 4:29 PM

Moving a Flatter Email Archive

I'm not a New Year's resolution person, but I did make a change recently that moved me out of my comfort zone. Here's a quick version of the story.

I'm a hierarchical guy, like a lot of computer scientists, I imagine. That helps me manage a lot of complexity, but sometimes it also consumes more personal time than I'd like.

I'm also a POP mail guy. For many years, Eudora was my client of choice. A while back, I switched to Mail.app on OS X. In both, I had an elaborate filing system in which research mail was kept in a separate folder from teaching mail, which was kept in a separate folder from personal was kept in a separate folder from .... There were a dozen or so top-level folders, each having sub-folders.

Soon after I became department head a decade or so ago, I began to experience the downsides of this approach as much as the upsides. Some messages wanted to live in two folders, but I had to choose one. Even when the choice was easy, I found myself spending too many minutes each week filing away messages I would likely never think of again.

For years now, my browser- and cloud-loving friends have been extolling to me the value of leaving all my mail on the server, hitting 'archive' when I wanted to move a message out of my inbox, and then using the mail client's search feature to find messages when I need them later. I'm not likely to become a cloud email person any time soon, but the cost in time and mental energy of filing messages hierarchically finally became annoying enough that I decided to move into the search era.

January 1 was the day.

But I wasn't ready to go all the way. (Change is hard!) I'd still like to have a gross separation of personal mail from professional mail, and gross separation among email related to teaching, research, professional work, and university administration. If Mail.app had tags or labels, I might use them, but it doesn't. At this point, I have five targeted archive folders:

  • department business (I'm chair)
  • university business
  • TPLoP business (I'm a regional editor)
  • correspondence with my wife and daughters
  • other personal correspondence
  • personal finance and commerce
a folder for the course I am currently teaching, a folder for bulk mail and unavoidable mailing lists, and a folder for everything else. Everything else includes messages from mailing lists I choose to be on, such as the Racket users listserv and personal lists. None of these has subfolders.

I still have three other small hierarchies. The first is where I keep folders for other courses I have taught or plan to teach. I like the idea of keeping course questions and materials easy to find. The second is for hot topics I am working on as department head. For instance, we are currently doing a lot of work on outcomes assessment, and it's helpful to have all those messages in a separate bin. When a topic is no longer hot, I'll transfer its messages to the department archive. The third is is a set of two or three small to-do boxes. Again, it's helpful to an organizer like me to have such messages in a separate bin so that I can find and respond to them quickly; eventually those messages will move to the appropriate flat archive.

Yes, there is still a lot going on here, but it's a big change for me. So far, so good. I've not felt any urges to create subfolders yet, and I've used search to find things when I've needed them. After I become habituated to this new way of living, perhaps I'll feel daring enough to go even flatter.

Let's not talk about folders in my file system, though. Hierarchy reigns supreme there, as it always has.

Posted by Eugene Wallingford | Permalink | Categories: General, Personal

November 27, 2016 10:26 AM

Good Teaching Is Grounded In Generosity Of Spirit

In My Writing Education: A Time Line, George Saunders recounts stories of his interactions with writing teachers over the years, first in the creative writing program at Syracuse and later as a writer and teacher himself. Along the way, he shows us some of the ways that our best teachers move us.

Here, the teacher gets a bad review:

Doug gets an unkind review. We are worried. Will one of us dopily bring it up in workshop? We don't. Doug does. Right off the bat. He wants to talk about it, because he feels there might be something in it for us. The talk he gives us is beautiful, honest, courageous, totally generous. He shows us where the reviewer was wrong -- but also where the reviewer might have gotten it right. Doug talks about the importance of being able to extract the useful bits from even a hurtful review: this is important, because it will make the next book better. He talks about the fact that it was hard for him to get up this morning after that review and write, but that he did it anyway. He's in it for the long haul, we can see.

I know some faculty who basically ignore student assessments of their teaching. They paid attention for a while at the beginning of their careers, but it hurt too much, so they stopped. Most of the good teachers I know, though, approach their student assessments the way that Doug approaches his bad review: they look for the truths in the reviews, take those truths seriously, and use them to get better. Yes, a bad set of assessments hurts. But if you are in it for the long haul, you get back to work.

Here, the teacher gives a bad review:

What Doug does for me in this meeting is respect me, by declining to hyperbolize my crap thesis. I don't remember what he said about it, but what he did not say was, you know: "Amazing, you did a great job, this is publishable, you rocked our world with this! Loved the elephant." There's this theory that self-esteem has to do with getting confirmation from the outside world that our perceptions are fundamentally accurate. What Doug does at this meeting is increase my self-esteem by confirming that my perception of the work I'd been doing is fundamentally accurate. The work I've been doing is bad. Or, worse: it's blah. This is uplifting -- liberating, even -- to have my unspoken opinion of my work confirmed. I don't have to pretend bad is good. This frees me to leave it behind and move on and try to do something better. The main thing I feel: respected.

Sometimes, students make their best effort but come up short. They deserve the respect of an honest review. Honest doesn't have to be harsh; there is a difference between being honest and being a jerk. Sometimes, students don't make their best effort, and they deserve the respect of an honest review, too. Again, being honest doesn't mean being harsh. In my experience, most students appreciate an honest, objective review of their work. They almost always know when they are coming up short, or when they aren't working hard enough. When a teacher confirms that knowledge, they are freed -- or motivated in a new way -- to move forward.

Here, the teacher reads student work:

I am teaching at Syracuse myself now. Toby, Arthur Flowers, and I are reading that year's admissions materials. Toby reads every page of every story in every application, even the ones we are almost certainly rejecting, and never fails to find a nice moment, even when it occurs on the last page of the last story of a doomed application. "Remember that beautiful description of a sailboat on around page 29 of the third piece?" he'll say. And Arthur and I will say: "Uh, yeah ... that was ... a really cool sailboat." Toby has a kind of photographic memory re stories, and such a love for the form that goodness, no matter where it's found or what it's surrounded by, seems to excite his enthusiasm. Again, that same lesson: good teaching is grounded in generosity of spirit.

It has taken me a long time as a teacher to learn to have Toby's mindset when reading student work, and I'm still learning. Over the last few years, I've noticed myself trying more deliberately to find the nice moments in students' programs, even the bad ones, and to tell students about them. That doesn't mean being dishonest about the quality of the overall program. But nice moments are worth celebrating, wherever they are found. Sometimes, those are precisely the elements students need to hear about, because they are the building blocks for getting better.

Finally, here is the teacher talking about his own craft:

During the Q&A someone asks what Toby would do if he couldn't be a writer.
A long, perplexed pause.
"I would be very sad", he finally says.

I like teaching computer science, but what has enabled me to stay in the classroom for so many years and given me the stamina to get better at teaching is that I like doing computer science. I like to program. I like to solve problems. I like to find abstractions and look for ways to solve other problems. There are many things I could do if I were not a computer scientist, but knowing what I know now, I would be a little sad.

Posted by Eugene Wallingford | Permalink | Categories: Personal, Teaching and Learning

November 20, 2016 10:17 AM

Celebrating a Friend's Success

Wade Arnold accepting the Young Alumni Award from UNI President Jim Wohlpart

Last week, I read a blog entry by Ben Thompson that said Influence lives at intersections. Thompson was echoing a comment about Daniel Kahneman's career: "Intellectual influence is the ability to dissolve disciplinary boundaries." These were timely references for my week.

On Friday night, I had the pleasure of attending the Heritage Honours Awards, an annual awards dinner hosted by my university's alumni association. One of our alumni, Wade Arnold, received the Young Alumni Award for demonstrated success early in a career. I mentioned Wade in a blog entry several years ago, when he and I spoke together at a seminar on interactive digital technologies. That day, Wade talked about intersections:

It is difficult to be the best at any one thing, but if you are very good at two or three or five, then you can be the best in a particular market niche. The power of the intersection.

Wade built his company, Banno, by becoming very good at several things, including functional programming, computing infrastructure, web development, mobile development, and financial technology. He was foresightful and lucky enough to develop this combination of strengths before most other people did. Most important, though, he worked really hard to build his company: a company that people wanted to work with, and a company that people wanted to work for. As a result, he was able to grow a successful start-up in a small university town in the middle of the country.

It's been a delight for me to know Wade all these years and watch him do his thing. I'll bet he has some interesting ideas in store for the future.

The dinner also provided me with some unexpected feelings. Several times over the course of the evening, someone said, "Dr. Wallingford -- I feel like I know you." I had the pleasure of meeting Wade's parents, who said kind things about my influence on their son. Even his nine-year-old son said, "My dad was talking about you in the car on the drive over." No one was confused about whom we were there to honor Friday night, about who had done the considerable work to build himself into an admirable man and founder. That was all Wade. But my experience that night is a small reminder to all you teachers out there: you do have an effect on people. It was certainly a welcome reminder for me at the end of a trying semester.

Posted by Eugene Wallingford | Permalink | Categories: Personal, Teaching and Learning

October 30, 2016 9:25 AM

Which Part of Speech Am I?

I saw a passage attributed to Søren Kierkegaard that I might translate as:

The life of humanity could very well be conceived as a speech in which different people represented the various parts of speech [...]. How many people are merely adjectives, interjections, conjunctions, adverbs; how few are nouns, verbs; how many are copula?

This is a natural thing to ponder around my birthday. It's not a bad thing to ask myself more often: Which part of speech will I be today?

Posted by Eugene Wallingford | Permalink | Categories: General, Personal

October 26, 2016 3:11 PM

One Way I'm Like Charles Darwin

According to Darwin himself, in his autobiography:

I have no great quickness of apprehension or wit which is so remarkable in some clever men, for instance, Huxley. I am therefore a poor critic: a paper or book, when first read, generally excites my admiration, and it is only after considerable reflection that I perceive the weak points.

If you read my blog, you know this about me. Either you enjoy my occasionally uncritical admiration, or at least you tolerate it.

Posted by Eugene Wallingford | Permalink | Categories: Personal

October 16, 2016 10:34 AM

Missing the Rhythm of Running

I ended up with an unexpected couple of hours free yesterday afternoon, and I decided to clean up several piles of old papers on the floor of my running room. Back when I ran marathons, I was an information hound. I wrote notes, collected maps, and clipped articles on training plans, strength training, stretching and exercise, diet and nutrition -- anything I thought I could use to get get better. I'm sure this surprises many of you.

There was a lot of dust to dig through, but the work was full of happy reminiscences. It's magical how a few pieces of paper can activate our memories. The happy memories leave in their wake a sadness, when my time as a runner ended. That's when the piles stopped growing. I stopped collecting material, because I wasn't running anymore.

Fortunately, the sadness of loss didn't drown out the happy memories. Instead, I started thinking about the future, which is really now. These thoughts are long past due.

Looking back through my running logs reminded of the pattern of my life as a marathoner. There was an ebb and a flow to the year. I trained for my first half marathon. Then I trained for my first full marathon. I ran lightly for a few weeks as my body recovered. Winter and spring saw regular runs, but a break for mind and body alike: no big plans, just enjoying the road. Then came the end of spring, and it started all over again: training for big races. These years were filled with variety in my running, variety in my goals.

The last few years have been different. I recovered from a couple of operations, eventually taking up the elliptical machine and returning to my bike for fitness. However, I have never become a cyclist in spirit the way I became a runner. I've been exercising lots, staying fit and healthy, but I miss the rhythm of running and training for marathons. In comparison, my exercise since leaves me bored and uninspired.

Diving into those piles of paper yesterday started me thinking, what are the next goals? I'll be working on that as we slide into winter, looking forward what next spring might bring.

Posted by Eugene Wallingford | Permalink | Categories: Personal, Running

October 04, 2016 3:40 PM

First, Be Careful What You Teach People To Expect

Last month, Seth Godin posted a short entry about reputation. It brought back memories of my first couple of years as department head. I was excited and wanted to do a good job, so I took on a lot. Pretty soon I was in a position of having promised more than I could deliver. Some of the shortfall resulted from the heavy load itself; there are only so many hours in a week. Some resulted from promising things I couldn't deliver, because I didn't understand the external constraints I faced.

When you don't deliver, explanations sound like excuses.

If I were giving advice to myself at the time I became head (already an adult who should have known better...), I would tell him to heed Godin's advice and help people learn what they can expect from you. Explicit attention to expectations can pay off in seeding reputation but also by setting parameters for yourself. Then live up to that standard.

If you teach people to expect little, perhaps unintentionally, they will -- even on the occasions when you do better. And after you get better, if you do, it takes a long time to undo the expectations you created early on.

Live the life you've taught people to expect from you -- but first be careful what you teach them to expect.

Posted by Eugene Wallingford | Permalink | Categories: Managing and Leading, Personal

September 25, 2016 9:40 AM

There Is Only One Culture, But Two Languages

W.H. Auden, in A Certain World, on the idea of The Two Cultures:

Of course, there is only one. Of course, the natural sciences are just as "humane" as letters. There are, however, two languages, the spoken verbal language of literature, and the written sign language of mathematics, which is the language of science. This puts the scientist at a great advantage, for, since like all of us he has learned to read and write, he can understand a poem or a novel, whereas there are very few men of letters who can understand a scientific paper once they come to the mathematical parts.
When I was a boy, we were taught the literary languages, like Latin and Greek, extremely well, but mathematics atrociously badly. Beginning with the multiplication table, we learned a series of operations by rote which, if remembered correctly, gave the "right" answer, but about any basic principles, like the concept of number, we were told nothing. Typical of the teaching methods then in vogue is the mnemonic which I had to learn.
Minus times Minus equals Plus:
The reason for this we need not discuss.

Sadly, we still teach young people that it's okay if math and science are too hard to master. They grow into adults who feel a chasm between "arts and letters" and "math and science". But as Auden notes rightly, there is no chasm; there is mostly just another language to learn and appreciate.

(It may be some consolation to Auden that we've reached a point where most scientists have to work to understand papers written by scientists in other disciplines. They are written in highly specialized languages.)

In my experience, it is more acceptable for a humanities person to say "I'm not a science person" or "I don't like math" than for a scientist to say something similar about literature, art, or music. The latter person is thought, silently, to be a Philistine; the former, an educated person with a specialty.

I've often wondered if this experience suffers from observation bias or association bias. It may well. I certainly know artists and writers who have mastered both languages and who remain intensely curious about questions that span the supposed chasm between their specialties and mine. I'm interested in those questions, too.

Even with this asymmetry, the presumed chasm between cultures creates low expectations for us scientists. Whenever my friends in the humanities find out that I've read all of Kafka's novels and short stories; that Rosencrantz and Guildenstern Are Dead is my favorite play, or that I even have a favorite play; that I really enjoyed the work of choreographer Merce Cunningham; that my office bookshelf includes the complete works of William Shakespeare and a volume of William Blake's poetry -- I love the romantics! -- most seem genuinely surprised. "You're a computer scientist, right?" (Yes, I like Asimov, Heinlein, Clarke, and Bradbury, too.)

Auden attributes his illiteracy in the language of mathematics and science to bad education. The good news is that we can reduce, if not eliminate, the language gap by teaching both languages well. This is a challenge for both parents and schools and will take time. Change is hard, especially when it involves the ways we talk about the world.

Posted by Eugene Wallingford | Permalink | Categories: General, Personal, Teaching and Learning

September 18, 2016 3:49 PM

Talking Shop

a photo of the Blueridge Orchard, visited by cyclists on the Cedar Valley Farm Ride

I agree with W.H. Auden:

Who on earth invented the silly convention that it is boring or impolite to talk shop? Nothing is more interesting to listen to, especially if the shop is not one's own.

My wife went on a forty-mile bike ride this morning, a fundraiser for the Cedar Valley Bicycle Collective, which visited three local farms. At those stops, I had the great fortune to listen to folks on all three farms talk shop. We learned about making ice cream and woodcarving at Three Pines Farm. We learned about selecting, growing, and picking apples -- and the damage hail and bugs can do -- at Blueridge Orchard. And the owner of the Fitkin Popcorn Farm talked about the popcorn business. He showed us the machines they use to sort the corn out of the field, first by size and then by density. He also talked about planting fields, harvesting the corn, and selling the product nationally. I even learned that we can pop the corn while it's still on the ears! (This will happen in my house very soon.)

I love to listen to people talk shop. In unguarded moments, they speak honestly about something they love and know deeply. They let us in on what it is like for them to work in their corner of the world. However big I try to make my world, there is so much more out there to learn.

The Auden passage is from his book A Certain World, a collage of poems, quotes, and short pieces from other writers with occasional comments of his own. Auden would have been an eclectic blogger! This book feels like a Tumblr blog, without all the pictures and 'likes'. Some of the passages are out of date, but they let us peak in on the mind of an accomplished poet. A little like good shop talk.

Posted by Eugene Wallingford | Permalink | Categories: General, Personal, Teaching and Learning

September 16, 2016 12:41 PM

We Are All Mashups

Sheldon reminds Leonard that he never really had a personality, on The Bib Bang Theory

There is a scene in The Big Bang Theory where Sheldon laments that, without realizing it, he had allowed his girl/friend to alter his personality. Leonard responds, "Well, you didn't really have a 'personality'. You just had some shows you liked."

This scene came to mind when I read a passage from Kenneth Goldsmith's Uncreative Writing earlier this week:

I don't think there's a stable or essential "me". I am an amalgamation of many things: books I've read, movies I've seen, television shows I've watched, conversations I've had, songs I've sung, lovers I've loved. In fact, I'm a creation of so many people and so many ideas, to the point where I feel I've actually had few original thoughts and ideas; to think that what I consider to be "mine" was "original" would be blindingly egotistical.

It is occasionally daunting when I realize how much I am a product of the works, people, and ideas I've encountered. How can I add anything new? But when I surrender to the fact that I can't, it frees me to write and do things that I like. What I make may not be new, but it can still be useful or valuable, even if only to me.

I wonder what it's like for kids to grow up in a self-consciously mash-up culture. My daughters have grown up in a world where technology and communication have given everyone the ability to mix and modify other work so easily. It's a big part of the entertainment they consume.

Mash-up culture must feel hugely empowering in some moments and hugely terrifying in others. How can anyone find his or her own voice, or say something that matters? Maybe they have a better sense than I did growing up that nothing is really new and that what really matters is chasing your interests, exploring the new lands you enter, and sharing what you find. That's certainly been the source of my biggest accomplishments and deepest satisfactions.

(I ran across the passage from Goldsmith on Austin Kleon's blog.)

Posted by Eugene Wallingford | Permalink | Categories: General, Personal

September 10, 2016 10:41 AM

Messages Rather Than Conversations

Kevin Kelly, in Amish Hackers:

One Amish-man told me that the problem with phones, pagers, and PDAs (yes he knew about them) was that "you got messages rather than conversations". That's about as an accurate summation of our times as any. Henry, his long white beard contrasting with his young bright eyes told me, "If I had a TV, I'd watch it." What could be simpler?

Unlike some younger Amish, I still do not carry a smart phone. I do own a cell but use it only when traveling. If our home phone disappeared overnight, it would likely take several days before my wife or I even noticed.

I also own a television, a now-déclassé 32" flat screen. Henry is right: having a TV, I find myself watching it on occasion. I enjoy it but have to guard vigilantly against falling into a hypnotic trance. It turns out that I form certain habits quite easily.

Posted by Eugene Wallingford | Permalink | Categories: General, Personal

August 07, 2016 10:36 AM

Some Advice for How To Think, and Some Personal Memories

I've been reading a bunch of the essays on David Chapman's Meaningness website lately, after seeing a link to one on Twitter. (Thanks, @kaledic.) This morning I read How To Think Real Good, about one of Chapman's abandoned projects: a book of advice for how to think and solve problems. He may never write this book as he once imagined it, but I'm glad he wrote this essay about the idea.

First of all, it was a fun read, at least for me. Chapman is a former AI researcher, and some of the stories he tells remind me of things I experienced when I was in AI. We were even in school at about the same time, though in different parts of the country and different kinds of program. His work was much more important than mine, but I think at some fundamental level most people in AI share common dreams and goals. It was fun to listen as Chapman reminisced about knowledge and AI.

He also introduced me to the dandy portmanteau anvilicious. I keep learning new words! There are so many good ones, and people make up the ones that don't exist already.

My enjoyment was heightened by the fact that the essay stimulated the parts of my brain that like to think about thinking. Chapman includes a few of the heuristics that he intended to include in his book, along with anecdotes that illustrate or motivate them. Here are three:

All problem formulations are "false", because they abstract away details of reality.
Solve a simplified version of the problem first. If you can't do even that, you're in trouble.
Probability theory is sometimes an excellent way of dealing with uncertainty, but it's not the only way, and sometimes it's a terrible way.

He elaborates on the last of these, pointing out that probability theory tends to collapse many different kinds of uncertainty into a single value. This does not work all that well in practice, because different kinds of uncertainty often need to be handles in very different ways.

Chapman has a lot to say about probability. This essay was prompted by what he sees as an over-reliance of the rationalist community on a pop version of Bayesianism as its foundation for reasoning. But as an old AI researcher, he knows that an idea can sound good and fail in practice for all sorts of reasons. He has also seen how a computer program can make clear exactly what does and doesn't work.

Artificial intelligence has always played a useful role as a reality check on ideas about mind, knowledge, reasoning, and thought. More generally, anyone who writes computer programs knows this, too. You can make ambiguous claims with English sentences, but to write a program you really have to have a precise idea. When you don't have a precise idea, your program itself is a precise formulation of something. Figuring out what that is can be a way of figuring out what you were really thing about in the first place.

This is one of the most important lessons college students learn from their intro CS courses. It's an experience that can benefit all students, not just CS majors.

Chapman also includes a few heuristics for approaching the problem of thinking, basically ways to put yourself in a position to become a better thinker. Two of my favorites are:

Try to figure out how people smarter than you think.
Find a teacher who is willing to go meta and explain how a field works, instead of lecturing you on its subject matter.

This really is good advice. Subject matter is much easier to come by than deep understanding of how the discipline work, especially in these days of the web.

The word meta appears frequently throughout this essay. (I love that the essay is posted on the metablog/ portion of his site!) Chapman's project is thinking about thinking, a step up the ladder of abstraction from "simply" thinking. An AI program must reason; an AI researcher must reason about how to reason.

This is the great siren of artificial intelligence, the source of its power and also its weaknesses: Anything you can do, I can do meta.

I think this gets at why I enjoyed this essay so much. AI is ultimately the discipline of applied epistemology, and most of us who are lured into AI's arms share an interest in what it means to speak of knowledge. If we really understand knowledge, then we ought to be able to write a computer program that implements that understanding. And if we do, how can we say that our computer program isn't doing essentially the same thing that makes us humans intelligent?

As much as I love computer science and programming, my favorite course in graduate school was an epistemology course I took with Prof. Rich Hall. It drove straight to the core curiosity that impelled me to study AI in the first place. In the first week of the course, Prof. Hall laid out the notion of justified true belief, and from there I was hooked.

A lot of AI starts with a naive feeling of this sort, whether explicitly stated or not. Doing AI research brings that feeling into contact with reality. Then things gets serious. It's all enormously stimulating.

Ultimately Chapman left the field, disillusioned by what he saw as a fundamental limitation that AI's bag of tricks could never resolve. Even so, the questions that led him to AI still motivate him and his current work, which is good for all of us, I think.

This essay brought back a lot of pleasant memories for me. Even though I, too, am no longer in AI, the questions that led me to the field still motivate me and my interests in program design, programming languages, software development, and CS education. It is hard to escape the questions of what it means to think and how we can do it better. These remain central problems of what it means to be human.

Posted by Eugene Wallingford | Permalink | Categories: Computing, Personal, Teaching and Learning

August 04, 2016 11:51 AM

The Spirit Of Our Time: Sensation Brought To An Extreme

Jack Levine, on painting as a realist in the 1950s, a time of abstract expressionism and art as social commentary:

The difficulty is for me to be affirmative. I'm a little inhibited, as you have noticed, by not being against any of these people. The spirit of denunciation is more in the spirit of our time: sensation brought to an extreme.

Levine might just as well have been talking about today's social and political climate. Especially if he had had a Facebook or Twitter account.


(This passage comes from Conversations with Artists. These entries also draw passages from it: [ 07/19 | 07/27 | 07/31 ]. This is my last entry drawn from the book, at least for now.)

Posted by Eugene Wallingford | Permalink | Categories: General, Personal

July 22, 2016 11:02 AM

What Happens When We Read To Kids

A great analogy from Frank Cottrell:

Think of it, he says, the sun pours down its energy onto the surface of the planet for millennia. The leaves soak up the energy. The trees fall and turn to coal. Coal is solid sunlight, the stored memory of millions of uninhabited summers. Then one day, in Coalbrookdale, someone opens a hole in the ground and all that stored energy comes pouring out and is consumed in furnaces, engines, motors.

When we -- teachers, parents, carers, friends -- read to our children, I believe that's what we're doing. Laying down strata of fuel, fuel studded with fossils and treasures. If we ask for anything back, we burn it off too soon.

My wife and I surely did a lot of things wrong as we raised our daughters, but I think we did at least two things right: we read to them all the time, and we talked to them like we talk to everyone else. Their ability to speak and reason and imagine grew out of those simple, respectful acts.

Teaching at a university creates an upside-down dynamic by comparison, especially in a discipline many think of as being about jobs. It is the students and parents who are more likely to focus on the utility of knowledge. Students sometimes ask, "When will we use this in industry?" With the cost of tuition and the uncertainty of the times, I understand their concern. Even so, there are times I would like to say "I don't know" or, in my weaker moments, the seemingly disrespectful "I don't care". Something more important should be happening here. We are creating fuel for a lifetime.

(The Cottrell article takes an unusual route to an interesting idea. It was worth a read.)

Posted by Eugene Wallingford | Permalink | Categories: Personal, Teaching and Learning

June 08, 2016 2:48 PM

Happy Birthday Programming

Yesterday, I wrote me some Java. It was fun.

A few days ago, I started wondering if there was something unique I could send my younger daughter for her birthday today. My daughters and I were all born in presidential election years, which is neat little coincidence. This year's election is special for the birthday girl: it is her first opportunity to vote for the president. She has participated in the process throughout, which has seen both America's most vibrant campaign for progressive candidate in at least forty years and the first nomination of a woman by a major party. Both of these are important to her.

In the spirit of programming and presidential politics, I decided to write a computer program to convert images into the style of Shepard Fairey's iconic Obama "Hope" poster and then use it to create a few images for her.

I dusted off Dr. Java and fired up some code I wrote when I taught media computation in our intro course many years ago. It had been a long time since I had written any Java at all, but it came back just like riding a bike. More than decade of writing code in a language burns some pretty deep grooves in the mind.

I found RGB values to simulate the four colors in Fairey's poster in an old message to the mediacomp mailing list:

    Color darkBlue  = new Color(0, 51, 76);
    Color lightBlue = new Color(112, 150, 158);
    Color red       = new Color(217, 26, 33);
    Color yellow    = new Color(252, 227, 166);

Then came some experimentation...

  • First, I tried turning each pixel into the Fairey color to which it was closest. That gave an image that was grainy and full of lines, almost like a negative.

  • Then I calculated the saturation of each pixel (the average of its RGB values) and translated the pixel into one of the four colors depending on which quartile it was in. If the saturation was less than 256/4, it went dark blue; if it was less than 256/2, it went red; and so on. This gave a better result, but some images ended up having way too much of one or two of the colors.

  • Attempt #2 skews the outputs because in many images (most?) the saturation values are not distributed evenly over the four quartiles. So I wrote a function to "normalize" the quartiles. I recorded all of the saturation values in the image and divided them evenly across the four colors. The result was an image with an equal numbers of pixels assigned to each of the four colors.

I liked the outputs of this third effort quite a bit, at least for the photos I gave it as input. Two of them worked out especially well. With a little doctoring in Photoshop, they would have an even more coherent feel to them, like an artist might produce with a keener eye. Pretty good results for a few fun minutes of programming.

Now, let's hope my daughter likes them. I don't think she's ever received a computer-generated present before, at least not generated by a program her dad wrote!

The images I created were gifts to her, so I'll not share them here. But if you've read this far, you deserve a little something, so I give you these:

Eugene obamified by his own program, version 1
Eugene obamified by his own program, version 2

Now that is change we can all believe in.

Posted by Eugene Wallingford | Permalink | Categories: Computing, Personal

May 27, 2016 1:38 PM

Brilliance Is Better Than Magic, Because You Get To Learn It

Brent Simmons has recently suggested that Swift would be better if it were more dynamic. Some readers have interpreted his comments as an unwillingness to learn new things. In Oldie Complains About the Old Old Ways, Simmons explains that new things don't bother him; he simply hopes that we don't lose access to what we learned in the previous generation of improvements. The entry is short and worth reading in its entirety, but the last sentence of this particular paragraph deserves to be etched in stone:

It seemed like magic, then. I later came to understand how it worked, and then it just seemed like brilliance. (Brilliance is better than magic, because you get to learn it.)

This gets to close to the heart of why I love being a computer scientist.

So many of the computer programs I use every day seem like magic. This might seem odd coming from a computer scientist, who has learned how to program and who knows many of the principles that make complex software possible. Yet that complexity takes many forms, and even a familiar program can seem like magic when I'm not thinking about the details under its hood.

As a computer scientist, I get to study the techniques that make these programs work. Sometimes, I even get to look inside the new program I am using, to see the algorithms and data structures that bring to life the experience that feels like magic.

Looking under the hood reminds me that it's not really magic. It isn't always brilliance either, though. Sometimes, it's a very cool idea I've never seen or thought about before. Other times, it's merely a bunch of regular ideas, competently executed, woven together in a way that give an illusion of magic. Regular ideas, competently executed, have their own kind of beauty.

After I study a program, I know the ideas and techniques that make it work. I can use them to make my own programs.

This fall, I will again teach a course in compiler construction. I will tell a group of juniors and seniors, in complete honesty, that every time I compile and execute a program, the compiler feels like magic to me. But I know it's not. By the end of the semester, they will know what I mean; it won't feel like magic to them any more, either. They will have learned how their compilers work. And that is even better than the magic, which will never go away completely.

After the course, they will be able to use the ideas and techniques they learn to write their own programs. Those programs will probably feel like magic to the people who use them, too.

Posted by Eugene Wallingford | Permalink | Categories: Computing, Personal, Software Development

May 07, 2016 10:55 AM

Without Wonder, Without Awe

Henry Miller, in "The Books in My Life" (1969):

Every day of his life the common man makes use of what men in other ages would have deemed miraculous means. In the range of invention, if not in powers of invention, the man of today is nearer to being a god than at any time in history. (So we like to believe!) Yet never was he less godlike. He accepts and utilizes the miraculous gifts of science unquestioningly; he is without wonder, without awe, reverence, zest, vitality, or joy. He draws no conclusions from the past, has no peace or satisfaction in the present, and is utterly unconcerned about the future. He is marking time.

It's curious to me that this was written around the same time as Stewart Brand's clarion call that we are as gods. The zeitgeist of the 1960s, perhaps.

"The Books in My Life" really has been an unexpected gift. As I noted back in November, I picked it up on a lark after reading a Paris Review interview with Miller, and have been reading it off and on since. Even though he writes mostly of books and authors I know little about, his personal reflections and writing style click with me. Occasionally, I pick up one of the books he discusses, ost recently Richard Jefferies's The Story of My Heart.

When other parts of the world seem out of sync, picking up the right book can change everything.

Posted by Eugene Wallingford | Permalink | Categories: General, Personal

May 02, 2016 4:30 PM

A Pawn and a Move

So, a commodity chess program is now giving odds of a pawn and a move to a world top-ten player -- and winning?

The state of computer chess certainly has changed since the fall of 1979, when I borrowed Mike Jeffers's Chess Challenger 7 and played it over and over and over. I was a rank novice, really just getting my start as a player, yet after a week or so I was able to celebrate my first win over the machine, at level 3. You know what they say about practice...

My mom stopped by our study room several times during that week, trying to get me to stop playing. It turns out that she and my dad had bought me a Chess Challenger 7 for Christmas, and she didn't want me to tire of my present before I had even unwrapped it. She didn't know just how not tired I would get of that computer. I wore it out.

When I graduated with my Ph.D., my parents bought me Chess Champion 2150L, branded by in the name of world champion Garry Kasparov. The 2150 in the computer's name was a rough indication that it played expert-level chess, much better than my CC7 and much better than me. I could beat it occasionally in a slow game, but in speed chess it pounded me mercilessly. I no longer had the time or inclination to play all night, every night, in an effort to get better, so it forever remained my master.

Now US champ Hikaru Nakamura and world champ Magnus Carlsen know how I feel. The days of any human defeating even the programs you can buy at Radio Shack have long passed.

Two pawns and move odds against grandmasters, and a pawn and a move odds against the best players in the world? Times have changed.

Posted by Eugene Wallingford | Permalink | Categories: Computing, Personal

April 29, 2016 3:30 PM

A Personal Pantheon of Programming Books

Michael Fogus, in the latest issue of Read-Eval-Print-λove, writes:

The book in question was Thinking Forth by Leo Brodie (Brodie 1987) and upon reading it I immediately put it into my own "personal pantheon" of influential programming books (along with SICP, AMOP, Object-Oriented Software Construction, Smalltalk Best Practice Patterns, and Programmers Guide to the 1802).

Mr. Fogus has good taste. Programmers Guide to the 1802 is new to me. I guess I need to read it.

The other five books, though, are in my own pantheon influential programming books. Some readers may be unfamiliar with these books or the acronyms, or aware that so many of them are available free online. Here are a few links and details:

  • Thinking Forth teaches us how to program in Forth, a concatenative language in which programs run against a global stack. As Fogus writes, though, Brodie teaches us so much more. He teaches a way to think about programs.

  • SICP is Structure and Interpretation of Computer Programs, hailed by many as the greatest book on computer programming ever written. I am sympathetic to this claim.

  • AMOP is The Art of the Metaobject Protocol, a gem of a book that far too few programmers know about. It presents a very different and more general kind of OOP than most people learn, the kind possible in a language like Common Lisp. I don't know of an authorized online version of this book, but there is an HTML copy available.

  • Object-Oriented Software Construction is Bertrand Meyer's opus on OOP. It did not affect me as deeply as the other books on this list, but it presents the most complete, internally consistent software engineering philosophy of OOP that I know of. Again, there seems to be an unauthorized version online.

  • I love Smalltalk Best Practice Patterns and have mentioned it a couple of times over the years [ 1 | 2 ]. Ounce for ounce, it contains more practical wisdom for programming in the trenches than any book I've read. Don't let "Smalltalk" in the title fool you; this book will help you become a better programmer in almost any language and any style. I have a PDF of a pre-production draft of SBPP, and Stephane Ducasse has posted a free online copy, with Kent's blessing.
Paradigms of Artificial Intelligence Programming

There is one book on my own list that Fogus did not mention: Paradigms of Artificial Intelligence Programming, by Peter Norvig. It holds perhaps the top position in my personal pantheon. Subtitled "Case Studies in Common Lisp", this book teaches Common Lisp, AI programming, software engineering, and a host of other topics in a classical case studies fashion. When you finish working through this book, you are not only a better programmer; you also have working versions of a dozen classic AI programs and a couple of language interpreters.

Reading Fogus's paragraph of λove for Thinking Forth brought to mind how I felt when I discovered PAIP as a young assistant professor. I once wrote a short blog entry praising it. May these paragraphs stand as a greater testimony of my affection.

I've learned a lot from other books over the years, both books that would fit well on this list (in particular, A Programming Language by Kenneth Iverson) and others that belong on a different list (say, Gödel, Escher, Bach -- an almost incomparable book). But I treasure certain programming books in a very personal way.

Posted by Eugene Wallingford | Permalink | Categories: Computing, Personal, Software Development, Teaching and Learning

April 24, 2016 6:46 PM

A Short Break in Boston

This weekend has been a normal one at home, a little online and a little off, but last weekend I went offline for most of three and a half days to visit my older daughter in Boston. She been in Jamaica Plain in for eight months and had plenty of sights to show. I hadn't spent much time in Boston since AAAI 1990 and, except for the walk across the Charles River from my MIT dorm room, had forgotten most of the details of that trip. Now that I blog, I can preserve my memories for 2042 me.

Offline.   Being offline for most of three and a half days was a treat. I had my laptop on for only a couple of hours in the Chicago airport when I used a long layover to grade one of my students programming assignments. Thereafter, I left it in its bag, turned off. It was great to be present to my daughter and the world for a while without feeling the need to check mail or tinker with work.

Goal.   At the airport, I saw several members of the Fort Lauderdale Strikers, a North American Soccer League team. I'm guessing they were passing through ORD en route to a match with the Minnesota United. From the score of the game, I think my weekend went better than theirs.

Confluence.   Saturday morning, we went out for brunch at the Center Street Cafe in Jamaica Plain. We arrived a few minutes after opening. Seating is limited, so we waited outside in line.

There was one party ahead of us, a young couple. The young woman kept looking at my jacket and finally said, "Did you go to UNI?" When I told her that I teach there and that my daughter is from Cedar Falls, she told us that she is from Des Moines. The older guy behind me in line heard us discussing Iowa, asked where we were from, said that he is from Council Bluffs, and recalled that a good friend of his UNI. We all marveled at the coincidence. Our new Council Bluffs friend wondered what it was that attracted Iowans to Boston; I silently wondered if Boston depended on an influx of Iowa talent to stay fresh.

The food was excellent, too.

Walking.   After brunch, my daughter and I spent several hours walking in the Arnold Arboretum and the Forest Hills Cemetery. The arboretum is not yet in bloom yet still had plenty of neat things to see, as well as a prodigious hill to climb. The cemetery is full of impressive monuments and interesting sculpture.

For some reason, I got it in my head that I wanted that I wanted to see e.e. cummings's cemetery marker. I did not know that it is famously difficult to find. Alas, after several hours on foot at the arboretum and cemetery in the sun, my brain was not up to the task of finding it. Now I have extra motivation to return to JP. I'll have a picture next time.

The Arts.   We decided to spend Sunday afternoon at the Museum of Fine Arts, but I could have spent a week there. Our first stop was the special exhibit called Megacities, by artists from cities that have, in the last few decades, grown to populations in excess of 20 million people. These artists are responding to what this growth means for the people, their way of life, and the cities themselves. The old architecture student in me was drawn especially to two spaces created to evoke the cities that existed before the growth:

  • Hu Xiangcheng's room-like installation made from windows and doors that were salvaged from Ming- and Qing-era houses torn down to make way for modern buildings
  • Asim Waqif's bamboo scaffolding inspired by the changes in construction techniques in Delhi

Sarah wanted to be sure to see a painting she likes, of a big storm in a valley, and otherwise was open to explore. It turned out to be Albert Bierstadt's wonderful Storm in the Mountains. I expressed interest in the impressionists, so we made sure to swing through those galleries, too. The Pisarros took more of my attention than in the past, and the Monets lived up to my expectations. We spent several minutes examining several of his Rouen Cathedral canvases and several of his Morning on the Seine works up close, then walked to the opposite corner of the room to experience them from a distance. It was hard to leave.

A New Favorite.   The MFA has an extensive collection of John Singer Sargent's work, about which I had much to learn. I left the weekend with a new painting among my favorites, Sargent's "An Artist in His Studio":

An Artist in His Studio, by John Singer Sargent, 1904

Up close, the detail in the bedding grabs the eye: "Surely, never were tumbled white sheets so painted before." The artist at work.

Coincidence.   My reading for the trip was The Book of Tea, Okakura Kakuzo's short book on the Japanese tea ceremony and its intimate connection to art, culture, and philosophy. Until I reached the biographical essay at the back of this 1956 edition of the book, I did not know that Okakura had a connection to the MFA in Boston:

The wholesale destruction of a nation's cultural heritage [in the late 19th century] aroused to action a small group of Japanese artists and men of letters and a handful of foreigners who seemed more concerned about the fate of Japanese art than were many native hotheads. The nucleus of this movement emerged from the Imperial University in Tokyo, with Professors Morse and Fenollosa in the lead, and with Kano Hogai, of the ancient family of artists, to act as historic instructor. Fenollosa urged his wealthy friend, William Sturgis Bigelow, to buy up whatever of value was tossed on a careless market; this was to become the core of the great Oriental collection of the Boston Museum. Okakura Kakuzo and Baron Kuki were the most energetic Japanese workers in this group.

Iowans and Japanese intersecting with Boston. The Oriental collection is definitely on the itinerary for my next visit.

Much More.   We packed the weekend from morning until night, beginning with a workout at my daughter's gym and ending each night with a film. In addition to the places I've mentioned, we visited the aquarium, the North End, Boston Common, and the public garden, another brunch at Vee Vee, and a dinner at Bella Luna. It was a weekend well-spent.

A Modern Man.   I even joined the 21st century on this trip. I sent a text for no purpose other than to say 'hello'. My daughter and I streamed movies from Netflix. And I relied on my cell phone alarm to awaken to catch a cab at 5:00 AM. A weekend well-spent, indeed.

PLT Rising.   One last bit of new knowledge: Northeastern University is but two short subway stops from where I got off for my visit. This means that my next visit to Jamaica Plain, should there be one, will include a visit to see the home of the PLT group there. If nothing else, I can take snapshots of the labs and offices where so much cool Racket work is done. Then maybe I could write the excursion off as a business trip.

Posted by Eugene Wallingford | Permalink | Categories: Personal

April 07, 2016 3:47 PM

Notes from Today's Reading

Getting Older

In Fun With Aging, "Dean Dad" Matt Reed pontificates on reaching a Certain Age.

When Mom was the age I am now, I was in grad school. That can't possibly be right, but that's what the math says.

When my mom was the age I am now, I was already in my second year as an assistant professor, a husband, and father to a two-year-old daughter. Wow.

Getting old: what a strange thing to happen to a little boy.

That said, I am one up on Reed: I know one of Justin Bieber's recent songs and quite like it.

An Interesting Juxtaposition

Earlier this week, I read The Real Reason Middle America Should Be Angry, about St. Louis's fall from national prominence. This morning, I read The Refragmentation, Paul Graham's essay on the dissolution of the 20th century's corporate and cultural order abetted, perhaps accelerated, by computation.

Both tell a story of the rise and fall of corporations across the 20th century. Their conclusions diverge widely, though, especially on the value of government policies that affect scale. I suspect there are elements of truth in both arguments. In any case, they make interesting bookends to the week.

A Network of Links

Finally, as I tweeted yesterday, a colleague told me that he was going to search my blog. He had managed to forget where his own blog lives, and he remembered that I linked to it once.

At first, I chuckled at this situation as a comment on his forgetfulness, and ruefully as a comment on the passing of the age of the blog. But later I realized that this is as much a comment on the wonderfulness of blogging culture, in which links are life and, as long as the network is alive, conversation can be revived.

I hope he blogs again.

Posted by Eugene Wallingford | Permalink | Categories: General, Personal

March 30, 2016 3:21 PM

Quick Hits at the University

This morning I read three pieces with some connection to universities and learning. Each had a one passage that made me smart off silently as I pedaled.

From The Humanities: What's The Big Idea?:

Boyarin describes his own research as not merely interdisciplinary but "deeply post-disciplinary." (He jokes that when he first came to Berkeley, his dream was to be 5 percent in 20 departments.)

Good luck getting tenure that way, dude.

"Deeply post-disciplinary" is a great bit of new academic jargon. Universities are very much organized by discipline. Figuring out how to support scholars who work outside the lines is a perpetual challenge, one that we really should address at scale if we want to enable universities to evolve.

From this article on Bernie Sanders's free college plan:

Big-picture principles are important, but implementation is important, too.

Hey, maybe he just needs a programmer.

Implementing big abstractions is hard enough when the substance is technical. When you throw in social systems and politics, implementing any idea that deviates very far from standard practice becomes almost impossible. Big Ball of Mud, indeed.

From Yours, Isaac Asimov: A Life in Letters:

Being taught is the intellectual analog of being loved.

I'll remind my students of this tomorrow when I give them Exam 3, on syntactic abstraction. "I just called to say 'I love you'."

Asimov is right. When I think back on all my years in school, I feel great affection for so many of my teachers, and I recall feeling their affection for me. Knowledge is not only power, says Asimov; it is happiness. When people help me learn they offer me knew ways to be happy.

( The Foundation Trilogy makes me happy, too.)

Posted by Eugene Wallingford | Permalink | Categories: General, Personal, Teaching and Learning

March 14, 2016 5:27 PM

Can AlphaGo Teach Us to Play Go Better?

All Systems Go -- the cover of Nature magazine
Nature heralds AlphaGo's arrival
courtesy of the American Go Association

In Why AlphaGo Matters, Ben Kamphaus writes:

AlphaGo recognises strong board positions by first recognizing visual features in the board. It's connecting movements to shapes it detects. Now, we can't see inside AlphaGo unless DeepMind decides they want to share some of the visualizations of its intermediate representations. I hope they do, as I bet they'd offer a lot of insight into both the game of Go and how AlphaGo specifically is reasoning about it.

I'm not sure seeing visualizations of AlphaGo's intermediate representations would offer much insight into either the game of Go or how AlphaGo reasons about it, but I would love to find out.

One of the things that drew me to AI when I was in high school and college was the idea that computer programs might be able to help us understand the world better. At the most prosaic level, I though this might happen in what we had to learn in order to write an intelligent program, and in how we structured the code that we wrote. At a more interesting level, I thought that we might have a new kind of intelligence with which to interact, and this interaction would help us to learn more about the domain of the program's expertise.

Alas, computer chess advanced mostly by making computers that were even faster at applying the sort of knowledge we already have. In other domains, neural networks and then statistical approaches led to machines capable of competent or expert performance, but their advances were opaque. The programs might shed light on how to engineer systems, but the systems themselves didn't have much to say to us about their domains of expertise or competence.

Intelligent programs, but no conversation. Even when we play thousands of games against a chess computer, the opponent seems otherworldly, with no new principles emerging. Perhaps new principles are there, but we cannot see them. Unfortunately, chess computers cannot explain their reasoning to us; they cannot teach us. The result is much less interesting to me than my original dreams for AI.

Perhaps we are reaching a point now where programs such as AlphaGo can display the sort of holistic, integrated intelligence that enables them to teach us something about the game -- even if only by playing games with us. If it turns out that neural nets, which are essentially black boxes to us, are the only way to achieve AI that can work with us at a cognitive level, I will be chagrined. And most pleasantly surprised.

Posted by Eugene Wallingford | Permalink | Categories: Computing, Personal

January 29, 2016 3:43 PM

Marvin Minsky and the Irony of AlphaGo

Semantic Information Processing on my bookshelf
a portion of my bookshelf
(CC BY 3.0 US)

Marvin Minsky, one of the founders of AI, died this week. His book Semantic Information Processing made a big impression on me when I read it in grad school, and his paper Why Programming is a Good Medium for Expressing Poorly Understood and Sloppily-Formulated Ideas remains one of my favorite classic AI essays. The list of his students contains many of the great names from decades of computer science; several of them -- Daniel Bobrow, Bertram Raphael, Eugene Charniak, Patrick Henry Winston, Gerald Jay Sussman, Benjamin Kuipers, and Luc Steels -- influenced my work. Winston wrote one of my favorite AI textbooks ever, one that captured the spirit of Minsky's interest in cognitive AI.

It seems fitting that Minsky left us the same week that Google published the paper Mastering the Game of Go with Deep Neural Networks and Tree Search, which describes the work that led to AlphaGo, a program strong enough to beat an expert human Go player. ( This brief article describes the accomplishment and program at a higher level.) One of the key techniques at the heart of AlphaGo is neural networks, an area Minsky pioneered in his mid-1950s doctoral dissertation and continued to work in throughout his career.

In 1969, he and Seymour Papert published a book, Perceptrons, which showed the limitations of a very simple kind of neural network. Stories about the book's claims were quickly exaggerated as they spread to people who had never read the book, and the resulting pessimism stifled neural network research for more than a decade. It is a great irony that, in the week he died, one of the most startling applications of neural networks to AI was announced.

Researchers like Minsky amazed me when I was young, and I am more amazed by them and their lifelong accomplishments as I grow older. If you'd like to learn more, check out Stephen Wolfram's personal farewell to Minsky. It gives you a peek into the wide-ranging mind that made Minsky such a force in AI for so long.

Posted by Eugene Wallingford | Permalink | Categories: Computing, Personal

December 12, 2015 3:04 PM

Agreement: The Rare and Beautiful Exception

From How to Disagree:

Once disagreement starts to be seen as utterly normal, and agreement the rare and beautiful exception, we can stop being so surprised and therefore so passionately annoyed when we meet with someone who doesn't see eye-to-eye with us.

Sometimes, this attitude comes naturally to me. Other times, though, I have to work hard to make it my default stance. Things usually go better for me when I succeed.

Posted by Eugene Wallingford | Permalink | Categories: General, Personal

December 01, 2015 4:38 PM

A Non-Linear Truth about Wealth and Happiness

This tweet has been making the rounds again the last few days. It pokes good fun at the modern propensity to overuse the phrase 'exponential growth', especially in situations that aren't exponential at all. This usage has even invaded the everyday speech of many of my scientist friends, and I'm probably guilty more than I'd like to admit.

In The Day I Became a Millionaire, David Heinemeier Hansson avoids this error when commenting on something he's learned about wealth and happiness:

The best things in life are free. The second best things are very, very expensive. -- Coco Chanel
While the quote above rings true, I'd add that the difference between the best things and the second best things is far, far greater than the difference between the second best things and the twentieth best things. It's not a linear scale.

I started to title this post "A Power Law of Wealth and Happiness" before realizing that I was falling into a similar trap common among computer scientists and software developers these days: calling every function with a steep end and a long tail "a power law". DHH does not claim that the relationship between cost and value is exponential, let alone that it follows a power law. I reined in my hyperbole just in time. "A Non-Linear Truth ..." may not have quite the same weight of power law academic-speak, but it sounds just fine.

By the way, I agree with DHH's sentiment. I'm not a millionaire, but most of the things that contribute to my happiness would scarcely be improved by another zero or two in my bank account. A little luck at birth afforded me almost all of what I need in life, as it has many other people. The rest is an expectations game that is hard to win by accumulating more.

Posted by Eugene Wallingford | Permalink | Categories: Computing, Personal

November 26, 2015 11:04 AM

I Am Thankful for Programming

I smiled a big smile when I read this passage in an interview with Victoria Gould, a British actor and mathematician:

And just as it did when she was at school, maths still brings Victoria relief and reassurance. "When teaching or acting becomes stressful, I retreat to maths a lot for its calmness and its patterns. I'll quite often, in a stressful time, go off and do a bit of linear algebra or some trigonometric identities. They're hugely calming for me." Maths as stress relief? "Absolutely, it works every time!"

It reminded me of a former colleague, a mathematician who now works at Ohio University. He used to say that he had pads and pencils scattered on tables and counters throughout his house, because "I never know when I'll get the urge to do some math."

Last night, I came home after a couple of days of catching up on department work and grading. Finally, it was time to relax for the holiday. What did I do first? I wrote a fun little program in Python to reverse an integer, using only arithmetic operators. Then I watched a movie with my wife. Both relaxed me.

I was fortunate as a child to find solace in fiddling with numbers and patterns. Setting up a system of equations and solving it algebraically was fun. I could while away many minutes playing with the square root key on my calculator, trying to see how long it would take me to drive a number to 1.

Then in high school I discovered programming, my ultimate retreat.

On this day, I am thankful for many people and many things, of course. But Gould's comments remind me that I am also thankful for the privilege of knowing how to program, and for the way it allows me to escape into a world away from stress and distraction. This is a gift.

Posted by Eugene Wallingford | Permalink | Categories: Computing, Personal

November 08, 2015 9:37 AM

Enthusiastic Recommendation Is Not A Vice

Novelist Henry Miller lamented one of his greatest vices, recommending books and authors too enthusiastically, but ultimately decided that he would not apologize for it:

However, this vice of mine, as I see it, is a harmless one compared with those of political fanatics, military humbugs, vice crusaders, and other detestable types. In broadcasting to the world my admiration and affection, my gratitude and reverence, ... I fail to see that I am doing any serious harm. I may be guilty of indiscretion, I may be regarded as a naïve dolt, I may be criticized justly or unjustly for my taste, or lack of it; I may be guilty, in the high sense, of "tampering" with the destiny of others; I may be writing myself down as one more "propagandist", but -- how am I injuring anyone? I am no longer a young man. I am, to be exact, fifty-eight years of age. (Je me nomme Louis Salavin.) Instead of growing more dispassionate about books, I find the contrary is taking place.

I'm a few years younger than Messrs. Miller and Salavin, but I share this vice of Miller's, as well as his conclusion. When you reach a certain age, you realize that admiration, affection, gratitude, and reverence, especially for a favorite book or author, are all to be cherished. You want to share them with everyone you meet.

Even so, I try to rein in my vice in the same way Miller himself knew he ought in his soberer moments, by having a lighter touch when I recommend. Broadcasting one's admiration and affection too enthusiastically often has the opposite effect to the one intended. The recipients either take the recommendation on its face and read with such high expectations that they will surely be disappointed, or they instinctively (if subconsciously) react with such skepticism that they read with an eye toward deflating the recommendation.

I will say that I have been enjoying The Books In My Life, from which the above passage comes. I've never read any of Miller's novels, only a Paris Review interview with him. This book about the books that shaped him has been a pleasant introduction to Miller's erudite and deeply personal style. Alas, the occasional doses of French are lost on me without the help of Google Translate.

Posted by Eugene Wallingford | Permalink | Categories: General, Personal

September 24, 2015 9:04 PM

Off to StrangeLoop

StrangeLoop 2010 logo

StrangeLoop 2015 starts tomorrow, and after a year's hiatus, I'm back. The pre-conference workshops were today, and I wish I could have been here in time for the Future of Programming workshop. Alas, I have a day job and had to teach class before hitting the road. My students knew I was eager to get away and bid me a quick goodbye as soon as we wrapped up our discussion of table-driven parsing. (They may also have been eager to finish up the scanners for their compiler project...)

As always, the conference line-up consists of strong speakers and intriguing talks throughout. Tomorrow, I'm looking forward to talks by Philip Wadler and Gary Bernhardt. Wadler is Wadler, and if anyone can shed new light in 2015 on the 'types versus unit tests' conflagration and make it fun, it's probably Bernhardt.

On Saturday, my attention is honed in on David Nolen's and Michael Bernstein's A History of Programming Languages for 2 Voices. I've been big fans of their respective work for years, swooning on Twitter and reading their blogs and papers, and now I can see them in person. I doubt I'll be able to get close, though; they'll probably be swamped by groupies. Immediately after that talk, Matthias Felleisen is giving a talk on Racket's big-bang, showing how we can use pure functional programming to teach algebra to middle school students and fold the network into the programming language.

Saturday was to begin with a keynote by Kathy Sierra, whom I last saw many years ago at OOPSLA. I'm sad that she won't be able to attend after all, but I know that Camille Fournier's talk about hopelessness and confidence in distributed systems design will be an excellent lead-off talk for the day.

I do plan one change for this StrangeLoop: my laptop will stay in its shoulder bag during all of the talks. I'm going old school, with pen and a notebook in hand. My mind listens differently when I write notes by hand, and I have to be more frugal in the notes I take. I'm also hoping to feel a little less stress. No need to blog in real time. No need to google every paper the speakers mention. No temptation to check email and do a little work. StrangeLoop will have my full attention.

The last time I came to StrangeLoop, I read Raymond Queneau's charming and occasionally disorienting "Exercises in Style", in preparation for Crista Lopes's talk about her exercises in programming style. Neither the book nor talk disappointed. This year, I am reading The Little Prince -- for the first time, if you can believe it. I wonder if any of this year's talks draw their inspiration from Saint-Exupéry? At StrangeLoop, you can never rule that kind of connection out.

Posted by Eugene Wallingford | Permalink | Categories: Computing, Personal

July 03, 2015 12:50 PM

Good Music Uses Your Whole Mind

A couple of months back, someone posted a link to an interview with guitarist Steve Vai, to share its great story about how Vai came to work with Frank Zappa. I liked the entire piece, including the first paragraph, which sets the scene on how Vai got into music in the first place:

Steve Vai: I recall when I was very, very young I was always tremendously excited whenever I was listening to the radio or records. Even back then a peculiar thing happened that still happens to me today. When I listen to music I can't focus on anything else. When there's wallpaper music on the radio it's not a problem but if a good song comes on it's difficult for me to carry on a conversation or multitask. It's always odd to me when I'm listening to something or playing something for somebody and they're having a discussion in the middle of a piece of music [laughs].

I have this pattern. When a song connects with me, I want to listen; not read or talk, simply listen. And, yes, sometimes it's "just" a pop song. For a while, whenever "Shut Up and Dance" by Walk the Moon came on the radio, it had my full attention. Ah, who am I kidding? It still has that effect on me.

Also, I love Vai's phrase "wallpaper music". I often work with music on in the background, and some music I like knows how to stay there. For me, that's a useful role for songs to play. Working in an environment with some ambient noise is much better for me than working in complete silence, and music makes better ambient noise for me than life in a Starbucks.

When I was growing up, I noticed that occasionally a good song would come on the air, and my level of concentration managed to hold it at bay. When I realized that I had missed the song, I was disappointed. Invariably in those cases, I had been solving a math problem or a writing a computer program. That must have been a little bit like the way Vai felt about music: I wanted to know how to do that, so I put my mind into figuring out how. I was lucky to find a career in which I can do that most of the time.

Oh, and by the way, Steve Vai can really play.

Posted by Eugene Wallingford | Permalink | Categories: General, Personal

March 06, 2015 11:29 AM

A Brief Return to the 18th Century

Petrov's Defense

I recently discovered that the students at my university have a chess club, so I stopped over yesterday to play a couple of games. In the first, my opponent played Philidor's Defense. In the second, I played Petrov's Defense. For a moment, I felt as if we had drifted in time to a Parisian cafe, circa 1770.

Then I looked up and saw a bank of TV screens surrounded by students who were drinking lattes and using cell phones to scroll through photos. I was back from my reverie.

Posted by Eugene Wallingford | Permalink | Categories: Personal

January 31, 2015 11:51 AM

Failure with a Purpose

I am committed to being wrong bigger and more often in 2015. Yet I am mindful of Avdi Grimm's admonition:

... failure isn't always that informative. You can learn a thousand different ways to fail and never learn a single way to succeed.

To fail for failure's sake is foolish and wasteful. In writing, the awful stuff you write when you start isn't usually valuable in itself, but rather for what we learn from studying and practicing. In science, failing isn't usually valuable in itself, but rather for what you learn when you prove an idea wrong. The scientist's mindset has a built-in correction for dealing with failure: every surprising result prompts a new attempt to understand why and build a better model.

As Grimm says, be sure you know what purpose your failure will serve. Sometimes, taking bigger risks intellectually can help us get off a plateau in our thinking, or even a local maximum. The failure pays off when we pay attention to the outcome and find a better hill to climb.

Posted by Eugene Wallingford | Permalink | Categories: General, Personal

January 29, 2015 4:27 PM

A Reminder from Marcus Aurelius

... from Book 6 of The Meditations, courtesy of George Berridge:

Item 52 from Book 6 of The Meditations, by Marcus Aurelius
You are not compelled to form any opinion about this matter before you, nor to disturb your piece of mind at all. Things in themselves have no power to extort a verdict from you.

This seems especially sound advice in this era, full of devices that enable other people to bombard our minds with matters they find Very Important Indeed. Maintain your piece of mind until you encounter a thing that your own mind knows to be important.

Posted by Eugene Wallingford | Permalink | Categories: General, Personal

January 18, 2015 10:26 AM

The Infinite Horizon

In Mathematics, Live: A Conversation with Laura DeMarco and Amie Wilkinson, Amie Wilkinson recounts the pivotal moment when she knew she wanted to be a mathematician. Insecure about her abilities in mathematics, unsure about what she wanted to do for a career, and with no encouragement, she hadn't applied to grad school. So:

I came back home to Chicago, and I got a job as an actuary. I enjoyed my work, but I started to feel like there was a hole in my existence. There was something missing. I realized that suddenly my universe had become finite. Anything I had to learn for this job, I could learn eventually. I could easily see the limits of this job, and I realized that with math there were so many things I could imagine that I would never know. That's why I wanted to go back and do math. I love that feeling of this infinite horizon.

After having written software for an insurance company during the summers before and after my senior year in college, I knew all too well the "hole in my existence" that Wilkinson talks about, the shrinking universe of many industry jobs. I was deeply interested in the ideas I had found in Gödel, Escher, Bach, and in the idea of creating an intelligent machine. There seemed no room for those ideas in the corporate world I saw.

I'm not sure when the thought of graduate school first occurred to me, though. My family was blue collar, and I didn't have much exposure to academia until I got to Ball State University. Most of my friends went out to get jobs, just like Wilkinson. I recall applying for a few jobs myself, but I never took the job search all that seriously.

At least some of the credit belongs to one of my CS professors, Dr. William Brown. Dr. Brown was an old IBM guy who seemed to know so much about how to make computers do things, from the lowest-level details of IBM System/360 assembly language and JCL up to the software engineering principles needed to write systems software. When I asked him about graduate school, he talked to me about how to select a school and a Ph.D. advisor. He also talked about the strengths and weaknesses of my preparation, and let me know that even though I had some work to do, I would be able to succeed.

These days, I am lucky even to have such conversations with my students.

For Wilkinson, DeMarco and me, academia was a natural next step in our pursuit of the infinite horizon. But I now know that we are fortunate to work in disciplines where a lot of the interesting questions are being asked and answers by people working in "the industry". I watch with admiration as many of my colleagues do amazing things while working for companies large and small. Computer science offers so many opportunities to explore the unknown.

Reading Wilkinson's recollection brought a flood of memories to mind. I'm sure I wasn't alone in smiling at her nod to finite worlds and infinite horizons. We have a lot to be thankful for.

Posted by Eugene Wallingford | Permalink | Categories: Computing, Personal, Teaching and Learning

January 01, 2015 11:29 AM

Being Wrong in 2015

Yesterday, I read three passages about being wrong. First, this from a blog entry about Charles Darwin's "fantastically wrong" idea for how natural selection works:

Being wildly wrong is perfectly healthy in science, because when someone comes along to prove that you're wrong, that's progress. Somewhat embarrassing progress for the person being corrected, sure, but progress nonetheless.

Then, P.G. Wodehouse shared in his Paris Review interview that it's not all Wooster and Jeeves:

... the trouble is when you start writing, you write awful stuff.

And finally, from a touching reflection on his novelist father, this delicious sentence by Colum McCann:

He didn't see this as a failure so much as an adventure in limitations.

My basic orientation as a person is one of small steps, small progress, trying to be a little less wrong than yesterday. However, such a mindset can lead to a conservatism that inhibits changes in direction. One goal I have for 2015 is to take bigger risks intellectually, to stretch my thinking more than I have lately. I'll trust Wodehouse that when I start, I may well be awful. I'll recall Darwin's example that it's okay to be wildly wrong, because then someone will prove me wrong (maybe even me), and that will be progress. And if, like McCann's father, I can treat being wrong as merely an adventure in my limitations, perhaps fear and conservatism won't hold me back from new questions worth asking.

Posted by Eugene Wallingford | Permalink | Categories: General, Personal

November 01, 2014 3:27 PM

Passion is a Heavy Burden

Mark Guzdial blogged this morning about the challenge of turning business teachers into CS teachers. Where is the passion? he asks.

These days, I wince every time I hear word 'passion'. We apply it to so many things. We expect teachers to have passion for the courses they teach, students to have passion for the courses they take, and graduates to have passion for the jobs they do and the careers they build.

Passion is a heavy burden. In particular, I've seen it paralyze otherwise well-adjusted college students who think they need to try another major, because they don't feel a passion for the one they are currently studying. They don't realize that often passion comes later, after they master something, do it for a while, and come to appreciate it ways they could never imagine before. I'm sure some of these students become alumni who are discontent with their careers, because they don't feel passion.

I think requiring all CS teachers to have a passion for CS sets the bar too high. It's an unrealistic expectation of prospective teachers and of the programs that prepare them.

We can survive without passionate teachers. We should set our sights on more realistic and relevant goals:

  • Teachers should be curious. They should have a desire to learn new things.
  • Teachers should be professional. They should have a desire to do their jobs well.
  • Teachers should be competent. They should be capable of doing their jobs well.

Curiosity is so much more important than passion for most people in most contexts. If you are curious, you will like encountering new ideas and learning new skills. That enjoyment will carry you a long way. It may even help you find your passion.

Perhaps we should set similarly realistic goals for our students, too. If they are curious, professional, and competent, they will most likely be successful -- and content, if not happy. We could all do worse.

Posted by Eugene Wallingford | Permalink | Categories: General, Personal, Teaching and Learning

October 22, 2014 4:32 PM

The Meaning of Life

... is determined by the moments when something happens.

In the end, a person doesn't view his [or her] life as merely the average of its moments -- which, after all, is mostly nothing much, plus some sleep. Life is meaningful because it is a story, and a story's arc is determined by the moments when something happens.

So writes Atul Gawande in Being Mortal: Medicine and What Matters in the End. When I am deep in a semester, preparing a course and doing all the things that a department head must do, both big small, the pace of life reaches a point where my mind is prone to go into cruise control. That's when I need to remind myself not to let my story become a stretch of uninterrupted white noise. I have to consciously step out of the blur and make something worthwhile -- and memorable -- happen.

Posted by Eugene Wallingford | Permalink | Categories: Personal

October 13, 2014 1:43 PM

Buckets, Tap Shoes, and Smaller Places

I was in St. Paul this weekend to visit my younger daughter for the first time since she started college six weeks ago. (It is hard to believe I dropped my older daughter off at school for the first time three years ago.)

Friday night, my daughter treated us to a performance by Buckets and Tap Shoes. The group blended dance, music, and seductive showmanship to create a show that kept me bouncing in rhythm for two hours. The dance and music were heavy on tap and drums, which let the performers play with rhythms. They also interacted with the crowd throughout the show, which set them up for an encore finale with twenty or more audience members on stage drumming, dancing, and generally into the rhythm. Impressive.

We like her school, and the Highland Park neighborhood is quite nice, but the Twin Cities are too big and busy for my tastes. I'm glad to live where I live.

Posted by Eugene Wallingford | Permalink | Categories: Personal

September 29, 2014 1:54 PM

"Classes I Control"

I saw a commercial recently for one of those on-line schools no one has ever heard of. In it, a non-traditional student with substantial job experience said, "At [On-Line U.], I can take classes I control."

I understand a desire for control, especially given the circumstances in which so many people go to university now. Late twenties or older, a family, a house, bills to pay. Under such conditions, school becomes a mercenary activity: get in, get a few useful skills and a credential, get out. Maximize ROI; minimize expenses.

In comparison, my years studying at a university were a luxury. I went to college straight out of high school, in a time with low tuition and even reasonable room and board. I was lucky to have a generous scholarship that defrayed my costs. But even my friends without scholarships seemed more relaxed about paying for school than students these days. It wasn't because Mom and Dad were picking up the tab, either; most of my friends paid their own way.

The cost was reasonable and as a result, perhaps, students of my era didn't feel quite the same need to control all of their classes. That is just as well, because we didn't have much control, nor much bargaining power to change how our professors worked.

What a fortunate powerlessness that was, though. In most courses, I encountered creative, intelligent professors. Once a year or so, I would walk into a course with rather pedestrian goals only to find that the professor had something different in mind, something unimagined, something wonderful. If naive, twenty-year-old Eugene had had control of all his courses, he would likely have missed out on a few experiences that changed his life.

What a great luxury it was to surrender control for eleven weeks and be surprised by new knowledge, ideas, and possibilities -- and by the professors who made the effort to take me there.

I know was lucky in a lot of ways, and for that I am thankful. I hope that our inability or unwillingness to keep public university affordable doesn't have as an unintended casualty the wonderful surprises that can happen in our courses.

Posted by Eugene Wallingford | Permalink | Categories: Personal, Teaching and Learning

September 03, 2014 4:13 PM

My PhD Advisor Takes on a New Challenge

Just this week I learned that Jon Sticklen, my PhD advisor, has moved to Michigan Tech to chair its Department of Engineering Fundamentals. As I recall, Michigan Tech focuses much of its effort on undergraduate engineering education. This makes it a good fit for Jon, who has been working on projects in engineering education at Michigan State for a number of years now, with some success. I wish him and them well.

By the way, if you can handle a strong winter, then Tech can be a great place to live. The upper peninsula of Michigan is stunning!

Posted by Eugene Wallingford | Permalink | Categories: Personal, Teaching and Learning

August 16, 2014 10:19 AM

Channeling Virginia Woolf

In her diary, Woolf once secured in words a state of mind that has waylaid me recently.

Still if one is Prometheus, if the rock is hard and the gadflies pungent, gratitude, affection, none of the nobler feelings have sway. And so this August is wasted.

And yet hope remains. August is but half past.


(From an entry dated Tuesday, August 18, 1921, in A Writer's Diary.)

Posted by Eugene Wallingford | Permalink | Categories: Personal

July 10, 2014 3:08 PM

The Passing of the Postage Stamp

In this New York Times article on James Baldwin's ninetieth birthday, scholar Henry Louis Gates laments:

On one hand, he's on a U.S. postage stamp; on the other hand, he's not in the Common Core.

I'm not qualified to comment on Baldwin and his place in the Common Core. In the last few months, I read several articles about and including Baldwin, and from those I have come to appreciate better his role in twentieth-century literature. But I also empathize with anyone trying to create a list of things that every American should learn in school.

What struck me in Gates's comment was the reference to the postage stamp. I'm old enough to have grown up in a world where the postage stamp held a position of singular importance in our culture. It enabled communication at a distance, whether geographical or personal. Stamps were a staple of daily life.

In such a world, appearing on a stamp was an honor. It indicated a widespread acknowledgment of a person's (or organization's, or event's) cultural impact. In this sense, the Postal Service's decision to include James Baldwin on a stamp was a sign of his importance to our culture, and a way to honor his contributions to our literature.

Alas, this would have been a much more significant and visible honor in the 1980s or even the 1990s. In the span of the last decade or so, the postage stamp has gone from relevant and essential to archaic.

When I was a boy, I collected stamps. It was a fun hobby. I still have my collection, even if it's many years out of date now. Back then, stamp collecting was a popular activity with a vibrant community of hobbyists. For all I know, that's still true. There's certainly still a vibrant market for some stamps!

But these days, whenever I use a new stamp, I feel as if I'm holding an anachronism in my hands. Computing technology played a central role in the obsolescence of the stamp, at least for personal and social communication.

Sometimes people say that we in CS need to a better job helping potential majors see the ways in which our discipline can be used to effect change in the world. We never have to look far to find examples. If a young person wants to be able to participate in how our culture changes in the future, they can hardly do better than to know a little computer science.

Posted by Eugene Wallingford | Permalink | Categories: Computing, General, Personal

July 09, 2014 12:35 PM

Why I Blog, Ten Years On

A blog can be many things.

It can an essay, a place to work out what I think, in the act of writing.

It can be a lecture, a place to teach something, however big or small, in my own way.

It can be memoir, a place to tell stories about my life, maybe with a connection to someone else's story.

It can be a book review or a conference review, a place to tell others about something I've read or seen that they might like, too. Or not.

It can be an open letter, a place to share news, good or bad, in a broadcast that reaches many.

It can be a call for help, a request for help from anyone who receives the message and has the time and energy to respond.

It can be a riff on someone else's post. I'm not a jazz musician, but I like to quote the melodies in other people's writing. Some blog posts are my solos.

It can be a place to make connections, to think about how things are similar and different, and maybe learn something in the process.

A blog is all of these, and more.

A blog can also be a time machine. In this mode, I am the reader. My blog reminds me who I was at another time.

This effect often begins with a practical question. When I taught agile software development this summer, I looked back to when I taught it last. What had I learned then but forgotten since? How might I do a better job this time around?

When I visit blog posts from the past, though, something else can happen. I sometimes find myself reading on. The words mesmerize me and pull me forward on the page, but back in time. It is not that the words are so good that I can't stop reading. It's that they remind me who I was back then. A different person wrote those words. A different person, yet me. It's quite a feeling.

A blog can combine any number of writing forms. I am not equally good writing in all of these forms, or even passably good in any of them. But they are me. Dave Winer has long said that a blog is the unedited voice of a person. This blog is the unedited voice of me.

When I wrote my first blog post ten years ago today, I wasn't sure if anyone wanted to hear my voice. Over the years, I've had the good fortune to interact with many readers, so I know someone is listening. That still amazes me. I'm glad that something you read here is worth the visit.

Back in those early days, I wondered if it even mattered whether anyone else would read. The blog as essay and as time machine are valuable enough on their own to make writing worth the effort to me. But I'll be honest: it helps a lot knowing that other people are reading. Even when you don't send comments by e-mail, I know you are there. Thank you for your time.

I don't write as often as I did in the beginning. But I still have things to say, so I'll keep writing.

Posted by Eugene Wallingford | Permalink | Categories: General, Personal

February 13, 2014 4:25 PM

Politics in a CS Textbook

Earlier this week, I looking for inspiration for an exam problem in my algorithms course. I started thumbing through a text I briefly considered considering for adoption this semester. (I ended up opting for no text without considering any of them very deeply.)

No Politics warning sign -- handmade

The first problem I read was written with a political spin, at the expense of one of the US political parties. I was aghast. I tweeted:

This textbook uses an end-of-chapter exercise to express an opinion about a political party. I will no longer consider it for adoption.

I don't care which party is made light of or demeaned. I'm no longer interested. I don't want a political point unrelated to my course to interfere with my students' learning -- or with the relationship we are building.

In general, I don't want students to think of me in a partisan way, whether the topic is politics, religion, or anything else outside scope of computer science. It's not my job as a CS instructor to make my students uncomfortable.

That isn't to say that I want students to think of me as bland or one-dimensional. They know me to be a sports fan and a chess player. They know I like to read books and to ride my bike. I even let them know that I'm a Billy Joel fan. All of these give me color and, while they may disagree with my tastes, none of these are likely to create distance between us.

Nor do I want them to think I have no views on important public issues of the day. I have political opinions and actually like to discuss the state of the country and world. Those discussions simply don't belong in a course on algorithms or compiler construction. In the context of a course, politics and religion are two of many unnecessary distractions.

In the end, I did use the offensive problem, but only as inspiration. I wrote a more generic problem, the sort you expect to see in an algorithms course. It included all the relevant features of the original. My problem gave the students a chance to apply what they have have learned in class without any noise. The only way this problem could offend students was by forcing them to demonstrate that they are not yet ready to solve such a problem. Alas, that is an offense that every exam risks giving.

... and yes, I still owe you a write-up on possible changes to the undergraduate algorithms canon, promised in the entry linked above. I have not forgotten! Designing a new course for spring semester is a time-constrained operation.

Posted by Eugene Wallingford | Permalink | Categories: Personal, Teaching and Learning

February 12, 2014 11:49 AM

They Are Always Watching

Rand's Inbox Reboot didn't do much for me on the process and tool side of things, perhaps other than rousing a sense of familiarity. Been there. The part that stood out for me was when he talked about the ultimate effect of not being in control of the deluge:

As a leader, you define your reputation all the time. You'd like to think that you could choose the moments that define your reputation, but you don't. They are always watching and learning. They are always updating their model regarding who you are and how you lead with each observable action, no matter how large or small.

He was speaking of technical management, so I immediately thought about my time as department head and how true this passage is.

But it is also true -- crucially true -- of the relationship teachers have with their students. There are few individual moments that define how a teacher is seen by his or her students. Students are always watching and learning. They infer things about the discipline and about the teacher from every action, from every interaction. What they learn in all the little moments comes to define you in their minds.

Of course, this is even more true of parents and children. To the extent I have any regrets as a parent, it is that I sometimes overestimated the effect of the Big Moments and underestimated the effect of all those Little Moments, the ones that flow by without pomp or recognition. They probably shaped my daughters, and my daughters' perception of me, more than anything particular action I took.

Start with a good set of values, then create a way of living and working that puts these values at the forefront of everything you do. Your colleagues, your students, and your children are always watching.

Posted by Eugene Wallingford | Permalink | Categories: Managing and Leading, Personal, Teaching and Learning

February 03, 2014 4:07 PM

Remembering Generosity

For a variety of reasons, the following passage came to mind today. It is from a letter that Jonathan Schoenberg wrote as part of the "Dear Me, On My First Day of Advertising" series on The Egotist forum:

You got into this business by accident, and by the generosity of people who could have easily been less generous with their time. Please don't forget it.

It's good for me to remind myself frequently of this. I hope I can be as generous with time to my students and colleagues as as so many of my professors and colleagues were with their time. Even when it means explaining nested for-loops again.

Posted by Eugene Wallingford | Permalink | Categories: General, Personal

December 16, 2013 2:20 PM

More Fun with Integer "Assembly Language": Brute-Forcing a Function Minimum

Or: Irrational Exuberance When Programming

My wife and daughter laughed at me yesterday.

A few years ago, I blogged about implementing Farey sequences in Klein, a language for which my students at the time were writing a compiler. Klein was a minimal functional language with few control structures, few data types, and few built-in operations. Computing rational approximations using Farey's algorithm was a challenge in Klein that I likened to "integer assembly programming".

I clearly had a lot of fun with that challenge, especially when I had the chance to watch my program run using my students' compilers.

This semester, I am again teaching the compiler course, and my students are writing a compiler for a new version of Klein.

Last week, while helping my daughter with a little calculus, I ran across a fun new problem to solve in Klein:

the task of optimizing cost across the river

There are two stations on opposite sides of a river. The river is 3 miles wide, and the stations are 5 miles apart along the river. We need to lay pipe between the stations. Pipe laid on land costs $2.00/foot, and pipe laid across the river costs $4.00/foot. What is the minimum cost of the project?

This is the sort of optimization problem one often encounters in calculus textbooks. The student gets to construct a couple of functions, differentiate one, and find a maximum or minimum by setting f' to 0 and solving.

Solving this problem in Klein creates some of challenges. Among them are that ideally it involves real numbers, which Klein doesn't support, and that it requires a square root function, which Klein doesn't have. But these obstacles are surmountable. We already have tools for computing roots using Newton's method in our collection of test programs. Over a 3mi-by-5mi grid, an epsilon of a few feet approximates square roots reasonably well.

My daughter's task was to use the derivative of the cost function but, after talking about the problem with her, I was interested more in "visualizing" the curve to see how the cost drops as one moves in from either end and eventually bottoms out for a particular length of pipe on land.

So I wrote a Klein program that "brute-forces" the minimum. It loops over all possible values in feet for land pipe and compares the cost at each value to the previous value. It's easy to fake such a loop with a recursive function call.

The programmer's challenge in writing this program is that Klein has no local variables other function parameters. So I had to use helper functions to simulate caching temporary variables. This allowed me to give a name to a value, which makes the code more readable, but most importantly it allowed me to avoid having to recompute expensive values in what was already a computationally-expensive program.

This approach creates another, even bigger challenge for my students, the compiler writers. My Klein program is naturally tail recursive, but tail call elimination was left as an optional optimization in our class project. With activation records for all the tail calls stored on the stack, a compiler has to use a lot of space for its run-time memory -- far more than is available on our default target machine.

How many frames do we need? Well, we need to compute the cost at every foot along a (5 miles x 5280 feet/mile) rectangle, for a total of 26,400 data points. There will, of course, be other activation records while computing the last value in the loop.

Will I be able to see the answer generated by my program using my students' compilers? Only if one or more of the teams optimized tail calls away. We'll see soon enough.

So, I spent an hour or so writing Klein code and tinkering with it yesterday afternoon. I was so excited by the time I finished that I ran upstairs to tell my wife and daughter all about it: my excitement at having written the code, and the challenge it sets for my students' compilers, and how we could compute reasonable approximations of square roots of large integers even without real numbers, and how I implemented Newton's method in lieu of a sqrt, and...

That's when my wife and daughter laughed at me.

That's okay. I am programmer. I am still excited, and I'd do it again.

Posted by Eugene Wallingford | Permalink | Categories: Computing, Personal, Teaching and Learning

November 26, 2013 1:38 PM

Saying Thanks, and Giving Back

When someone asked Benjamin Franklin why he had declined to seek a patent for his famous stove, he said:

I declined it from a principle which has ever weighed with me on such occasions, that as we enjoy great advantages from the inventions of others, we should be glad of an opportunity to serve others by any invention of ours.

This seems a fitting sentiment to recall as I look forward to a few days of break with my family for Thanksgiving. I know I have a lot to be thankful for, not the least of which are the inventions of so many others that confer great advantage on me. This week, I give thanks for these creations, and for the creators who shared them with me.

Posted by Eugene Wallingford | Permalink | Categories: General, Personal

November 10, 2013 9:10 AM

You May Be a Teacher If ...

... you wake groggily at 5:30 on a Sunday morning. You lie in bed, half awake, as your mind begins designing a new class session for your compiler course. You never go back to sleep.

Before you rise, you have a new reading assignment, an opening exercise asking your students to write a short assembly language program, and two larger in-class exercises aimed at helping them make a good start on their compiler's run-time system.

This is a thorny topic. It's been bothering you. Now, you have a plan.

Posted by Eugene Wallingford | Permalink | Categories: Personal, Teaching and Learning

October 12, 2013 11:27 AM

StrangeLoop: This and That, Volume 3

[My notes on StrangeLoop 2013: Table of Contents]

Six good talks a day is about my limit. Seven for sure. Each creates so much mental activity that my brain soon loses the ability to absorb more. Then, I need a walk.


After Jenny Finkel's talk on machine, someone asked if Prismatic's system had learned any features or weights that she found surprising. I thought her answer was interesting. I paraphrase: "No. As a scientist, you should understand why the system is the way that it is, or find the bug if it shouldn't be that way."

In a way, this missed the point. I'm guessing the questioner was looking to hear about a case that required them to dig in because the answer was correct but they didn't know why yet, or incorrect and the bug wasn't obvious. But Finkel's answer shows how matter-of-fact scientists can be about what they find. The world is as it is, and scientists try to figure out why. That's all.


The most popular corporate swag this year was stickers to adorn one's laptop case. I don't put stickers on my gear, but I like looking at other people's stickers. My favorites were the ones that did more than simply display the company name. Among them were asynchrony:

asynchrony laptop sticker

-- which is a company name but also a fun word in its own right -- and data-driven:

O'Reilly laptop sticker

-- by O'Reilly. I also like the bound, graph-paper notebooks that O'Reilly hands out. Classy.


In a previous miscellany I mentioned Double Multitasking Guy. Not me, not this time. I carried no phone, as usual, and this time I left my laptop back in the hotel room. Not having any networked technology in hand creates a different experience, if not a better one.

Foremost, having no laptop affects my blogging. I can't take notes as quickly, or as voluminously. One of the upsides of this is that it's harder for me to distract myself by writing complete sentences or fact-checking vocabulary and URLs. Quick, what is the key idea here? What do I need to look up? What do I need to learn next?


With video recording now standard at tech conferences, and with StrangeLoop releasing its videos so quickly now, a full blow-by-blow report of each talk becomes somewhat less useful. Some people find summary reports helpful, though, because they don't want to watch the full talks or have the time to do so. Short reports let these folks keep their pulse on the state of the world. Others are looking for some indication of whether they want to invest the time to watch.

For me, the reports serve another useful purpose. They let me do a little light analysis and share my personal impressions of what I hear and learn. Fortunately, that sort of blog entry still finds an audience.

Posted by Eugene Wallingford | Permalink | Categories: General, Personal

September 06, 2013 8:37 AM

Old Enough to Know

A trip to my alma mater for a reunion this weekend brings to mind these words from Roger Ebert:

There is a part of me that will forever want to be walking under autumn leaves, carrying a briefcase containing the works of Shakespeare and Yeats and a portable chess set. I will pass an old tree under which once on a summer night I lay on the grass with a fragrant young woman and we quoted e.e. cummings back and forth.

I was more likely carrying Keats than Yeats and quoting Voltaire than cummings, but the feeling's the same. There is something about the age as we enter adulthood that becomes permanent in us, more so than any other time. I'm old enough to know that these memories can't hurt a thing.

I sent one daughter off to college a couple of years ago and will send another next year. In this experience, I feel more like the wistful father who penned My Dear Son. Indeed, "every age has its gifts for the man who is willing to work for them and use them temperately".


Attributions. The Ebert passage comes from his review of the film Liberal Arts. (Ebert calls it "an almost unreasonable pleasure"; I agree.) John Mellencamp wrote the line "old enough to know...".

Posted by Eugene Wallingford | Permalink | Categories: Personal

July 17, 2013 1:41 PM

And This Gray Spirit Yearning

On my first day as a faculty member at the university, twenty years ago, the department secretary sent me to Public Safety to pick up my office and building keys. "Hi, I'm Eugene Wallingford," I told the person behind the window, "I'm here to pick up my keys." She smiled, welcomed me, and handed them to me -- no questions asked.

Back at the department, I commented to one of my new colleagues that this seemed odd. No one asked to see an ID or any form of authorization. They just handed me keys giving me access to a lot of cool stuff. My colleague shrugged. There has never been a problem here with unauthorized people masquerading as new faculty members and picking up keys. Until there is a problem, isn't it nice living in a place where trust works?

Things have changed. These days, we don't order keys for faculty; we "request building access". This phrase is more accurate than a reference to keys, because it includes activating the faculty ID to open electronically-controlled doors. And we don't simply plug a new computer into an ethernet jack and let faculty start working; to get on the wireless network, we have to wait for the Active Directory server to sync with the HR system, which updates only after electronic approval of a Personnel Authorization Form that set up of the employee's payroll record. I leave that as a run-on phrase, because that's what living it feels like.

The paperwork needed to get a new faculty member up and running these days reminds me just how simple life was when in 1992. Of course, it's not really "paperwork" any more.

Posted by Eugene Wallingford | Permalink | Categories: Computing, Personal

July 07, 2013 9:32 AM

Interesting Sentences, Personal Weakness Edition

The quest for comeuppance is a misallocation of personal resources. -- Tyler Cowen

Far too often, my reaction to events in the world around me is to focus on other people not following rules, and the unfairness that results. It's usually not my business, and even when it is, it's a foolish waste of mental energy. Cowen expresses this truth nicely in neutral, non-judgmental language. That may help me develop a more productive mental habit.

What we have today is a wonderful bike with training wheels on. Nobody knows they are on, so nobody is trying to take them off. -- Alan Kay, paraphrased from The MIT/Brown Vannevar Bush Symposium

Kay is riffing off Douglas Engelbart's tricycle analogy, mentioned last time. As a computer scientist, and particularly one fortunate enough to have been exposed to the work of Ivan Sutherland, Englebart, Kay and the Xerox PARC team, and so many others, I should be more keenly conscious that we are coasting along with training wheels on. I settle for limited languages and limited tools.

Even sadder, when computer scientists and software developers settle for training wheels, we tend to limit everyone else's experience, too. So my apathy has consequences.

I'll try to allocate my personal resources more wisely.

Posted by Eugene Wallingford | Permalink | Categories: Computing, Personal

May 08, 2013 12:11 PM

Not So Random Sentences

I start with a seemingly random set of sentences to blog about and, in the process of writing about them, find that perhaps they aren't so random after all.

An Era of Sharing Our Stuff

Property isn't theft; property is an inefficient distribution of resources.

This assertion comes from an interesting article on "economies of scale as a service", in reaction to a Paul Graham tweet:

Will ownership turn out to be largely a hack people resorted to before they had the infrastructure to manage sharing properly?

Open-source software, the Creative Commons, crowdsourcing. The times they are a-changin'.

An Era of Observing Ourselves

If the last century was marked by the ability to observe the interactions of physical matter -- think of technologies like x-ray and radar -- this century is going to be defined by the ability to observe people through the data they share.

... from The Data Made Me Do It.

I'm not too keen on being "observed" via data by every company in the world, even as understand the value it can brings the company and even me. But I like very much the idea that I can observe myself more easily and more productively. For years, I collected and studied data about my running and used what I learned to train and race better. Programmers are able to do this better now than ever before. You can learn a lot just by watching.

An Era of Thinking Like Scientist

... which leads to this line attributed to John C. Reynolds, an influential computer scientist who passed away recently:

Well, we know less than we did before, but more of what we know is actually true.

It's surprising how easy it is to know stuff when we don't have any evidence at all. Observing the world methodically, building models, and comparing them to what we observe in the future helps to know less of the wrong stuff and more of the right stuff.

Not everyone need be a scientist, but we'd all be better off if more of us thought like a scientist more often.

Posted by Eugene Wallingford | Permalink | Categories: Computing, Patterns, Personal

May 03, 2013 3:37 PM

A Participator in the Panorama of Nature

John Burroughs, in "The Exhilarations of the Road" (1895):

[The walker] is not isolated, but one with things, with the farms and industries on either hand. The vital, universal currents play through him. He knows the ground is alive; he feels the pulses of the wind, and reads the mute language of things. His sympathies are all aroused; his senses are continually reporting messages to his mind. Wind, frost, ruin, heat, cold, are something to him. He is not merely a spectator of the panorama of nature, but a participator in it. He experiences the country he passes through--tastes it, feels it, absorbs it; the traveller in his fine carriage sees it merely.

Knee surgery ended my avocation as a runner. I used to walk a lot, too, but these days I walk even more than I used to. For more than a year, I have walked to and from work almost every day, even through the Iowa winter. As both runner and walker, I recognize the exhilaration Burroughs describes. I find that I appreciate the elements rather than curse them. Wind and frost, rain and snow, heat and cold all matter. Why complain about a driving rain? The world is alive around me.

(I found Burroughs's passage in Solvitur Ambulando, a discourse on the virtues of walking in the spirit of Thoreau. I love the title as well as the essay.)

Posted by Eugene Wallingford | Permalink | Categories: Personal, Running

April 20, 2013 10:25 AM

Reminiscing about Making My First Computer

Steve Wozniak

A friend put a copy of GameInformer magazine in my box yesterday with a pointer to an interview with the Great and Powerful Woz, Steve Wozniak. It's a short interview, only two pages, but it reminded me just how many cool things Wozniak (and so many others) did in the mid-1970s. It also reminded me of my younger days, coming into contact with the idea of games and machine learning for the first time.

Woz described how, after seeing Pong in a video arcade, he went home and built his own Pong game out of twenty-eight $1 chips. Steve Jobs took the game to Atari, where he encountered Nolan Bushnell, who had an idea for a single-player version of Pong. Thus did Woz design Breakout, a game with an especially apt name. It helped define Apple Computer.

The thought of building a computer game out of chips still amazes me. I was never a hardware guy growing up. I never had access to computer chips or that culture, and I had little inclination to fiddle with electronics, save for a few attempts to take apart radios and put them back together. When I designed things as a kid, they were houses or office buildings. I was going to be an architect. But Woz's story reminded me of one experience that foreshadowed my career as a computer scientist.

One year in school, I won a math contest. First prize was a copy of The Unexpected Hanging and Other Mathematical Diversions, a collection of Martin Gardner's columns from Scientific American. Chapter 8 was called "A Matchbox Game-Learning Machine". It described Hexapawn, a game played on a 3x3 board with chess pawns. The game was no more complex than Tic Tac Toe, but it was new. And I loved board games.

Gardner's article had more in store for me, though, than simply another game to study. He described how to create a "computer" -- a system of matchboxes -- that learns how to play the game! Here's how:

You make one box for each possible board position. In the box, you put different colored marbles corresponding to the moves that can be played in the position. Then you play a bunch of games against the matchbox computer. When it is the computer's turn to move, you pick up the box for that board position, shake it, and see which marble lands in the lower-right corner of the box. That's the computer's move.

When the game is over, the computer gets feedback. If it won the game, then put all the marbles back in their boxes. If it lost, punish it by keeping the marble responsible for its last move; put all the rest back in their boxes. Gardner claimed that by following this strategy, the matchbox computer would learn to play a perfect game in something under fifty moves.

This can't possibly work, can it? So I built it. And it did learn. I was happy, and amazed.

I remember experimenting a bit. Maybe a move wasn't always a loser? So I seeded the computer with more than one marble for each candidate move, so that the computer could overcome bad luck. Hexapawn is so simple that this wasn't necessary -- losing moves are losing moves -- but the computer still learned to play a perfect game, just a bit slower than before.

This is one of the earliest experiences I remember that started me down the road of studying artificial intelligence. Reading copious amounts of science fiction pushed me in that direction, too, but this was different. I had made something, and it learned. I was hooked.

So, I wasn't a hardware kid, but I had a hardware experience. It just wasn't digital hardware. But my inclination was always more toward ideas than gadgets. My interests quickly turned to writing programs, which made it so much easier to tinker with variations and to try brand-new ideas.

(Not so quickly, though, that I turned away from my dream of being an architect. The time I spent in college studying architecture turned out to be valuable in many ways.)

Wozniak was a hardware guy, but he quickly saw the potential of software. "Games were not yet software, and [the rise of the microprocessor] triggered in my mind: microprocessors can actually program games." He called the BASIC interpreter he wrote "Game BASIC". Ever the engineer, he designed the Apple II with integrated hardware and software so that programmers could write cool games.

I don't have a lot in common with Steve Wozniak, but one thing we share is the fun we have playing games. And, in very different ways, we once made computers that changed our lives.


The GameInformer interview is on-line for subscribers only, but there is a cool video of Wozniak playing Tetris -- and talking about George H.W. Bush and Mikhail Gorbachev!

Posted by Eugene Wallingford | Permalink | Categories: Computing, Personal

January 01, 2013 4:22 PM

Of Course, It's January Again

My workout at dawn this New Year's Day brought me the following passage, from Dave Winer:

... it gets ridiculous near the end, time runs so fast, it's December just after it's January and then of course it's January again, until there's no more time.

Time goes by quickly, whether we use it well or not. We may as well use the time we have to its fullest, until there's no more time.

I spent part of my morning playing at the intersection of today and yesterday. My wife gave me a USB-equipped turntable for Christmas, which will be handy for converting some music I have on vinyl LPs to digital format. With so much music streaming on the internet these days, it's hard to believe that there is anything not available on CD or iTunes. Even when a remastered CD is available, though, sometimes it's more fun to spin the vinyl record, convert it to something more "modern", and fiddle with the resulting file to get just the right sound.

May the blink of an eye that is 2013 bring you manifold opportunities to build things and tear them down, and may you have a lot of fun along the way.

Posted by Eugene Wallingford | Permalink | Categories: Personal

November 23, 2012 9:34 AM

In the Spirit of the Weekend

I am thankful for human beings' capacity to waste time.

We waste it in the most creative ways. My life is immeasurably better because other people have wasted time and created art and literature. Even much of the science and technology I enjoy came from people noodling around in their free time. The universe has blessed me, and us.


At my house, Thanksgiving lasts the whole weekend. I don't mind writing a Thanksgiving blog the day after, even though the rest of the world has already moved on to Black Friday and the next season on the calendar. My family is, I suppose, wasting time.

This note of gratitude was prompted by reading a recent joint interview with Brian Eno and Ha-Joon Chang, oddities in their respective disciplines of music and economics. I am thankful for oddities such as Eno and Chang, who add to the world in ways that I cannot. I am also thankful that I live in a world that provides me access to so much wonderful information with such ease. I feel a deep sense of obligation to use my time in a way that repays these gifts I have been given.

Posted by Eugene Wallingford | Permalink | Categories: General, Personal

August 27, 2012 12:53 PM

My Lack of Common Sense

In high school, I worked after school doing light custodial work for a local parochial school for a couple of years. One summer, a retired guy volunteered to lead me and a couple of other kids doing maintenance projects at the school and church.

One afternoon, he found me in trying to loosen the lid on a paint can using one of my building keys. Yeah, that was stupid. He looked at me as if I were an alien, got a screwdriver, and opened the can.

Later that summer, I overheard him talking to the secretary. She asked how I was working out, and he said something to the effect of "nice kid, but he has no common sense".

That stung. He was right, of course, but no one likes to be thought of as not capable, or not very smart. Especially someone who likes to be someone who knows stuff.

I still remember that eavesdropped conversation after all these years. I knew just what he meant at the time, and I still do. For many years I wondered, what was wrong with me?

It's true that I didn't have much common sense as a handyman back then. To be honest, I probably still don't. I didn't have much experience doing such projects before I took that job. It's not something I learned from my dad. I'd never seen a bent key before, at least not a sturdy house key or car key, and I guess it didn't occur to me that one could bend.

The A student in me wondered why I hadn't deduced the error of my ways from first principles. As with the story of Zog, it was immediately obvious as soon as it was pointed out to me. Explanation-based learning is for real.

Over time, though, I have learned to cut myself some slack. Voltaire was right: Common sense is not so common. These days, people often say that to mean there are far too many people like me who don't have the sense to come in out of the rain. But, as the folks at Wikipedia recognize, that sentence can mean something else even more important. Common sense isn't shared whenever people have not had the same experiences, or have not learned it some other way.

Maybe there are still some things that most of us can count on as common, by virtue of living in a shared culture. But I think we generally overestimate how much of any given person's knowledge is like that. With an increasingly diverse culture, common experience and common cultural exposure are even harder to come by.

That gentleman and secretary probably forgot about their conversation within minutes, but the memory of his comment still stings a little. I don't think I'd erase the memory, though, even if I could. Every so often, it reminds me not to expect my students to have too much common sense about programs or proofs or programming languages or computers.

Maybe they just haven't had the right experiences yet. It's my job to help them learn.

Posted by Eugene Wallingford | Permalink | Categories: Personal, Teaching and Learning

July 25, 2012 4:09 PM

I Gotta Get More Famous...

Duncan Davidson tweeted a check of Google search suggestions for his name. Now, Duncan's a well known guy in a certain corner of the technical world, but he didn't even crack the top six:

a NameSurfer cap of the popularity of Eugene versus Duncan

A spell-corrected "dunkin donuts" did, though. Ha.

Hey, why not try "Eugene"? Until 1970, it was a much more common first name for boys than "Duncan":

a NameSurfer cap of the popularity of Eugene versus Duncan

I'll bet you didn't know that Eugene had ever been so popular! Alas, since 1930, it has been in steady decline. Duncan, on the other hand, has been on the rise since 1970 and passed Eugene in 2000. I haven't grabbed 2010 data to update my Name Surfer app, but I'm sure the recent trajectories have continued.


top ten Google search suggestions for 'eugene'

Eugene, Oregon, is my Duncan Hines.

I don't make my first appearance in the top ten until we get to "eugene wal":

top ten Google search suggestions for 'eugene wal'

One more letter vaults me near the top of the list:

top ten Google search suggestions for 'eugene wall'

Finally, we add an 'i' and push the pesky Eugene Wallace off his throne. Indeed, I begin to dominate:

top ten Google search suggestions for 'eugene walli'

Even so, my blog barely nudges past Mr. Wallace. I am so unpopular that Google would rather believe users have misspelled his name than believe they are looking for my Twitter page.

I think I'd better start working on my legacy.

Posted by Eugene Wallingford | Permalink | Categories: Personal

May 15, 2012 3:22 PM

What Teachers Make

Last night I attended my daughter's high school orchestra concert. (She plays violin.) Early on I found myself watching the conductor rather than the performers. He was really into the performance, as many conductors are. He's a good teacher and gets pretty good sound out of a few dozen teenagers. Surely he must be proud of their performance, and at least a little proud of his own.

Maybe it's just the end of another academic year, but my next thought was, "This concert will be over in an hour." My mind flashed to a movie from the 1990s, Mr. Holland's Opus. What does the conductor feel like when it's over? Is there a sense of emptiness? What does he think about, knowing that he'll being doing this all again next year, just as he did last year? The faces will change, and maybe the musical selections, but the rest will be eerily familiar.

Then it occurred to me: This is the plight of every teacher. It is mine.

Sometimes I envy people who make things for a living. They create something that people see and use. In the case of software, they may have the opportunity to grow their handiwork, to sustain it. It's tangible. It lasts, at least for a while.

Teachers live in a different world. I think about my own situation, teaching one class a semester, usually in our upper division. Every couple of years, I see a new group of students. I have each of them in class once or twice, maybe even a few times. Then May comes, and they graduate.

To the extent that I create anything, it resides in someone else. In this way, being a teacher less like being a writer or a creator and more like being a gardener. We help prepare others to make and do.

Like gardeners, we plant seeds. Some fall on good soil and flourish. Some fall on rocks and die. Sometimes, you don't even know which is which; you find out only years later. I have been surprised in both ways, more often pleasantly than not.

Sure, we build things, too. We CS profs write software. We university profs build research programs. These are tangible products, and they last for a while.

(We administrators create documents and spreadsheets. Let's not go there.)

But these products are not our primary task, at least not at schools like mine. It is teaching. We help students exercise their minds and grow their skills. If we are lucky, we change them in ways that go beyond our particular disciplines.

There is a different sort of rhythm to being a teacher than to being a maker. You need to be able to delay gratification, while enjoying the connections you make with students and ideas. That's one reason it's not so easy for just anyone to be a teacher, at least not for an entire career. My daughter's orchestra teacher seems to have that rhythm. I have been finding this rhythm over the course of my career, without quite losing the desire also to make things I can touch and use and share.

Posted by Eugene Wallingford | Permalink | Categories: Personal, Teaching and Learning

March 04, 2012 9:34 AM

One Year Later

March 4, 2011, was a Friday like any other. I had fallen into a comfortable weekly routine: easy 5-milers on Tuesday and Thursday, a medium 7-miler on Wednesday, a hard 8 miles on the indoor track on Friday, and 8 miles on Sunday. February had been snowy and cold, which made my preferred 12-mile long run on Sundays a bit too much. In place of those miles, I ran a little faster on Fridays and looked forward to the coming spring thaw.

The morning was crisp and the roads clearer than they had been, so I decided to run outdoors. I picked out my favorite 8-mile route, an old friend I had first met when we lived on the other side of town. It passed by our new house, too, and so made the move with us.

It was an excellent run. Footing on hills and in curves is the big challenge of running outdoors in winter, so I didn't worry about pace. I breathed in the cold air, took in the old sights, and felt my body reach equilibrium with the elements.

the road to nowhere

I did not know at the time, but this would be my last run.

A flu that had been going around hit me later that day, and I was in bed sick for a few days. Then one morning, as I was starting to feel better, I woke up with a sore knee. No big deal, I thought; I'll take advantage of the extra day to be sure I've really licked that flu.

The flu left, but the knee pain did not. It got worse. I eventually went to see a specialist, who gave me the bad news, operated, gave me some more bad news, and operated a second time.

Since then, I have been rehabbing, slowly adding time and effort to my work-outs. But I have not run.

Two days ago, another first Friday of March, 52 weeks later, I had my best post-running workout yet. I still have far to go. The knee is still a little swollen, and it stiffens up after the shortest bouts of inactivity. It feels funny. But I see light.

There are days when I still feel that old urge to lace up my Asics GT-2100s and take off. I expect that summer bring plenty more of those days. The long road to who-knows-where stretches out before me as always, but I won't be exploring it on the run.

Posted by Eugene Wallingford | Permalink | Categories: Personal, Running

January 08, 2012 9:57 AM

Another Shovel Of Dirt

This morning, I did something I hadn't done since Sunday, February 27. I did a long workout. That day, it was a 12-mile run in single-digit temperatures, a bright, sunny morning. This day, it was a 1-hour ride on an exercise bike in my basement. It is again a bright, sunny morning, but I was shielded from the winter old.

It felt good.

I've been riding an exercise bike daily since mid-November or so, working my way up from the 10-15 minute I rode occasionally in earlier therapy physical sessions first to 30 minutes, and now to 45 minutes at a time. Today for some reason, my mind said, just keep riding.

Over the last couple of months, I have begun exercising my knee more often and for longer, as I rehab from knee surgery last summer. In addition to the exercise bike, I have been walking a lot. Most days now, I walk 4-5 miles, usually in the evening with my family. It's not running, but it's moving, and it feels good to move -- and burn a few calories. After seven months of inactivity, I had gained twenty pounds and lost my lovely figure. I'm working on both those problems now.

The last two months of 2011 offered an experience that turned my memory inside out: my therapist had me run in our athletic department's Hydroworx pool. Put simply, this is a treadmill on the floor of a pool, which can be lowered to any level. Air jets blow water at the runner to create more resistance. Running in the water blunts impact on all the joints, including the knee, so my surgeon recommended it as part of my therapy.

The first time we speeded the treadmill from walk to gentle run, I was in ecstasy. My body fell into that comfortable rhythm that runners know and love. My heart raced. At first, my mind was empty, but soon it flooded with memories of runs past. I had not felt like a runner since last March. Yet there I was, a runner again.

That feeling was bittersweet, though. I knew that I could run in the pool only for a couple of months, as part of my therapy. Once my knee regained a certain level of strength and balance, pool sessions for therapy would end. And so they did. When I make my first Internet million, perhaps I'll build such a pool at my house, but for now I am back to walking and biking.

I haven't been writing about my knee, or about not running, for a lot of small reasons. This isn't a confessional blog, and I doubt many readers are interested in hearing me go on and on about my feelings. I also haven't find myself making connections between my rehab and my teaching or my software development, as I did when I was running. My experiences have been nothing unique, mostly what musical artist John Mellencamp calls "ditch digging": just doing what little I have to do each day. There is certainly something to be learned in this experience, but at this point I have nothing special to say.

Still, after riding for a full hour today, feeling a little like I did on all those Sunday long runs, reminded me of something worth remembering. When we do the little work day to day, we build something bigger. It takes patience. Another shovel of dirt.

Posted by Eugene Wallingford | Permalink | Categories: Personal, Running

September 01, 2011 4:09 PM

A Small Goodbye That Seems So Big

I just gave my older daughter a tearful final kiss and hug and left her in the care of the small liberal arts college that will be her home for most of the next four years. I have tried to prepare myself for this moment over the last year, weeks, and days. Nothing could have prepared me for how I feel at this moment.

College faculty and administrators like to speak these days about the "transformative experience" that college will be for their students. After all these years of my wife and I doing everything we knew how to help our daughter grow into the poised, creative, curious, engaging, delightful young woman she has become, it's hard for me to imagine how much more she can grow. Yet we know she will. As she returns to us on breaks and summer vacations (we hope!), I expect not to meet a new person, but the same Sarah we have come to know and respect and love all these years. She will surely know herself better than she does now, and that will open a new side of her to us.

I am eager to watch her become ever more who she is and who she wants to be. I am eager to get to know her more, again, and still. Her future excites me.

But at this moment, I hurt as only a father or mother can.

In her invocation at today's convocation, the college chaplain prayed that the students of the Class of 2015 find "clarity of purpose". I like that phrase. Clarity of purpose can serve as a capable foundation for all these students will do. In many ways, they begin their lives anew today.

But not every young person in that quad today is just a member of the Class of 2015. One of them is my daughter, with whom I have spent so much time for the last eighteen years, teaching her and being taught by her in turn. I have a hard time imagining what those years would have been like without her -- without her boundless energy, without her love of life and books and people, without her smile and hugs. Or without her patient tutelage of a young man who occasionally lacks clarity of purpose in some things but whose sense of duty to her has never wavered.


I love you, sweetie. You are ready to spread your wings and fly. I wish you every good thing in this world and beyond. But I'm not sure I'm ready to say good-bye just yet. I hope you can teach me that, and so much more.

Posted by Eugene Wallingford | Permalink | Categories: Personal

August 13, 2011 2:47 PM

Trust People, Not Technology

Another of the interviews I've read recently was The Rolling Stone's 1994 interview with Steve Jobs, when he was still at NeXT. This interview starts slowly but gets better as it goes on. The best parts are about people, not about technology. Consider this, on the source Jobs' optimism:

Do you still have as much faith in technology today as you did when you started out 20 years ago?

Oh, sure. It's not a faith in technology. It's faith in people.

Explain that.

Technology is nothing. What's important is that you have a faith in people, that they're basically good and smart, and if you give them tools, they'll do wonderful things with them. It's not the tools that you have faith in -- tools are just tools. They work, or they don't work. It's people you have faith in or not.

I think this is a basic attitude held by many CS teachers, about both technology and about the most important set of people we work with: students. Give them tools, and they will do wonderful things with them. Expose them to ideas -- intellectual tools -- and they will do wonderful things. This mentality drives me forward in much the same way as Jobs's optimism does about the people he wants to use Apple's tools.

I also think that this is an essential attitude when you work as part of a software development team. You can have all the cool build, test, development, and debugging tools money can buy, but in the end you are trusting people, not technology.

Then, on people from a different angle:

Are you uncomfortable with your status as a celebrity in Silicon Valley?

I think of it as my well-known twin brother. It's not me. Because otherwise, you go crazy. You read some negative article some idiot writes about you -- you just can't take it too personally. But then that teaches you not to take the really great ones too personally either. People like symbols, and they write about symbols.

I don't have to deal with celebrity status in Silicon Valley or anywhere else. I do get to read reviews of my work, though. Every three years, the faculty of my department evaluate my performance as part of the dean's review of my work and his decision to consider for me another term. I went through my second such review last winter. And, of course, frequent readers here have seen my comments on student assessments, which we do at the end of each semester. I wrote about assessments of my spring Intelligent Systems course back in May. Despite my twice annual therapy sessions in the form of blog entries, I have a pretty good handle on these reviews, both intellectually and emotionally. Yet there is something visceral about reading even one negative comment that never quite goes away. Guys like Jobs probably do there best not to read newspaper articles and unsolicited third-party evals.

I'll have to try the twin brother gambit next semester. My favorite lesson from Jobs's answer, though, is the second part: While you learn to steel yourself against bad reviews, you learn not to take the really great ones too personally, either. Outliers is outliers. As Kipling said, all people should count with you, but none too much. The key in these evaluations to gather information and use it to improve your performance. And that most always comes out of the middle of the curve. Treating raves and rants alike with equanimity keeps you humble and sane.

Ultimately, I think one's stance toward what others say comes back to the critical element in the first passage from Jobs: trust. If you trust people, then you can train yourself to accept reviews as a source of valuable information. If you don't, then the best you can do is ignore the feedback you receive; the worst is that you'll damage your psyche every time you read them. I'm fortunate to work in a department where I can trust. And, like Jobs, I have a surprising faith in my students' fairness and honesty. It took a few years to develop that trust and, once I did, teaching came to feel much safer.

Posted by Eugene Wallingford | Permalink | Categories: Managing and Leading, Personal, Software Development, Teaching and Learning

July 29, 2011 8:56 PM

A Teacher Learns from Coaches -- Run to the Roar

A Teacher Learns from Coaches -- Run to the Roar

For what is genius, I ask you,
but the capacity to be obsessed?

Gustav Detter, a 2009 Trinity College squash player

One thing about recovering from knee surgery: it gives you lots of time to read. In between bouts of pain, therapy, and sleep, I have been reading newspapers, magazines, and a few books lying around the house, including the rest of a Dave Barry book and the excellent but flawed law school memoir One L. Right now I am enjoying immensely re-reading Isaac Asimov's Foundation trilogy. (Psychohistory -- what a great computational challenge!)

The most unusual book I've read thus far has been Run to the Roar. This is not great literature, but it is an enjoyable read. It draws its power to attract readers from perhaps the most remarkable sports streak in history at any level: the men's squash team at Trinity College has won thirteen consecutive national titles and has not lost a single match during the streak. The thread that ties the book together as a story is the tale of the eleventh national championship match, in 2009 against Princeton University. This match is considered by many to be the greatest collegiate squash match of all time, won 5-4 by Trinity in see-saw fashion. Six of the nine matches went the full five games, with three of those requiring comebacks from 0-2 down, and only one match ended in straights. Two great teams, eighteen great players, battling to the last point. In the end, Trinity survived as much as it won.

I didn't know much about squash before the match, though I used to play a little racquetball. Fortunately, the book told me enough about the game and its history that I could begin to appreciate the drama of the match and the impressive nature of the streak. Unbelievable story, really.

But the book is also about its co-author, Trinity coach Paul Assaiante, both his life and his coaching methods. The book's subtitle is "Coaching to Overcome Fear", which captures in one phrase Assaiante's approach as well as any could. He works to help his players play in the moment, with no thoughts of external concerns weighing on their minds; enjoying the game they love and the privilege they have to test their preparation and efforts on the court in battle.

Assaiante views himself as a teacher, which makes what he says and the way he says it interesting to the teacher in me. There were many passages that struck a chord with me, whether as an "I have that pattern" moment or as an idea that I might try in my classroom. In the end, I saved two passages for more thought.

The first is the passage that leads off this entry. Assaiante attributed it to Steven Millhauser. I had never heard the quote, so I googled it. I learned that Millhauser is an award-winning author. Most hits took me pages with the quote as the start of a longer passage:

For what is genius, I ask you, but the capacity to be obsessed? Every normal child has that capacity; we have all been geniuses, you and I; but sooner or later it is beaten out of us, the glory fades, and by the age of seven most of us are nothing but wretched little adults.

What a marvelous pair of sentences. It's easy to see why the sentiment means so much to Assaiante. His players are obsessive in their training and their playing. Their coach is obsessive in his preparation and his coaching. (The subtitle of one of the better on-line articles about Trinity's streak begins "Led by an obsessive coach...".)

My favorite story of his coaching obsessiveness was how he strives to make each practice different -- different lengths, different drills, different times of day, different level of intensity, and so on. He talks of spending hours to get each practice ready for the team, ready to achieve a specific goal in the course of a season aimed at the national championship.

Indeed, Assaiante is seemingly obsessive in all parts of his life; the book relates how he conquered several personal and coaching challenges through prolonged, intense efforts to learn and master new domains. One of the sad side stories of Run to the Roar explores whether Assaiante's obsessiveness with coaching squash contributed to the considerable personal problems plaguing his oldest child.

Most really good programmers are obsessive, too -- the positive compulsive, almost uncontrollable drive that sticks with a thorny problem until it is solved, that tracks a pernicious bug until it is squashed. Programming rewards that sort of single-mindedness, elevating it to desirable status.

I see that drive in students. Some have survived the adults and schools that seem almost aimed at killing children's curiosity and obsessiveness. My very best students have maintained their curiosity and obsessiveness and channeled them positively into creative careers and vocations.

The best teachers are obsessive, too. The colleagues I admire most for their ability to lead young minds are some of the most obsessive people I know. They, too, seem to have channeled their obsessiveness well, enabling them to lead well-adjusted lives with happy, well-adjusted spouses and children -- even as they spend hours poring over new APIs, designing and solving new assignments for their students, and studying student code to find the key thing missing from their lectures, and then making those lectures better.

(As an aside, the Millhauser quote comes from his novel, "Edwin Mullhouse: The Life and Death of an American Writer 1943-1954 by Jeffrey Cartwright", a book purportedly written by a seven-year-old. I read a couple of reviews such as this one, and I'm not sure whether I'll give it a read or not. I am certainly intrigued.)

The second passage I saved from Assaiante's book comes from Jack Barnaby, Harvard's legendary squash and tennis coach:

The greatest limitation found in teachers is a tendency for them to teach the game the way they play it. This should be avoided. A new player may be quite differently gifted, and the teacher's personal game may be in many ways inappropriate to the pupil's talents. A good teacher assesses the mental and physical gifts of his pupil and tries to adapt to them. There is no one best way to play the game.

(I think this comes from Barnaby's out-of-print Winning Squash Racquets, but I haven't confirmed it.)

One of the hardest lessons for me to learn as a young teacher was not to expect every student to think, design, or code like me. For years I struggled and probably slowed a lot of my students' learning, as they either failed to adapt to my approach or fought me. Ironically, the ones most likely to succeed in spite of me were the obsessive ones, who managed to figure things out on their own by sheer effort!

Eventually I realized that being more flexible wasn't dumbing down my course but recognizing what Barnaby knew: students may have their own abilities and skills that are quite different from mine. My job is to help them maximize their abilities as best I can, not make them imitate me. Sometimes that means helping them to change, perhaps helping them recognize the need to change, but never simply to force them into the cookie cutter of what works well for me.

Sometimes I envy coaches, who usually work with a small cadre of student-athletes for an entire year, with most or all of them studying under the coach for four years. This gives the coach time to "assess the mental and physical gifts of his pupils and try to adapt to them". I teach courses that range from 10 to 40 students in size, two a year, and my colleagues teach six sections a year. We are lucky to see some students show up multiple times over the course of their time at the university, but it is with only a select few that I have the time and energy to work with individually at that level. I so try to assess the collective gifts, interests, and abilities of each class and adapt how and what I teach them as best as I am able.

In the end, I enjoyed all the threads running through Run to the Roar. I'm still intrigued by the central lesson of learning to "run to the roar", to confront our fears and see how feeble what we fear often turns out to be. I think that a lot of college students are driven by fear more than we realize -- by fear of failing in a tough major, fear of disappointing their parents, fear of not understanding, or appearing unintelligent, or not finding a career that will fulfill and sustain them. I have encountered a few students over the years in whom I came to see the fear holding them back, and on at least some occasions was able to help them face those fears more courageously, or at least I hope so.

Having read this book, I hope this fall to be more sensitive to this potential obstacle to learning and enjoyment in my class, and to be more adaptable in trying to get over, through, or around it.

Posted by Eugene Wallingford | Permalink | Categories: Personal, Teaching and Learning

July 28, 2011 9:20 PM

Cautiously Optimistic

the equipment for a makoplasty

After two bouts of bad news about my knee -- first the diagnosis and then the ineffectiveness of simpler fixes -- I have received good news, all things considered. A week ago Monday, I underwent a relatively new form of partial knee replacement called makoplasty. The surgeon thought the operation went very well. Good news at last!

Now I am in a second round of recovery and rehabilitation, with therapy much like the first round: lots of non-weight-bearing motion to loosen the joint and to strengthen the muscles in the joint and the rest of the leg. There is certainly more pain than last time, but it's not so bad. I did have an adverse reaction to the medication prescribed for the pain, which has been uncomfortable and slowed my recovery, but I think I have to be happy with where I am and cautiously optimistic about where I can be in a few weeks and months. While that still almost certainly still will not include running, I should be able to return to an active life.

An experience from the surgery reminded me that, while I may be able to become active again, I won't be a youngster anymore. This procedure required spending one night in the hospital, so that they could monitor my vitals and my incision closely for a few hours. On the overnight shift, I had a college-aged nurse's aide who helped me several times. She called me, "Honey". Twice. Each time, I felt twice my age, rather than twice hers.

Still, I look forward to the progress a little hard work can provide to feeling young again.

Posted by Eugene Wallingford | Permalink | Categories: Personal, Running

July 01, 2011 2:29 PM

What Would Have To Be True...

Yesterday, I read Esther Derby's recent post, Promoting Double Loop Learning in Retrospectives, which discusses ways to improve the value of our project retrospectives. Many people who don't do project retrospectives will still find Derby's article useful, because it's really about examining how we think and expanding possibilities.

One of the questions she uses to jump start deeper reflection is:

What would have to be true for [a particular practice] to work?

This is indeed a good question to ask when we are trying to make qualitative changes in our workplaces and organizations, for the reasons Derby explains. But it is also useful more generally as a communication tool.

I have a bad personal habit. When someone says something that doesn't immediately make sense to me, my first thought is sometimes, "That doesn't make sense." (Notice the two words I dropped...) Even worse, I sometimes say it out loud. That doesn't usually go over very well with the person I'm talking to.

Sometime back in the '90s, I read in a book about personal communication about a technique for overcoming this disrespectful tendency, which reflects a default attitude. The technique is to train yourself to think a different first thought:

What would have to be true in order for that statement to be true?

Rather than assume that what the person says is false, assume that it is true and figure out how it could be true. This accords my partner the respect he or she deserves and causes me to think about the world outside my own point of view. What I found in practice, whether with my wife or with a professional colleague, was that what they had said was true -- from their perspective. Sometimes we were starting from different sets of assumptions. Sometimes we perceived the world differently. Sometimes I was wrong! By pausing before reacting and going on the defensive (or, worse, the offensive), I found that I was saving myself from looking silly, rash, or mean.

And yes, sometimes, my partner was wrong. But now my focus was not on proving his wrong but on addressing the underlying cause of his misconception. That led to a very different sort of conversation.

So, this technique is not an exercise in fantasy. It is an exercise in more accurate perception. Sometimes, what would have to be true in the world actually is true. I just hadn't noticed. In other cases, what would have to be true in the world is how the other person perceives the world. This is an immensely useful thing to know, and it helps me to respond both more respectfully and more effectively. Rather than try to prove the statement false in some clinical way, I am better served by taking one of two paths:

  • helping the other person perceive the world more clearly, when his or her perception clashes with reality, or
  • recognizing that the world is more complicated than I first thought and that, at least for now, I am better served by acting from a state of contingency, in a world of differ possible truths.

I am still not very good at this, and occasionally I slip back into old habits. But the technique has helped me to be a better husband as well as a better colleague, department head, and teacher.

Speaking as a teacher: It is simply mazing how different interactions with students can be when, after students say something that seems to indicate they just don't get it, "What would have to be true in order for that statement to be true?" I have learned a lot about student misconceptions and about the inaccuracy of the signals I send students in my lectures and conversations just by stepping back and thinking, "What would have to be true..."

Sometimes, our imaginations are too small for our own good, and we need a little boost to see the world as it really is. This technique gives us one.

Posted by Eugene Wallingford | Permalink | Categories: General, Personal, Teaching and Learning

June 17, 2011 12:28 PM

Failure and the Liberal Arts

Many people are talking about Conan O'Brien's recent commencement address at Dartmouth, in which he delivered vintage Conan stand-up for fifteen minutes and a thoughtful, encouraging, and wise message about failure. We talk about the virtues of failure in many contexts, including start-ups, agile software development, and learning. O'Brien reminds us that failure hurts. It makes us question our dreams and ourselves. But out of the loss can come conviction, creation, and re-creation. Indeed, it is in failing to achieve the ideals we set for ourselves that ends up making us who we are. Your dream will change. That's okay.

If you haven't seen this speech, check it out. It really is quite good, both entertaining and educational. If you are not particularly a fan of O'Brien's stand-up, you can skip to 15:40 or even 16:15 to get to the important message at its heart.

I've been thinking about failure and liberal arts colleges in New England in recent days, as my daughter prepares to head off for the latter with a little fear of the former. So this talk meant a lot to me. She isn't sure yet what she wants to major in or do for a living. This has been tough, because she has felt subtle pressure from a lot of people that she should have a big dream, or at least have a specific goal to work toward. But she likes so many things and isn't ready to specialize yet.

So she went looking for a liberal arts college. Then she hears a lot about unemployed English grads, students who lack practical job skills, and 20-somethings with crushing loan debts and no prospect of paying them off. That's where the fear comes in...

But I think people are making a fallacious connection between undergraduate education and professional prospects. First of all, a student can go to school with a particular job path in mind, amass huge debt, and enter a profession that doesn't pay well enough to pay it off. I saw news articles in the last year that talked about problems some grads have faced with degrees in social work and counseling psychology. There is nothing wrong with these degrees per se, but the combination of low median pay and debt amassed even at public schools can be deadly.

Second, and perhaps more important, many people seem to misunderstand the nature of a liberal education. They think it means studying only "soft" academic disciplines in the humanities, such as literature, history, and philosophy. Maybe that is what most people mean by the term, but I think about it more broadly as the freedom to read and study widely. Liberal arts majors are not limited to studying only in the humanities. They can study literature and also economics, chemistry, and international relations. They can study languages and also political science and a little math; history and also graphic design. They could even learn a little computer programming.

The sciences are part of a liberal education. I think CS can be, too. And the small size of many liberal arts majors gives students the freedom to sample broadly across the spectrum of human knowledge and skills.

The danger of a liberal arts education is that some students and professors take it as license to study only in the humanities. But the ultimate value of a liberal arts education lies not in that narrow circle, as valuable and rewarding as it can be in its own right. The value lies in intersections: the ability to understand them, the ability to recognize them, and the ability to work in them. It is most desirable to learn something about a lot of different things, even real problems and real solutions in the modern world. Put together with a few key skills, the combination is powerful.

Just as it's important not to be too narrowly trained, it's important not to be too narrowly "liberally educated".

So I've encouraged my daughter not to worry about her lack of narrow focus just yet. She has a lot to learn yet, most importantly about the challenging problems that will vex humanity in the coming century. Many of them lie at the intersection of several disciplines, and solving them will be the responsibility of well-prepared minds.

Posted by Eugene Wallingford | Permalink | Categories: Personal, Teaching and Learning

June 08, 2011 7:24 PM

From PDF Files to Sense of Loss

After I wrote my previous post, I downloaded the PDF version of the June issue of Chess Life to check out its quality and readability. Lo and behold, the first letter to the editor said:

I would like to seek readers' help in solving my dilemma about Chess Life magazine. Since 1972 -- almost 40 years! -- I have saved every copy of Chess Life. I treasure these magazines, of course, and I want to keep the "streak" going until I pass away. However, I also recognize that mailing magazines is costly for USCF, and that it is much less "green" than reading Chess Life online.

So, dear readers, what should I do? Keep the 40-year streak going despite the cost and environmental impact, or get with the times and read Chess Life online?

The motive force behind my dilemma is less base than wanting to maintain a streak, and yet more selfish than wanting to save the earth. Still, I chuckled at the unexpected conjunction served up by the universe.

While writing that post, I read back over the much older post I linked to, Electronic Communities and Dancing Animals. It contains an extended passage that I reread and thought about for a while:

I know this beauty, and I'm sure you do. We are physical beings. The ability and desire to make and share ideas distinguish us from the rest of the world, but still we are dancing animals. There seems in us an innate need to do, not just think, to move and see and touch and smell and hear. Perhaps this innate trait is why I love to run.

But I am also aware that some folks can't run, or for whatever reason cannot sense our physical world in the same way. Yet many who can't still try to go out and do. At my marathon last weekend, I saw men who had lost use of their legs -- or lost their legs altogether -- making their way over 26.2 tough miles in wheelchairs. The long uphill stretches at the beginning of the course made their success seem impossible, because every time they released their wheels to grab for the next pull forward they lost a little ground. Yet they persevered. These runners' desire to achieve in the face of challenge made my own difficulties seem small.

I suspect that these runners' desire to complete the marathon had as much to do with a sense of loss as with their innate nature as physical beings. And I think that this accounts for Vonnegut's and others' sentiment about the insufficiency of electronic communities: a sense of loss as they watch the world around evolve quickly into something very different from the world in which they grew.

Living in the physical world is clearly an important part of being human. But it seems to be neither necessary nor sufficient as a condition.

Another timely conjunction. I am heartened now by the stout spirit of the runners I saw in DC. I am also reminded anew of how small my own loss is when compared to theirs, and how much more noble its source. Fortunately, I seem to have reached a state of acceptance relatively quickly, enough so that I don't feel much envy or sadness when I see runners pass by my house on the bike trail that leads to many of my favorite routes. Still, at heart, I am a dancing animal.

Posted by Eugene Wallingford | Permalink | Categories: Personal, Running

June 06, 2011 9:12 PM

Magazines, PDF Files, and a Lifetime of Memories

I remember the day I received my first issue of Chess Life & Review magazine. It was the summer of 1979, in late June or early July. I had won a membership in the U.S. Chess Federation as part of a local goodwill tournament, by virtue of beating my good buddy and only competition for the junior prize. My victory entitled me to the membership as $20 of loot, which includes a portable set I use to this day and a notation book that records my games over a period of five or ten years.

Play it again, Sam.

That first issue arrived while I was at summer school. The cover heralded the upcoming U.S. Open championship, but inside the story of Montreal 1979, a super-GM tournament, captivated me with the games of familiar names (Karpov, Tal, Larsen, and Spassky) and new heroes (Portisch, Huuml;bner, Hort, and Ljubojevic). A feature article reviewed films of the 1940s that featured chess and introduced me to Humphrey Bogart's love of and skill at the game I loved to play. Bogart: the man's man, the tough-guy leading man at whose feet women swooned. Bogart! The authors of the magazine's regular columns became my fast friends, and for years thereafter I looked forward monthly to Andy Soltis's fun little stories, which always seemed to teach me something, and Larry Evans's Q-n-A column, which always seemed to entertain.

I was smitten, as perhaps only a young bookish kid can be.

Though I haven't played tournament chess regularly in three decades, I have remained an occasional player, a passionate programmer, and a lovestruck fan. And I've maintained my membership in the USCF, which entitles me to a monthly issue of Chess Life. Though life as husband, father, and professor leave me little time for the game I once played so much, every month I anticipate the arrival of my new issue, replete with new names and new games, tournament reports and feature articles, and regular columns that include Andy Soltis's "Chess to Enjoy". Hurray!

... which is all prelude to my current dilemma, a psychological condition that reveals me a man of my time and not a man of the future, or even the present. It's time to renew my USCF membership, and I am torn: do I opt for the membership that provides on-line access only to Chess Life?

For the last few years, ever since we moved into a new house and I cam face to face with just how much stuff I have, I've been in the process of cutting back. Even before then, I have made some society membership choices based in part on how little I need more piles of paper taking up space in my house and attention in my mind. This is the 21st century, right? I am a computer scientist, who deals daily in digital materials, who has disk space beyond his wildest dreams, whose students have effortlessly grown into a digital world that makes magazines seem like quaint compendia of the past. Right?

Yet I waffle. I can save roughly $7 a year by going paperless, which is a trifle, I know, but a prudent choice nonetheless. Right?

Undoubtedly, my CL&R-turned-CL collection takes up space. If I stem the tide of incoming issues, I can circumscribe the space needed to store my archive and devote future space to more worthy application. Perhaps I could even convert some of the archive into digital form and recoup space already spent?

This move would space, but if I am honest it does not free up all my attention. My magazines will join my music collection in the river of bits flowing into my future, being copied along from storage device to storage device, from medium to medium, and from software application to software application. I've lived through several generations of storage media, beginning in earnest with 5-1/4" floppies, and I'm sure I'll live through several more.

And what of changing formats? The text files that have followed me from college remain readable, for the most part, but not everything survives. For every few files I've converted from WordPerfect for DOS I have surely lost a file or two. Occasionally I run across one and ask myself, is it worth my time to try to open it and convert it to something more modern? I am sad to say that too often the answer is, well, no. This never happens to my books and magazines and pamphlets from that time. I choose to keep or to discard, and if I have it, I can read it. Where will PDF be in 50 years?

the cover of Bobby Fischer's 'My 60 Memorable Games'

I am also just old enough that I somewhat cherish having a life that is separate from my digital existence. When I have the chance to play chess these days, I still prefer to pull out a board and set up the pieces. The feel of the ivory or plastic or wood in my hands is part of the experience -- not essential to the experience, I suppose, in a cosmic sense, but a huge ingredient to my personal experience. I have been playing chess on computers since 1980 or so, which isn't much later than I began playing the game in earnest as in grade school, so I know that feeling, too. But feeling the pieces in my hand, poring over My 60 Memorable Games (another lifelong treasure from the booty that first brought me Chess Life) line by line in search of Bobby Fischer's magic... these are a part of the game for me.

Ultimately, that's where my renewal dilemma lies, too. My memories of checking the mailbox every day at that time of the month, eager to find the next issue of the magazine. The smell of the ink as I thumbed through the pages, peeking ahead at the delights that awaited me. The feel of the pages as I turned to the next column or article or advertisement. The joy of picking out an old issue, grabbing that magnetic portable set from 30-odd years ago, and settling into a comfortable chair for an evening of reminiscence and future-making. All are a part of what chess has been for me. A cache of PDF files, $22 over three years, and a little closet space hardly seem sufficient consideration.

Alas, we are all creatures of our own times, I no less than any man. Even though I know better, I find myself pulled backward in time just as much as Kurt Vonnegut, who occasionally waxed poetic about the future of printed book. Both Vonnegut and I realize that the future may well exceed our imaginations, but our presents retain the gifts of days past.

Posted by Eugene Wallingford | Permalink | Categories: Computing, Personal

June 03, 2011 1:46 PM

A Second Round of Surprise

When we last visited this tale, I had learned that my right knee suffers from a condition known as OCD and that my life as a distance runner was likely over. Depending on the size of the lesion and the state of the bone tissue, there are several potential reparative and restorative procedures that my surgeon could take. But running was almost certainly out of question.

After doing some research, we decided to do arthroscopic surgery to try to repair the lesion. My surgeon hoped that he would be able to do microfracture surgery or, if the lesion were a little bigger, perhaps the OATS procedure, which transplants good cartilage to the lesion for regrowth. If the lesion were too large for either of these procedures, there was one more option, the first step of a newer technique known as CARTICEL. The expected procedures, microfracture or OATS, would require a recovery period of six to eight weeks, during which I would not be allowed to put weight on the knee but would be doing a lot of motion therapy to stimulate blood flow and tissue growth.

I went in for arthroscopy last Wednesday, May 25. It had been thirty years since I had undergone surgery, to repair the rotator cuff in my left shoulder, and this experience was quite different. Medical technology has come a long way in thirty years. We did the operation at an outpatient surgery center, which was much more comfortable than the typical hospital. I was in and out in about four hours, despite being placed under general anesthesia. I went to sleep and woke up comfortably and even recall some of the conversations I had with nurses as I left the post-op room. The surgeon spoke to my wife after surgery, but I was still out cold. That evening, I was home resting comfortably.

The surgery was one of those good news/bad news things. The good news was that my recovery would be faster than we had planned. The bad news was why: the surgeon was not able to do either microfracture or OATS, because the damage to my joint is more extensive than we thought. It looks to be more degenerative than the result of a specific trauma, which fits how it presented better than the typical cases. So, instead he removed some loose cartilage, including one large piece, and cleaned up cartilage on both sides of the joint.

For the last week, I have been doing physical therapy, using lots of non-weight-bearing motion to loosen the joint and to strengthen other muscles in the leg, so that they can take pressure off the knee when we return it to full use.

Yesterday I went in for my post-op appointment with the surgeon, to gauge the state of recovery and to discuss next steps. He showed me pictures of the inside of my knee from the scope and explained why he could not do the procedures he had planned. The reasons came down to two. First, the lesion is wider and deeper than we had hoped, and microfracture and OATS only work on shallow wounds of a few centimeters at most. Second, there is also damage on the tibia across from the lesion on the femur. This is known as a "kissing lesion" and means that any new tissue growth at the bad spot on the femur would be damaged whenever I walked and the knee joint closed.

The next thing for us to try is a partial knee replacement, in which he cleans up the damaged area and fills the lesion with a piece of something. Basically, the options are again two. One is called osteochondral allograft, which uses a bone and tissue plug taken from a cadaver. The second is to use a synthetic implant made of the plastic and metal. The surgeon suggested that I may be a candidate for makoplasty, which uses computer visualization to help create the implant and an interactive robotic arm and to place it in the lesion and attach it to the femur. That sounds incredibly cool. I have to be sure not to let my fascination with the technology unduly influence my decision!

At this point, my wife and I have some research to do, to decide what, if anything, we want to do next. I am on the young side for even a partial knee replacement, but medical advances are improving the longevity of the procedures' effectiveness. My surgeon is sensitive to the fact that, as a relatively long guy, I probably want to live a more active lifestyle than an unrepaired joint is likely to allow. It is a big step for me, whatever we choose.

In any case, the surgeon says I need to continue working diligently on physical therapy, to build up the muscles both in the knee and, more importantly, all the other muscles and joints in the leg. If I don't do more surgery, these muscles are essential to supporting the damaged knee; if I do opt for more surgery, these muscles need to be as strong as possible to support the knee during recovery and rehabilitation. So, off to therapy I go.

If any of my running friends are still reading, I can add this: given both the size and character of my lesion and the way it presented, the surgeon is unable to say to what extent my heavy mileage affected the condition. Clearly, heavy mileage delivers a lot of repeated trauma to our knee joints. But with no previous pain or disruption to my running, it seems almost as likely that my running delayed the onset of the bone necrosis as that it caused it. I seem simply to have been unlucky genetically in this one regard.

Posted by Eugene Wallingford | Permalink | Categories: Personal, Running

May 24, 2011 12:38 PM

Difficult Students, Difficult Professors, Difficult Relationships

We professors usually write glowingly of our students. Writing bad things about students in public seems like a bad idea. Besides, we mean the good things we say. By and large students are great people to be around. We get to learn with them watch them grow. Yet...

Yesterday, I tweeted out of an emotion I occasionally feel when I read my student evaluations after a semester ends: even if n-1 students say positive things and offer constructive suggestions for improvement, my mind focuses on the one student who was unhappy and complained unhelpfully. It's just the ego at work; objectively, every instructor realizes that whenever a bunch of students gather in one place, it is likely that a few will be unhappy. It's unrealistic -- foolish, really -- to think that everyone should like you.

Fortunately, after a few minutes (or hours, or days, if you haven't yet trained your mind in this discipline yet), the feeling passes and you move forward, learning from the assessment and improving the course.

Occasionally, the negative comments are not a random event. In this case, I'm pretty sure I know who was unhappy. This student had felt similarly in previous semesters. He or she is just not a fan of mine.

If we are all honest with ourselves and each other, we have to admit that the same is true for us professors. Occasionally, we encounter a student who rubs us the wrong way. It is rare, perhaps surprisingly so, but every few years I encounter a student of whom I am not a big fan. Sometimes the feeling is mutual, but not always. Occasionally, I have students who don't like me much but whom I like well enough, or students who rub me the wrong way but seem to like me fine. The good news is that, even in these circumstances, students and professors alike do a pretty good of working together professionally. For me, it's a point of professional pride not to let how I feel about any student, positive or negative, affect my courses.

I almost titled this post "Difficult Students", but that struck me as wrong. From the student's perspective, this is about difficult instructors. And it's not really about students and instructors at all, at least most of the time. Other students enjoy my courses even when one does not; other faculty like and enjoy the students who aren't my favorites. It's about relationships, one-on-one.

And, as I wrote in the George Costanza post linked above, this is to be expected. We are all human.


In response to my tweet, David Humphrey shared this comic to help ease the psychological trauma of even one negative student:

Haters gonna hate

(If you prefer an analgesic with a harder edge, I offer you Gaping Void's take on the matter.)

Posted by Eugene Wallingford | Permalink | Categories: Personal, Teaching and Learning

May 23, 2011 2:34 PM

Plan A Versus Plan B

Late last week, Michael Nielsen tweeted:

"The most successful people are those who are good at Plan B." -- James Yorke

This is one of my personal challenges. I am a pretty good Plan A person. Historically, though, I am a mediocre Plan B person. This is true of creating Plan B, but more importantly of recognizing and accepting the need for Plan B.

Great athletes are good at Plan B. My favorite Plan B from the sporting world was executed by Muhammad Ali in the Rumble in the Jungle, his heavyweight title fight against George Foreman in October 1974. Ali was regarded by most at that time as the best boxer in the world, but in Foreman he encountered a puncher of immense power. At the end of Round 1, Ali realized that his initial plan of attacking Foreman was unlikely to succeed, because Foreman was also a quick fighter who had begun to figure out Ali's moves. So Ali changed plans, taking on greater short-term risk by allowing Foreman to hit him as much as he wanted, so long as the blows were not the kind likely to end the fight immediately. Over the next few rounds, Foreman began to wear down, unaccustomed to throwing so many punches for so many rounds against an opponent who did not weaken. Eventually, Ali found his opening, attacked, and ended the fight in Round 8.

This fight is burned in my mind for the all-time great Plan B moment: Ali sitting on his stool between the first and second rounds, eyes as wide and white as platters. I do not ever recall seeing fear in Muhammad Ali's eyes at any other time in his career, before or after this fight. He believed that Foreman could knock him out. But rather than succumb to the fear, he gathered himself, recalculated, and fought a different fight. Plan B. The Greatest indeed.

Crazy software developer that I am, I see seeds of Plan B thinking in agile approaches. Keep Plan A simple, so that you don't overcommit. Accept Plan B as a matter of course, refactoring in each cycle to build what you learn from writing the code back into the program. React to your pair's ideas and to changes in the requirements with aplomb.

There is good news: We can learn how to be better at Plan B. It takes effort and discipline, just as changing any of our habits does. For me, it is worth the effort.


If you would like to learn more about the Rumble in the Jungle, I strongly recommend the documentary film When We Were Kings, which tells the story of this fight and how it came to be. Excellent sport. excellent art, and you can see Ali's Plan B moment with your own eyes.

Posted by Eugene Wallingford | Permalink | Categories: General, Personal, Software Development

May 05, 2011 3:35 PM

Reaching for Too Much, in Life and Software Development

I just read this passage from The Rhythm of Life, by Matthew Kelly:

You never can get enough of what you don't really need.

Fulfillment comes not from having more and more of everything forever into oblivion. Fulfillment comes from having what you need.

Kelly is talking about how we live our lives. However, I could not help but think of You Aren't Gonna Need It and agile software development.

From there, Kelly takes a moral turn, but even then I hear the agile voice within:

The whole world is chasing illegitimate wants with reckless abandon. We use all of our time, effort, and energy in the pursuit of our illegitimate wants, hypnotized by the lie that our illegitimate wants are the key to our happiness.

At the same time, the gentle voice within us is constantly calling out to us, trying to encourage us not to ignore the wisdom we already possess.

There is a lot to be said for learning to be content with implementing the features we are working on right now, not features we think are coming in the future. Perhaps if we can learn to be content in life we can also learn to be content in code.

Posted by Eugene Wallingford | Permalink | Categories: Personal, Software Development

May 04, 2011 5:39 AM

Mission Statements and Implementation Details

Last week, I thought out loud about the university's relationship with its students, which may be different from what some are thinking it is. I just ran across an interview with Tim O'Reilly from last week about the future of his industry. His industry is different from what some are thinking it is, too:

At O'Reilly the way we think about our business is that we're not a publisher; we're not a conference producer; we're a company that helps change the world by spreading the knowledge of innovators.

My university could do worse than simply stealing O'Reilly's mission statement. There is more to our mission, of course. Research universities, at least, have historically also been about creating knowledge; universities such as mine have been as much about integrating knowledge as creating it. Public universities also serve their states in various ways, not the least of which is preparing educated citizens for participation in public life. It's hard to serve all these roles, and ultimately it all comes down to students and learning.

Mission statements and strategic plans have a bad reputation among faculty, and for good reason. They to be corporate statements diluted, by trying to say everything and, as a result, saying nothing much. But thinking hard about the real core of the university's mission might help us evolve and survive, rather than becoming the next dinosaur.

Our mission certainly isn't about classrooms, packaged courses, and labs filled with general purpose computers. Those are implementation details, built from the technology of a particular era. Just as the book and newspaper are undergoing changes in their basic form as technology evolves, so too should the university experience. Some of the technology we use now belongs to a dying era.

That's what makes the O'Reilly's statement I quote above so important. He has always recognized that his business is not defined by the technology of the time. Some people are afraid of changing technology because they do see themselves and their businesses as defined by their implementations. As technology evolves, O'Reilly is comfortable evolving his business model along with it, without abandoning what the company is really about.

Posted by Eugene Wallingford | Permalink | Categories: Personal

May 03, 2011 4:26 PM

There Is No Normal

Part of what made diagnosing my knee injury challenging is that the injury has not presented normally. Normally, this condition follows an obvious trauma. I did not suffer one. Normally, the symptoms include occasional locking of the joint and occasionally feeling as if the joint is going to give out. I have not experienced either. Normally, there is more pain than I seem to be having.

The doctors were surprised by this unusual presentation, but it didn't worry them much. They are used to the fact that there is no normal.

The human body is a complex machine, and people subject their bodies to a complex set of stimuli and conditions. As a result, the body responds in an unbelievable number of ways. What we think of as the "normal" path of most diseases, injuries, and processes is a composite of many examples. Each symptom or observation has some likelihood of occurring, but it is common for a particular case to look quite unusual.

This is something we learn when we study statistical methods. It's possible that no number in a set is equal to the average of all the numbers in a set. It's possible that no member in a set is normal in the sense of sharing all the features that are common to most members.

A large software system is a complex machine, and people subject software to a complex set of stimuli and conditions. As a result, the software responds in a surprising number of ways. When we think of this from the perspective people as users, we realize just how important designing for usability, reliability, and robustness are.

Programmers are people who interact with software, too, and we subject our programs to a wide-ranging set of demands. When we think about "there is no normal" from this perspective, we better understand why it is so challenging to debug, extend, and maintain programs.

Our programs may not be as complex as the human body, and we try to design them rather than let them evolve unguided. But I think it's still useful to program with a mindset that there is no normal. That way, like my doctor, we can handle cases that seem unusual with aplomb.

Posted by Eugene Wallingford | Permalink | Categories: Personal, Software Development

April 30, 2011 10:05 AM

A Shock to the System

I received some bad news from the doctor yesterday. It looks like my running career is over.

As I wrote earlier this month, I haven't run since March 4, when I came down with the flu. As that was ending, my right knee started to hurt and swell, though I was not aware of any injury or trauma that might have caused the symptoms.

In the few weeks since that entry, the pain and swelling have decreased but not disappeared. We finally had an MRI done on Thursday so that an orthopedic surgeon could examine me yesterday.

The diagnosis: Osteochondritis dissecans (OCD). This is a condition in which articular cartilage in a joint and the bone to which it attaches crack or pull away from the rest of the bone. OCD occurs when the subchondral bone is deprived of blood. As near as I can tell from my reading thus far, the cause of the blood deprivation itself is less well understood.

Depending on the size of the lesion and the state of the bone tissue, there are several potential reparative and restorative steps that my surgeon can take. Unfortunately, even with the best outcomes, the new tissue is more fragile than the original tissue and usually is not able to withstand high-impact activity over a long period.

That's where we get to the bad news. I almost surely cannot run any more.

After the doctor told me his diagnosis and showed me the MRI, he said, "You're taking this awfully well." To be honest, as the doctor and I talked about this, it felt as if we were discussing someone else. I'm not the sort of person who tends to show a lot of emotion in such situations anyway, but in this case the source of my dispassion was easy enough to see. In an instant, I was jolted from trying to get better to never getting better. On top of that jolt, it wasn't all that long ago that I went from running 30+ peaceful miles a week to not running at all. I was stunned.

On the walk back to my office, my conscious and subconscious minds began to process the news, trying to make sense of it. I have had a lot of thoughts since then. My first was that there was still a small chance that the lesion wouldn't look so bad under the scope, that it could heal and that I would be back on the road soon. I chuckled when I realized that I had already entered the stage of grief, denial. That small chance does exist, but it is not a rational one on which to plan my future. The expected value of this condition is much closer to long-term problems with the knee than to "yeah, I'm running again". I chuckled because my mind was so predictable.

Not being able to run is a serious lifestyle change for someone who has run 13,000 miles in the last eight years. It also means that I will have to make other changes to my lifestyle as well. My modest hope is that eventually I will still be able to take walks with my wife. In then grand scheme, I would probably miss those more than I miss the running.

I'm also going to have to change my diet. As a runner, I have been able to consume a lot of calories, and it will be impossible to burn that many calories without running or other high-impact exercise. This may actually be a good thing for my health, as strange as that may sound. Burning 4000 extra calories a week covers up a multitude of eating sins. I'll have to do the right thing now. Maybe this is what people mean when they see a misfortune as an opportunity?

I've had only two really sad thoughts since hearing the news. First, I wish I had know that my last run was going to be my last run. Perhaps I could have savored it a bit more. As it is, it's already receding into the fogginess of my memory. Second, I wonder what this will mean for my sense of identity. For the last decade, I have been a runner. Being a runner was part of who I was. That is probably gone now.

Of course, when I put this into context, it's not all that bad. There could have been much worse diagnoses with much more dire consequences for my future. Much worse events could have happened to me or a loved one. As one of my followers on Twitter recently put it, this is a First World Problem: a relatively healthy, economically and politically secure white male won't be able to spend hours each week indulging himself in frivolous athletic activity for purely personal gain. I think I'll survive.

Still, it's a shock, one that I may not get used to for a while. I'm not a runner any more.

Posted by Eugene Wallingford | Permalink | Categories: Personal, Running

April 27, 2011 6:12 PM

Teachers and Mentors

I'm fortunate to have good relationships with a number of former students, many of whom I've mentioned here over the years. Some are now close friends. To others, I am still as their teacher, and we interact in much the same way as we did in the classroom. They keep me apprised of their careers and occasionally ask for advice.

I'm honored to think that a few former students might think of me as their mentor.

classic image of Telemachus and Mentor

Steve Blank recently captured the difference between teacher and mentor as well as I've seen. Reflecting back to the beginning of his career, he considered what made his relationships with his mentors different from the relationship he had with his teachers, and different from the relationship his own students have with him now. It came down to this:

I was giving as good as I was getting. While I was learning from them -- and their years of experience and expertise -- what I was giving back to them was equally important. I was bringing fresh insights to their data. It wasn't that I was just more up to date on current technology, markets or trends; it was that I was able to recognize patterns and bring new perspectives to what these very smart people already knew. In hindsight, mentorship is a synergistic relationship.

In many ways, it's easier for a teacher to remain a teacher to his former students than to become a mentor. The teacher still feels a sense of authority and shares his wisdom when asked. The role played by both teacher and student remains essentially the same, and so the relationship doesn't need to change. It also doesn't get to grow.

There is nothing wrong with this sort of relationship, nothing at all. I enjoy being a teacher to some of my once and future students. But there is a depth to a mentorship that makes it special and harder to come by. A mentor gets to learn just as much as he teaches. The connection between mentor and young colleague does not feel as formal as the teacher/learner relationship one has in a classroom. It really is the engagement of two colleagues at different stages in their careers, sharing and learning together.

Blank's advice is sound. If what you need is a coach or a teacher, then try to find one of those. Seek a mentor when you need something more, and when you are ready and willing to contribute to the relationship.

As I said, it's an honor when a former student thinks of me as a mentor, because that means not only do they value my knowledge, expertise, and counsel but also they are willing to share their knowledge, expertise, and experience with me.

Posted by Eugene Wallingford | Permalink | Categories: Personal, Teaching and Learning

April 03, 2011 10:07 AM

Runner, Interrupted

Have you ever confused a dream with life?

I haven't blogged about running in a long while. Then again, I haven't run in a while now.

If you'd rather not hear me whine about that, you should skip the rest of this post!

I was getting through winter well enough, running 30+ miles each week. The coldest weather wasn't even stopping me; long, cold runs were the norm on Sunday mornings.

On March 4, I ran a good track workout, but as the day wore on I knew I wasn't feeling well. What ensued was the worst flu or something that I can remember. It knocked me out for two full weeks, through SIGCSE and spring break. I made it to Dallas for the conference, but my paucity of SIGCSE-themed posts was certainly a product of just how bad I felt.

Just as I was ready to start running again, my right knee became the problem. I don't recall suffering any particular injury to it at the time. I woke up one day with a stiff knee. Within a couple days I felt pain while walking, and soon it was swollen and stiffer.

It's now been two weeks more. I'm still hobbling around, knee wrapped tightly to immobilize it. The swelling and pain have decreased, and I hope that means I am on a trajectory to normal function. I have a second doctor's appointment this coming week. With any luck, an MRI will be able to tell us what is going on in there.

While I don't recall suffering any particular injury to the knee recently, I suspect that this is related to an injury I do remember. In 1999, I was at ChiliPLoP. We were playing doubles tennis after a long day working on elementary patterns. About an hour in, I was back and my partner was at the net. One of our opponents hit a bunny that floated enticingly over the net on my side of the court. I called my partner off and ran in for what would be an impressive smash. My partner must not have heard me. He ran along the net, apparently with the same idea in mind. As I stretched out to strike the ball, he struck me -- solidly on the inside of my knee, which buckled outwards.

For the rest of ChiliPLoP, I was pretty well immobile. After I returned home, I went to a highly respected orthopedic surgeon. He suggested a conservative plan, letting the knee heal and then strengthening it with targeted exercise. If all seemed well, we would skip surgery and see what happened.

After rest and exercise, the knee seemed fine, so we let it be. And so it was for twelve years. And just twelve years of sedentary lifestyle. Since 2003, I have kept close records of my running, and by my tally I have run about 13,000 miles. In all that time, I've never had any knee pain, and scant few days of running lost to injury. This injury could be the result of cumulative wear and tear, but I really would have expected to see symptoms of the wearing down over time.

I do hope that the doctor can figure out what's going on. With any luck, it's an aberration, and I'll be back on the trail soon!

(Writing this reminds me that I still haven't posted my Running Year in Review for 2010. I have started it a time or two and need only to finish. You'd think that not running would give me plenty of time...)

Posted by Eugene Wallingford | Permalink | Categories: Personal, Running

January 28, 2011 1:35 PM

A Great Job

The latest newsletter from my graduate alma mater mentioned that one of my favorite profs is retiring. I always considered myself fortunate to have studied AI with him in my first term of grad school and later to have worked as a TA with him when he taught the department's intro course. I learned a lot from both experiences. The AI course taught me a lot about how to be a scientist. The intro course taught me a lot about how to be a teacher.

I often hear about how faculty at research schools care only about their research and therefore make for bad teachers in the undergraduate classroom. There are certainly instances of this stereotype, but I think it is not generally true. Active researchers can be bad teachers, but then again so can faculty who aren't active in research. Working as this prof's TA, I saw that even good researchers can be very good undergraduate teachers. He cared about his students, cared about their learning, and prepared his classes carefully. Those are important ingredients for good teaching no matter who is doing it.

I dropped him a quick e-mail to thank him for all his guidance while I was in grad school and to wish him well in retirement. In his response, he expressed a sentiment many teachers will recognize:

I'm sure you have been in the university business long enough to realize what a great job we have. Working with students such as you has been very rewarding.

I have, indeed, been in the university business long enough to realize what a great job we professors have. Over the years, I've had the good fortune to work with some amazing students, both undergrad and grad. That joy comes as part of working with a lot of wonderful young people along their path to professional careers and meaningful lives.

When you add the opportunity to work with students and the opportunity to explore interesting ideas and follow where they might lead us, you get a nearly unbeatable combination. It's good for me to step back every once in a while and remember that.

Posted by Eugene Wallingford | Permalink | Categories: Personal, Teaching and Learning

January 21, 2011 10:38 AM

A Lot To Learn This Semester

It's been a good start to semester, though too busy to write much.

My Intelligent Systems course shows promise, with four teams of students taking on some interesting projects: recognizing faces, recognizing sign language, classifying transactions in a big-data finance context, and a traditional knowledge-based system to do planning. I am supervising a heavier-than-usual set of six individual research projects, including a grad student working on progressive chess and undergrads working on projects such as a Photoshop-to-HTML translator, an interpreter for a homoiconic OO language, and pure functional data structures. This all means that I have a lot to learn this semester!

I'm also still thinking about the future, as the dean's 3-year review of my work as department head proceeds. Yesterday I watched the video of Steve Jobs's commencement address at Stanford. This time around, his story about the freeing power of death grabbed special attention. Jobs gets up each day and asks himself, "If this is your last day on Earth, will you be happy doing what you are doing today?" If the answer is "no" too many days in a row, then he knows he needs to make a change.

That's a bracing form daily ritual. When it comes to this level of self-honesty, on most days I feel more like Howard W. Campbell, Jr. than Steve Jobs. I think I also finally grok this aphorism, a favorite saying of a friend: "Real men don't accept tenure". It can be an unhealthy form of academic immortality.

The question I ask myself more often than not these days is, "Are you programming?" Let me substitute "programming" for "writing" in a passage by Norman Fischer quoted at What I've Learned So Far:

... programming is a sort of absolute bottom line. "Are you programming?" If the answer is yes, then no matter what else is going on, your life -- and all of life -- is basically OK. You are who you are supposed to be, and your existence makes sense. If the answer is no, then you are not doing well, your relationships and basic well-being are in jeopardy, and the rest of the world is dark and problematic.

A day without writing code is like, you know, night. (With apologies to Steve Martin.)

Posted by Eugene Wallingford | Permalink | Categories: Personal, Teaching and Learning

January 15, 2011 11:34 AM

Paying Memories Forward

When you run a road race, you usually receive some token, usually a ribbon or a medal. The longer the race, the more likely you are to receive a medal, but even shorter distances these days often come with a medal. For marathons and half-marathons, the race medal is often a Very Big Deal, both for race sponsors and the runners.

Here is an example, from the 2004 Des Moines Marathon:

2004 Des Moines Marathon -- This ain't no cornfield.

Local color plus attitude -- this is a great design!

For many runners, the race medal is an important memento. I appreciate this feeling and understand the desire to keep and display the symbol of their achievement. This feeling is perhaps strongest in first-time and one-time marathoners, who rightly see their race as the culmination of a much longer journey.

After a while, though, these mementos begin to pile up. I have run seven marathons, many half-marathons, and many more shorter races, and the result was a box full of ribbons, medals, and medallions. Over the last year or so, I have been working to reduce clutter in my house and mind, which has led me to ask myself some tough questions about the role of keepsakes. In the grand scheme of things, a shoebox of race medals is no big deal, but it was really just one manifestation of my habit of stockpiling memories: ticket stubs; programs from plays, recitals, and school programs; newspaper and magazine clippings; and, yes, race memorabilia. The list goes on. I wanted to make a change: to keep fewer physical keepsakes and to work harder to preserve the memories themselves.

Could I really give up my race medals? If so, could I just throw them away?

Walking around the race expo for the 2010 Des Moines Marathon, I discovered a better way. There I learned that about Medals4Mettle, a non-profit founded in my hometown of Indianapolis that collects marathon finisher's medals and distributes them to people who have "demonstrated similar mettle" by dealing with disease, handicaps, and other challenges:

As marathoners run through the streets, large crowds cheer the runners for their effort. Medals4Mettle lets these runners, healthy enough to compete in such an event, return the cheers to those who have supported them.

Why should my medals gather dust in a box in my basement when they could cheer up a child facing a real challenge? I finish these races through a combination of great luck in birth and in life. Put in context, my accomplishments are small.

The Iowa chapter of Medals4Mettle seems to be primarily the work of one man, Jason Lawry, a Des Moines runner. I was touched by his commitment, took his card, and ran my race.

Over Christmas break, I pulled the trigger and donated my medals to Jason's group. First, I snapped digital photos of every marathon and half-marathon medal in my box. Not being a great photographer or the owner of an awesome camera, this took a while, but it allowed me to spend some time saying good-bye to my medals. In the end, I showed a small bit of weakness and kept three. The 2003 Chicago Marathon was my first and so holds a special place with me:

2003 Chicago Marathon -- my first

I ran the 2009 500 Festival Mini-Marathon in my hometown after two years of unexplained illness that brought racing and most running to a halt:

2009 500 Festival Mini-Marathon -- my hometown

Finally, there is something about running the 2007 Marine Corps Marathon that will always stick with me. Sharing the course with our nation's military, both veterans and active duty, inspired me. Receiving this medal from uniformed Marines makes it special:

2007 Marine Corps Marathon -- Semper Fidelis

Keeping three mementoes with particular significance seemed okay, though they might well mean more to someone else. Perhaps I'll donate these medals later, as memories fade or as new ones take on greater significance. I was proud to drop off the rest of them at a local runner's store for collection by Mr. Lawry.

And, no, I did not keep that cool 2004 Des Moines medal with the gangsta Grant Wood theme. I hope it brings a smile to the face of a person who can use the smile.

Posted by Eugene Wallingford | Permalink | Categories: Personal, Running

December 24, 2010 1:50 PM

Unexpected Gifts

Last evening, my wife and I attended the wedding of one of my former graduate students. He is from India, and his new wife is from Russia. This was a small ceremony and party, with only a few of their closest friends. They will have big celebrations in their homelands next year to commemorate the marriage with extended family. This celebration consisted of a simple civil ceremony, beautiful wedding vows, and lots of fun courtesy of their multicultural friends.

I was honored that he asked me to attend, and more honored that he considers me a close enough friend to invite to such a small and intimate affair. He arrived at my university as a student in one of my classes. Soon, he chose to work with me as his thesis advisor. In the years since he graduated, we have become colleagues and friends, talking first about our careers then about our lives. I consider him to be a friend of the highest order.

The academic world sometimes delivers great gifts to us. There was no particular reason for this talented, hard-working, generous, and loyal young man to arrive on our doorstep, among all the many schools he could have chosen. When he did, I received the good fortune of working with him academically for two years and then the good fortune of a great friend thereafter.

One of the traditions the groom and bride celebrated at their wedding was that anyone who wanted to give a toast could do so. Nearly everyone in attendance who knew either of them did so, and the groom himself spoke several times. About half way through the dinner and social time, my friend addressed the group, answering the often-asked question, how does a young man from Hyderabad end up at regional university in the middle of America's cornfields? He told a story about the e-mail he and I exchanged as he looked for an American grad school. Though we did not know it at the time, that was the beginning of our friendship.

This story honored me, far beyond the wedding invitation, and humbled me. It was an unexpected gift as the snow began to fall at the outset of the holiday weekend.

I wish Shri and Katya a lifetime of love and their own deep friendship. A friend is an eternal gift.

Posted by Eugene Wallingford | Permalink | Categories: Personal

December 22, 2010 2:27 PM

Thinking Ahead to Next Year, A Week Early

This is my last day at the office before Christmas, and my mind has turned to 2011 already. I'll do some work next week but hope to spend most of my week celebrating the holiday with my families. Besides, this is the time when a professor mind naturally turns to spring semester courses.

I have another reason to think about the future. This is the last year of my second three-year term as department head, so the dean is conducting a review of my performance. Implicit in these reviews is that it's a natural time for the dean to decide whether to continue with the current head or go in a different direction.

The head also makes the decision. There is a lot I like about being a department head, and a lot that I can do to help the faculty and students that I could not do otherwise. But it changes the shape and tenor of every day. At research schools, chairs often count the days of their terms from Day One. For a guy who is a researcher, programmer, or teacher at heart, there is precious little time to think about and do those things.

I head into to breaking thinking about the future. I have a lot of people's words rolling around in my head. Last week, Seth Godin said

If someone asks you ["What are you working on?"], are you excited to tell them the answer?

I hope so. If not, you're wasting away.

Last year, Chad Fowler asked:

But I think a good first step is to ask yourself the question: "What would I rather be doing right now?" And then, "Why is that not what I'm doing?"

... and Derek Sivers exclaimed:

No more yes. It's either HELL YEAH! or no.

... and Hugh MacLeod doodled: Life is too short not to do something that matters.

Gaping Void: Life is too short...

The recurring theme is: Take control of life. Don't drift. Don't let others determine your life. Godin goes an extra step and reminds us that we can apply this advice without changing our careers or job titles:

No matter what your job is, no matter where you work, there's a way to create a project ... where the excitement is palpable.... Hurry, go do that.

Plenty for my mind, conscious and subconscious, to mull over.

Posted by Eugene Wallingford | Permalink | Categories: Personal

December 18, 2010 11:34 AM

Some People Get Stuff Done

On Thursday, my students presented their Klein compilers. Several of the groups struggled with code generation, which is a common experience in a compiler course. There are a lot of reasons, most prominently that it's a difficult task. (Some students' problems were exacerbated by not reading the textbook...)

Still, all four groups managed to get something working for a subset of the language. They worked really hard, sometimes trying crazy ideas, all in an effort to make it work.

Over the years, I have noticed that some students have this attribute: they find a way to get things done. Whatever constraints they face, even under sub-optimal conditions they create for themselves, they find a way to solve the problem or make the program meet the spec. I'm surprised how often some students get things done despite not really understanding what they are doing! (Of course, sometimes, you just gotta know stuff.)

This reminds me of a conversation I had at Clemson University back in 1994 or 1995. I was attending and NSF workshop on closed labs. We were attending the midweek social event that seems de rigeur at weeklong workshops, chatting with some Clemson CS profs who had joined us for the evening and some AP CS graders who were also stationed at Clemson for the week. The AP folks talking about grading programs, the sort our students write in AP CS, CS1 and CS2.

One Clemson prof was surprised by how much weight the CS1 profs give to style, documentation, and presentation, relative to correctness. He said that he taught CS1 differently. Programming is hard enough, he said, that if you can find students who can wrote code, you should do whatever you can to encourage and develop them. We can teach style, presentation, and documentation standards to those students. Trying to teach more advanced programming skills to people who produce nice-looking programs but don't seem to "get it" is much, much harder.

He was expressing a preference for students who get stuff done.

In practice, students who major in CS from all across the spectrum. As a professor, I would like for my courses and our academic programs to help develop the "gets things done" attribute in our students, wherever they start along the spectrum. This requires that we help them grow not only in knowledge but also work habits. Perhaps most important is to help students develop a certain attitude toward problems, a default way of confronting the challenges they invariably encounter. Attitudes do not change easily, but they can evolve slowly over time. We profs can set a good example in how we confront challenges in class. We can also create conditions that favor a resilient approach to tough problems.

It was good for me to end the semester -- and the 2010 calendar year -- seeing that, whether by nature or nurture, some of our CS majors manage to get stuff done. That bodes well for success when they leave here.

Posted by Eugene Wallingford | Permalink | Categories: Personal, Teaching and Learning

December 15, 2010 4:30 PM

You May Be A Programmer If ... #1

... you get to the code generation part of the compiler course you are teaching. You realize that you have forgotten the toy assembly language from the textbook for its toy virtual machine, so you have to relearn it. You think, "It's gonna be fun to write programs in this language again."

Assembly language? A toy assembly language? Really?

I just like to program. Besides, after programming in Klein this semester, a language I termed as an integer assembly language, moving to a very RISC assembly doesn't seem like that big a step down. Assembly language can be fun, though I don't think I'd want to program in it for a living!

Posted by Eugene Wallingford | Permalink | Categories: Computing, Personal

November 24, 2010 9:15 PM

Thankful for Challenges and Progress

I watched A League of Their Own with my wife and daughters tonight.

It's supposed to be hard. If it wasn't hard, everybody would do it. The hard... is what makes it great.

-- Coach Jimmy Dugan

I'm thankful for the hard that makes so many of my experiences great. I'm also thankful to live in a world where my daughters have as many opportunities as they do to find and do whatever makes them whole.

Posted by Eugene Wallingford | Permalink | Categories: Personal

November 22, 2010 2:18 PM

Tragedy and the Possibilities of Unlimited Storage

I've spent considerable time this morning cleaning out the folder on my desktop where I keep stuff. In one the dozens of notes files I've created over the last year or so, I found this unattributed quote:

In 1961, the scholar and cultural critic George Steiner argued in a controversial book, "The Death of Tragedy", that theatrical tragedies had begun their steady decline with the rise of rationalism and the Enlightenment in the 17th century. The Greek notion of tragedy was premised on man's inability to control his fate in the face of capricious, often brutal gods. But the point of a tragedy was to dramatize man's ability to make choices whatever his uncontrollable end.

The emphasis was not on the death -- what the gods usually had in store -- but on what the hero died for: the state, love, his own dignity. Did he die nobly? Or with shame? For a worthy cause? Or pitiless self-interest? Tragedies, then, were ultimately "an investigation into the possibilities of human freedom", as Walter Kerr put it in "Tragedy and Comedy" (1967).

I like this passage now as much as I must have when I typed it up from some book I was reading. (I'm surprised I did not write down the source!) It reminds me that I face and make choices every day that reveal who I am. Indeed, the choices I make create who I am. That message feels especially important to me today.

And yes, I know there are better tools for keeping notes than dozens of text files thrown into nearly as many folders. I take notes using a couple of them as well. Sometimes I lack the self-discipline I need to leave an ordered life!

Posted by Eugene Wallingford | Permalink | Categories: General, Personal

November 13, 2010 9:28 AM

Shape, or Be Shaped

Playwright Arthur Miller is often quoted as saying:

Man must shape his tools lest they shape him.

I read this again yesterday, in the online book Focus, while listening to faculty at a highly-ranked local school talk about the value of a liberal arts education. The quote reminds me about one of the reasons I so like being a computer scientist. I can shape my tools. If I need a new tool, or even a new kind of tool, I can make it.

Our languages are tools, too. We can shape them, grow them, change them. We can create new ones. (Thanks, Matz.)

Via the power of the Internet I am continuously surrounded by colleagues smarter and more motivated than I doing the same. I've been enjoying watching Brian Marick tweet about his thoughts and decision making as he implements Midje in Clojure. His ongoing dialog reminds me that I do not have to settle.

Posted by Eugene Wallingford | Permalink | Categories: Computing, Personal

November 03, 2010 2:12 PM

Ideas from Readers on Recent Posts

A few recent entries have given rise to interesting responses from readers. Here are two.

Fat Arrows

Relationships, Not Characters talked about how the most important part of design often lies in the space between the modules we create, whether objects or functions, not the modules themselves. After reading this, John Cook reminded me about an article by Thomas Guest, Distorted Software. Near the end of that piece, which talks about design diagrams, Guest suggests that the arrows in application diagrams should be larger, so that they would be proportional to the time their components take to develop. Cook says:

We typically draw big boxes and little arrows in software diagrams. But most of the work is in the arrows! We should draw fat arrows and little boxes.

I'm not sure that would make our OO class diagrams better, but it might help us to think more accurately!

My Kid Could Do That

Ideas, Execution, and Technical Achievement wistfully admitted that knowing how to build Facebook or Twitter isn't enough to become a billionaire. You have to think to do it. David Schmüdde mentioned this entry in his recent My Kid Could Do That, which starts:

One of my favorite artists is Mark Rothko. Many reject his work thinking that they're missing some genius, or offended that others see something in his work that they don't. I don't look for genius because genuine genius is a rare commodity that is only understood in hindsight and reflection. The beauty of Rothko's work is, of course, its simplicity.

That paragraph connects with one of the key points of my entry: Genius is rare, and in most ways irrelevant to what really matters. Many people have ideas; many people have skills. Great things happen when someone brings these ingredients together and does something.

Later, he writes:

The real story with Rothko is not the painting. It's what happens with the painting when it is placed in a museum, in front of people at a specific place in the world, at a specific time.

In a comment on this post, I thanked Dave, and not just because he discusses my personal reminiscence. I love art but am a novice when it comes to understanding much of it. My family and I saw an elaborate Rothko exhibit at the Smithsonian this summer. It was my first trip to the Smithsonian complex -- a wonderful two days -- and my first extended exposure to Rothko's work. I didn't reject his art, but I did leave the exhibit puzzled. What's the big deal?, I wondered. Now I have a new context in which to think about that question and Rothko's art. I didn't expect the new context to come from a connection a reader made to my post on tech start-up ideas that change the world!

I am glad to know that thinkers like Schmüdde are able to make connections like these. I should note that he is a professional artist (both visual and aural), a teacher, and a recovering computer scientist -- and a former student of mine. Opportunities to make connections arise when worlds collide.

Posted by Eugene Wallingford | Permalink | Categories: Computing, Patterns, Personal, Software Development

October 28, 2010 4:27 PM

Ideas, Execution, and Technical Achievement

Four or five years ago, my best buddy on campus and I were having lunch at our favorite Chinese buffet. He looked up between bites of General Tsao's and asked, "Why didn't you and I sit down five years ago and write Facebook?"

You see, he is an awesome programmer and has worked with me enough to know that I do all right myself. At various times, both of us have implemented bits and pieces of the technology that makes up Facebook. It doesn't look like all that big a deal.

I answered, "Because we didn't think of it."

The technical details may or may not have been a big deal. Once implemented, they look straightforward. In any case, though, the real reason was that it never occurred to us to write Facebook. We were techies who got along nicely with the tools available to us in 1999 or 2000, such as e-mail, wiki, and the web. If we needed to improve our experience, we did so by improving our tools. Driven by one of his own itches, Troy had done his M.S. research with me as his advisor, writing a Bayesian filter to detect spam. But neither of us thought about supplanting e-mail with a new medium.

We had the technical skills we needed to write Facebook. We just didn't have the idea of Facebook. Turns out, that matters.

That lunch conversation comes into my mind every so often. It came back yesterday when I read Philip Greenspun's blog entry on The Social Network. Greenspun wrote one of my favorite books, Philip and Alex's Guide to Web Publishing, which appeared in 1998 and which describes in great detail (and with beautiful photos) how to implement web community software. When his students ask how he feels about Zuckerberg getting rich without creating anything "new", Greenspun gives a wonderfully respectful and dispassionate answer: "I didn't envision every element of Facebook." Then he explains what he means.

Technically, Greenspun was positioned as well or better than my buddy and I to write Facebook. But he didn't the idea, either, at least not to the same level as Zuckerberg. Having the core of an idea is one thing. Developing it to the point that it becomes a platform that changes the world in which it lives is another. Turns out, that matters, too.

I like Lawrence Lessig's most succinct summation of what makes Zuckerberg writing Facebook a notable achievement: He did it. He didn't just have an idea, or talk about it, or dream about it. He implemented it.

That's what great hackers do.

Watch this short video to hear Zuckerberg himself say why he built. His answer is also central to the hacker ethic: Because he wanted to.

(Also read through to the end of Lessig's article for a key point that many people miss when they think about the success and achievement of things like Facebook and Twitter and Napster: The real story is not the invention.

Zuckerberg may or may not be a genius? I don't know or care. That is a word that modern culture throws around far too carelessly these days. I will say this. I don't think that creating Facebook is in itself sufficient evidence for concluding so. A lot of people have cool ideas. A more select group of people write the code to make their ideas come alive. Those people are hackers. Zuckerberg is clearly a great hacker.

I'm not a big Facebook user, but it has been on my mind more than usual the last couple of days. Yesterday was my birthday, and I was overwhelmed by all the messages I received from Facebook friends wishing me a happy day. They came from all corners of the country; from old grade-school friends I haven't seen in over thirty years; from high school and college friends; from professional friends and acquaintances. These people all took the time to type a few words of encouragement to someone hundreds of miles away in the middle of the Midwest. I felt privileged and a little humbled.

Clearly, this tool has made the world a different place. The power of the social network lies in the people. The technology merely enables the communication. That's a significant accomplishment, even if most of the effects are beyond what the creator imagined. That's the power of a good idea.


All those years ago, my buddy and I talked about how little technical innovation there was in Facebook. Greenspun's answer reminds us that there was some. I think there is another element to consider, something that was a driving force at StrangeLoop: big data. The most impressive technical achievement of Facebook and smaller web platforms such as Twitter is the scale at which they operate. They've long ago outgrown naive implementations and have had to try to offer uninterrupted service in the face of massive numbers of users and exponential growth. Solving the problems associated with operating at such a scale is an ongoing technical challenge and a laudable achievement in its own right.

Posted by Eugene Wallingford | Permalink | Categories: Computing, Personal

October 16, 2010 7:59 PM

Strange Loop This and That

Some miscellaneous thoughts after a couple of days in the mix...

Pertaining to Knowing and Doing

** Within the recurring theme of big data, I still have a few things to study: MongoDB, CouchDB, and FlockDB. I also learned about Pig, a language I'd never heard of before. I think I need to learn it.

** I need to be sure that my students learn about the idea of multimethods. Clojure has brought them back into mainstream discussion.

** Kevin Weil, who spoke about NoSQL at Twitter, told us that his background is math and physics. Not CS. Yet another big-time developer who came to programming from another domain because they had real problems to solve.

Pertaining to the Conference

** The conference served soda all day long, from 8:00 in the morning to the end of the day. Hurray! My only suggestion: add Diet Mountain Dew to the selections.

** The conference venues consist of two rooms in a hotel, two rooms in a small arts building, and the auditorium of the Pageant Theater. The restrooms are all small. During breaks, the line for the men's room was, um, long. The women in attendance came and went without concern. This is exactly opposite of what one typically sees out in public. The women of Strange Loop have their revenge!

** This is the first time I have ever attended a conference with two laptop batteries. And I saw that it was good. Now, I just have to find out why every couple of weeks my keyboard and trackpad freeze up and effectively lock me out. Please, let it not be a failing mother board...

Pertaining to Nothing But Me

** Like every conference, Strange Loop fills the silence between sessions with a music loop. The music the last two days has been aimed at its audience, which is mostly younger and mostly hipper than I am. I really enjoyed it. I even found a song that will enter my own rotation, "Hey, Julie" by Fountains of Wayne. You can, of course, listen to it on YouTube. I'll have to check out more Fountains of Wayne later.

** On Twitter, I follow a relatively small number of people, mostly professional colleagues who share interesting ideas and links. I also follow a few current and former students. Rounding out the set are a couple connections I made with techies through others, back when Twitter was small. I find that I enjoy their tweets even though I don't know them, or perhaps because I don't.

On Thursday, it occurred to me: Maybe it would be fun to follow some arbitrary incredibly popular person. During one of the sessions, we learned that Lady Gaga has about 6,500,000 followers, surpassing Ashton Kutcher's six million. I wonder it would be like to have their tweets flowing in a stream with those of Brian Marick and Kevlin Henney, Kent Beck and Michael Feathers.

Posted by Eugene Wallingford | Permalink | Categories: Computing, Personal

October 13, 2010 10:20 PM

Serendipitous Connections

I'm in St. Louis now for Strange Loop, looking at the program and planning my schedule for the next two days. The abundant options nearly paralyze me... There are so many things I don't know, and so many chances to learn. But there are a limited number of time slots in any day, so the chances overlap.

I had planned to check in at the conference and then eat at The Pasta House, a local pasta chain that my family discovered when we were here in March. (I am carbo loading for the second half of my travels this week.) But after I got the motel, I was tired from the drive and did not relish getting into my car again to battle the traffic again. So I walked down the block to Bartolino's Osteria, a more upscale Italian restaurant. I was not disappointed; the petto di pollo modiga was exquisite. I'll hit the Pasta House tomorrow.

When I visit big cities, I immediately confront the fact that I am, or have become, a small-town guy. Evening traffic in St. Louis overwhelms my senses and saps my energy. I enjoy conferences and vacations in big cities, but when they end I am happy to return home.

That said, I understand some of the advantages to be found in large cities. Over the last few weeks, many people have posted this YouTube video of Steven Johnson introducing his book, "Where Good Ideas Come From". Megan McArdle's review of the book points out one of the advantages that rises out of all that traffic: lots of people mean lots of interactions:

... the adjacent possible explains why cities foster much more innovation than small towns: Cities abound with serendipitous connections. Industries, he says, may tend to cluster for the same reason. A lone company in the middle of nowhere has only the mental resources of its employees to fall back on. When there are hundreds of companies around, with workers more likely to change jobs, ideas can cross-fertilize.

This is one of the most powerful motivations for companies and state and local governments in Iowa to work together to grow a more robust IT industry. Much of the focus has been on Des Moines, the state capitol and easily the largest metro area in the state, and on the Cedar Rapids/Iowa City corridor, which connects our second largest metro area with our biggest research university. Those areas are both home to our biggest IT companies and also home to a lot of people.

The best IT companies and divisions in those regions are already quite strong, but they will be made stronger by more competition, because that competition will bring more, and more diverse, people into the mix. These people will have more, and more diverse, ideas, and the larger system will create more opportunities for these ideas to bounce off one another. Occasionally, they'll conjoin to make something special.

The challenge of the adjacent possible makes me even more impressed by start-ups in my small town. People like Wade Arnold at T8 Webware are working hard to build creative programming and design shops in a city without many people. They rely on creating their own connections, at places like Strange Loop all across the country. In many ways, Wade has to think of his company as an incubator for ideas and a cultivator of people. Whereas companies in Des Moines can seek a middle ground -- large enough to support the adjacent possible but small enough to be comfortable -- companies like T8 must create the adjacent possible in any way they can.

Posted by Eugene Wallingford | Permalink | Categories: General, Personal

October 02, 2010 9:38 PM

Your Voice Cannot Command

I've been carrying this tune in my mind for the last couple of days, courtesy of singer-songwriter and fellow Indianapolis native John Hiatt:

So whatever your hands find to do
You must do with all your heart
There are thoughts enough
To blow men's minds and tear great worlds apart


Don't ask what you are not doing
Because your voice cannot command
In time we will move mountains
And it will come through your hands

One of my deepest hopes as a parent is that I can help my daughters carry this message with them throughout their lives.

I also figure I'll be doing all right as a teacher if my students take this message with them when they graduate, whether or not they remember anything particular about design patterns or lambda.

Posted by Eugene Wallingford | Permalink | Categories: Personal, Teaching and Learning

September 29, 2010 9:27 PM

The Manifest Destiny of Computer Science?

The June 2010 issue of Communications of the ACM included An Interview with Ed Feigenbaum, who is sometimes called the father of expert systems. Feigenbaum was always an ardent promoter of AI, and time doesn't seem to have made him less brash. The interview closes with the question, "Why is AI important?" The father of expert systems pulls no punches:

There are certain major mysteries that are magnificent open questions of the greatest import. Some of the things computer scientists study are not. If you're studying the structure of databases -- well, sorry to say, that's not one of the big magnificent questions.

I agree, though occasionally I find installing and configuring Rails and MySQL on my MacBook Pro to be one of the great mysteries of life. Feigenbaum is thinking about the questions that gave rise to the field of artificial intelligence more than fifty years ago:

I'm talking about mysteries like the initiation and development of life. Equally mysterious is the emergence of intelligence. Stephen Hawking once asked, "Why does the universe even bother to exist?" You can ask the same question about intelligence. Why does intelligence even bother to exist?

That is the sort of question that captivates a high school student with an imagination bigger than his own understanding of the world. Some of those young people are motivated by a desire to create an "ultra-intelligent computer:, as Feigenbaum puts it. Others are motivated more by the second prize on which AI founders set their eyes:

... a very complete model of how the human mind works. I don't mean the human brain, I mean the mind: the symbolic processing system.

That's the goal that drew the starry-eyed HS student who became the author of this blog into computer science.

Feigenbaum closes his answer with one of the more bodacious claims you'll find in any issue of Communications:

In my view the science that we call AI, maybe better called computational intelligence, is the manifest destiny of computer science.

There are, of course, many areas of computer science worthy of devoting one's professional life to. Over the years I have become deeply interested in questions related to language, expressiveness, and even the science or literacy that is programming. But it is hard for me to shake the feeling, still deep in my bones, that the larger question of understanding what we mean by "mind" is the ultimate goal of all that we do.

Posted by Eugene Wallingford | Permalink | Categories: Computing, Personal

September 23, 2010 10:24 PM

Distracted All the Time, or "Warped by YouTube"

A friend sent me an e-mail message last night that said, among other things, "So, you've been recruiting." I began my response with, "It's a hard habit to break." Immediately, this song was in my ear. I had an irrational desire to link to it, or mention it, or at least go play it. But I doubt Rick cared to hear it, or even hear about my sudden obsession with it, and I had too much to do to take the time to surf over to YouTube and look it up.

Something like this happens to me nearly every time I sent down to write, especially when I blog. The desire to pack my entries with a dense network of links is strong. Most of those links are useful, giving readers an opportunity to explore the context of my ideas or to explore a particular idea deeper. But every so often, I want to link to a pop song or movie reference whose connection to my entry is meaningful only to me.

YouTube did this to me. So did Hulu and Wikipedia and Google and Twitter, and the rest of the web.

What an amazing resource. What a joy to be able to meet an unexpected need or desire.

What a complete distraction.

It is hard for someone who remembers the world pre-web to overstate how amazing the resource is. These days, we are far more likely to be surprised not to find what we want than the other way around. Another friend expressed faux distress this morning when he couldn't find a video clip on-line of an old AT&T television commercial from the 70s or 80s with a Viking calling home to Mom. Shocking! The interwebs had failed him. Or Google.

Still there are days when I wonder how much having ubiquitous information at my fingertips has changed me for the worse, too. The costs of distraction are often subtle, an undertow on the flow of conscious thought. Did I really need to think about Chicago while writing e-mail about ChiliPLoP? The Internet didn't invent distraction, but it did make a cheap, universal commodity out of it.

Ultimately, this all comes back to my own weakness, the peculiar way in which my biology and experience have wired my mind for making connections, whether useful or useless. That doesn't mean the Internet isn't an enabler.

I am in a codependent relationship with the web. And we all know that a codependent relationship can be a hard habit to break.

Posted by Eugene Wallingford | Permalink | Categories: Personal

September 02, 2010 10:07 PM

Creation and the Beauty of Language

I learned today that my colleague Mark Jacobson created a blog last spring, mostly as a commonplace book of quotes on which he was reflecting. While looking at his few posts, I came across this passage from Rainer Maria Rilke in his inaugural entry:

If your daily life seems poor, do not blame it; blame yourself that you are not poet enough to call forth its riches; for the Creator, there is no poverty.

There were a couple of times this week when I really needed to hear this, and reading it today was good fortune. It's also a great passage for computer programmers, who need never accept the grayness of their tools because they have the powers of a Creator.

I have long been a fan of Rilke's imagery and have quoted him before. I remember reading my first Rilke poem, in my high school German IV course. Our wonderful teacher, Frau Griffith, had the heart of a poet and asked those of us who had survived into the fourth year to read as much original German literature as we could, in order that we might come to understand more fully what it means to be German. (She was a deeply emotional woman who had escaped Nazi Germany on a train in the dead of night, just ahead of the local police.) I came to love Rilke and to be mesmerized by Kafka, whose work I have read in translation many times since. His short fiction is often surprising.

I do not remember just which Rilke poem we read first. I only remember that it showed me German could be beautiful. My German IV classmates and I were often teased by classmates who studied French and Spanish. They praised the fluidity of their languages and mocked the turgid prose of ours. We mocked them back for studying easier languages, but secretly we admitted that German was sounded and looked uglier. Rilke showed us that we were wrong, that German syllables could flow as mellifluously as any other. Revelation!

Later Frau introduced us to the popular music of Udo Jürgens, and we were hooked.

Recently, I ran across a reference to Goethe's "The Holy Longing". I tracked it down in English and immediately understood its appeal. But the translation feels so clunky... The original German has a rhythm that is hard to capture. Read:

Keine Ferne macht dich schwierig,
Kommst geflogen und gebannt,
Und zuletzt, des Lichts begierig,
Bist du Schmetterling verbrannt.

That's not quite Rilke to my ears, but it feels right.

Posted by Eugene Wallingford | Permalink | Categories: Personal

September 01, 2010 9:12 PM

The Beginning of a New Project

"Tell me you're not playing chess," my colleague said quizzically.

But I was. My newest grad student and I were sitting in my office playing a quick couple of games of progressive chess, in which I've long been interested. In progressive chess, white makes one move, then black makes two; white makes three moves, then black makes four. The game proceeds in this fashion until one of the players delivers checkmate or until the game ends in any other traditional way.

This may seem like a relatively simple change to the rules of the game, but the result is something that almost doesn't feel like chess. The values of the pieces changes radically, as does the value of space and the meaning of protection. That's why we needed to play a couple of games: to acquaint my student with how different it is from the classical chess I know and love and which has played since a child.

For his master's project, the grad student wanted to do something in the general area of game-playing and AI, and we both wanted to work on a problem that is relatively untouched, where a few cool discoveries are still accessible to mortals. Chess, the fruit fly of AI from the 1950s into the 1970s, long ago left the realm where newcomers could make much of a contribution. Chess isn't solved in the technical sense, as checkers is, but the best programs now outplay even the best humans. To improve on the state of the art requires specialty hardware or exquisitely honed software.

Progressive chess, on the other hand, has a funky feel to it and looks wide open. We are not yet aware of much work that has been done on it, either in game theory or automation. My student is just beginning his search of the literature and will know soon how much has been done and what problems have been solved, if any.

That is why we were playing chess in my office on a Wednesday afternoon, so that we could discuss some of the ways in which we will have to think differently about this problem as we explore solutions. Static evaluation of positions is most assuredly different from what works in classical chess, and I suspect that the best ways to search the state space will be quite different, too. After playing only a few games, my student proposed a new way to do search to capitalize on progressive chess's increasingly long sequences of moves by one player. I'm looking forward to exploring it further, giving it a try in code, and finding other new ideas!

I may not be an AI researcher first any more, but this project excites me. You never know what you will discover until you wander away from known territory, and this problem offers us a lot of unknowns.

And I'll get to say, "Yes, we are playing chess," every once in a while, too.

Posted by Eugene Wallingford | Permalink | Categories: Computing, Personal

August 20, 2010 3:30 PM

Simplicity, Complexity, and Good Enough Chess Ratings

Andrew Gelman writes about a competition offered by Kaggle to find a better rating system for chess. The Elo system has been used for the last 40+ years with reasonable success. In the era of big data, powerful ubiquitous computers, and advanced statistical methods, it turns out that we can create a rating system that predicts more accurately the performance of players on games in the near-future. Very cool. I'm still enough of chess geek that I want to know just when Capablanca surpassed Lasker and how much better Fischer was than his competition in the 1972 challenger's matches. I've always had an irrational preference for ridiculously precise values.

Even as we find systems that perform better, I find myself still attached to Elo. I'm sure part of it is that I grew up with Elo ratings as a player, and read Elo's The Rating of Chess Players, Past and Present as a teen.

But there's more. I've also written programs to implement the rating system, including the first program I ever wrote out of passion. Writing the code to assign initial ratings to a pool of players based on the outcomes of games played among them required me to do something I didn't even know was possible at the time: start a process that wasn't guaranteed to stop. I learned about the idea of successive approximations and how my program would have to settle for values that fit the data well enough. This was my first encounter with epsilon, and my first non-trivial use of recursion. Yes, I could have written a loop, but the algorithm seemed so clear written recursively. Such experiences stick with a person.

There is still more, though, beyond my personal preferences and experiences. Compared to most of the alternatives that do a better job objectively, the Elo system is simple. The probability curve is simple enough for anyone to understand, and the update process is basic arithmetic. Even better, there is a simple linear approximation of the curve that made it possible for a bunch of high school kids with no interest in math to update ratings based on games played at the club. We posted a small table of expected values based on rating differences at the front of the room and maintained the ratings on index cards. (This is a different sort of index-card computing than I wrote about long ago.) There may have been more accurate systems we could have run, but the math behind this one was so simple, and the ratings were more than good enough for our purposes. I am guessing that the Elo system is more than good enough for most people's purposes.

Simple and good enough is a strong combination. Perhaps the Elo system will turn out to be the Newtonian physics of ratings. We know there are a better, more accurate models, and we use them whenever we need something very accurate. Otherwise, we stick to the old model and get along just fine almost all the time.

Posted by Eugene Wallingford | Permalink | Categories: Computing, Personal

July 22, 2010 4:19 PM

Days of Future Passed: Standards of Comparison and The Value of Limits

This morning, a buddy of mine said something like this as part of a group e-mail discussion:

For me, the Moody Blues are a perfect artist for iTunes. Obviously, "Days of Future Passed" is a classic, but everything else is pretty much in the "one good song on an album" category.

This struck as a reflection of an interesting way in which iTunes has re-defined how we think about music. There are a lot of great albums that everyone should own, but even for fans most artists produce only a song or two worth keeping over the long haul. iTunes makes it possible to cherry-pick individual songs in a way that relegates albums to second thought. A singer or band have achieved something notable if people want to buy the whole album.

That's not the only standard measure I encountered in that discussion.

After the same guy said, "The perfect Moody Blues disc collection is a 2-CD collection with the entirety of 'Days of Future Passed' and whatever else you can fit", another buddy agreed and went further (again paraphrased):

"Days of Future Passed" is just over half an 80-minute CD, and then I grabbed another 8 or 9 songs. That worked out right for me.

Even though CDs are semi-obsolete in this context, they still serve a purpose, as a sort of threshold for asking the question "How much music from this band do I really want to rip?"

When I was growing up, the standard was the 90-minute cassette tape. Whenever I created a collection for a band from a set of albums I did not want to own, I faced two limits: forty-five minutes on a side, and ninety minutes total. Those constraints caused me many moments of uncertainty as I tried to cull my list of songs into two lists that fit. Those moments were fun, though, too, because I spent a lot of time thinking about the songs on the bubble, listening and re-listening until I could make a comfortable choice. Some kids love that kind of thing.

Then, for a couple of decades the standard was the compact disc. CDs offered better quality with no halfway cut, but only about eighty minutes of space. I had to make choices.

When digital music leapt from the CD to the hard drive, something strange happened. Suddenly we were talking about gigabytes. And small numbers of gigabytes didn't last long. From 4- and 8-gigabyte devices we quickly jumped to iPods with a standard capacity of 160GB. That's several tens of thousands of songs! People might fill their iPods with movies, but most people won't ever need to fill them with the music they listen to on any regular basis. If they do, they always have the hard drive on the computer they sync the iPod with. Can you say "one terabyte", boys and girls?

The computer drives we use for music got so large so fast that they are no longer useful as the arbitrary limit on our collections. In the long run, that may well be a good thing, but as someone who has lived on both sides of the chasm, I feel a little sadness. The arbitrary limits imposed by LPs, cassettes, and CDs caused us to be selective and sometimes even creative. This is the same thing we hear from programmers who had to write code for machines with 128K of memory and 8 Mhz processors. Constraints are a source of creativity and freedom.

It's funny how the move to digital music has created one new standard of comparison via the iTunes store and destroyed another via effectively infinite hard drives. We never know quite how we and our world will change in response to the things we build. That's part of the fun, I think.

Posted by Eugene Wallingford | Permalink | Categories: Computing, Personal

July 19, 2010 4:48 PM

"I Blame Computers."

I spent the weekend in southwestern Ohio at Hueston Woods State Park lodge with a bunch of friends from my undergrad days. This group is the union of two intersecting groups of friends. I'm a member of only one but was good friends with the two main folks in the intersection. After over twenty years, with close contact every few years, we remain bonded by experiences we shared -- and created -- all those years ago.

The drives to and from the gathering were more eventful than usual. I was stopped by a train at same railroad crossing going both directions. On the way there, a semi driver intentionally ran me off the road while I was passing him on the right. I don't usually do that, but he had been driving in the left lane for quite a while, and none too fast. Perhaps I upset him, but I'm not sure how. Then, on the way back, I drove through one of the worst rainstorms I've encountered in a long while. It was scarier than most because it hit while I was on a five-lane interstate full of traffic in Indianapolis. The drivers of my hometown impressed me by slowing down, using their hazard lights, and cooperating. That was a nice counterpoint to my experience two days earlier.

Long ago, my mom gave me the New Testament of the Bible on cassette tape. (I said it was long ago!) When we moved to a new house last year, I came across the set again and have had it in pile of stuff to handle ever since. I was in an unusual mood last week while packing for the trip and threw the set in the car. On the way to Ohio, I listened to Gospel of Matthew. I don't think I have ever heard or read an entire gospel in one setting before. After hearing Matthew, I could only think, "This is a hard teaching." (That is a line from another gospel, by John, the words and imagery of which have always intrigued me more than the other gospels.)

When I arrived on Friday, I found that the lodge did offer internet service to the rooms, but at an additional cost. That made it easier for me to do what I intended, which was to spend weekend off-line and mostly away from the keyboard. I enjoyed the break. I filled my time with two runs (more on them soon) and long talks with friends and their families.

Ironically, conversation late on Saturday night turned to computers. The two guys I was talking with are lawyers, one for the Air Force at Wright Patterson Air Force Base and one for a U.S. district court in northern Indiana. Both lamented the increasing pace of work expected by their clients. "I blame computers," said one of the guys.

In the old days, documents were prepared, duplicated, and mailed by hand. The result was slow turnaround times, so people came to expect slow turnaround. Computers in the home and office, the Internet, and digital databases have made it possible to prepare and communicate documents almost instantly. This has contributed to two problems they see in their professional work. First, the ease of copy-and-paste has made it even easier to create documents that are bloated or off-point. This can be used to mislead, but in their experience the more pernicious problem is lack of thoughtfulness and understanding.

Second, the increased speed of communication has led to a change in peoples' expectations about response. "I e-mailed you the brief this morning. Have you resolved the issue this morning?" There is increasing pressure to speed up the work cycle and respond faster. Fortunately, both report that these pressures come only from outside. Neither the military brass nor the circuit court judges push them or their staff to work faster, and in fact encourage them to work with prudence and care. But the pressure on their own staff from their clients grows.

Many people lash out and blame "computers" for whatever ills of society trouble them. These guys are bright, well-read, and thoughtful, and I found their concerns about our legal system to be well thought out. They are deeply concerned by what the changes mean for the cost and equitability of the justice the system can deliver. The problem, of course, is not with the computers themselves but with how we use them, and perhaps with how they change us. For me as a computer scientist, that conversation was a reminder that writing a program does not always solve our problems, and sometimes it creates new ones. The social and cultural environments in which programs operate are harder to understand and control than our programs. People problems can be much harder to solve than technical problems. Often, when we solve technical problems, we need to be prepared for unexpected effects on how people work and think.

Posted by Eugene Wallingford | Permalink | Categories: Computing, Personal

June 29, 2010 3:22 PM

Half Past Summer

As department head, I teach only one course each semester, not the three that is standard for our faculty. The past academic year has been a bit unusual, though, with a load that kept me busy, busy, busy. In the fall, I taught Software Engineering, a course I had never taught before. My spring load included not only Programming Languages but also ten weeks of teaching Cobol two hours a week. I've taught Cobol many times before, but not for over fifteen years. Then, to top it all off, I taught my first May term course, an agile software dev course that met two hours every day for four weeks.

All of this was fun for the teacher in me, but no one turned down the spigot of administrative work pouring into my office. As a result, the year felt something like a treadmill. Then I spent a week digging out of a pile of undone work, eight days on vacation, and another week plus digging out of a new pile of undone work. With the delivery of faculty salary letters, I am ready to begin summer.

Fall classes begin in eight weeks -- a blink of an eye.

Posted by Eugene Wallingford | Permalink | Categories: Personal

May 31, 2010 8:48 PM

The End of the Day

... and a fine one, spent with family, enjoying the world. I recall a passage from Josef Albers:

calm down
what happens
happens mostly
without you

Thanks to David Schmüdde for reminding me of Albers's quiet aside.

Posted by Eugene Wallingford | Permalink | Categories: Personal

May 28, 2010 4:48 PM

Good Thing I Can Program...

A friend and colleague sent me this:

So I had a very strange dream last night. I almost never remember dreams, so this was worth bringing up.

You were in grad school ..., getting a second PhD (I think in psychology). I was there visiting you. You were single for some reason. Anyway, while I was there, you were accused of murdering another graduate student. The big evidence that they had of this was a video recording of you and your rock band (you were the lead singer) rehearsing for a gig. The other graduate student (Chinese girl) had been in the band, and suddenly she was totally missing from the video and your microphone was stained red. You and I had gotten a copy of the recording and were running from investigators. We finally got to a video editing lab on campus and were trying to figure out what was going on. We found a spot where the recording had clearly been edited. We were in the midst of finding the original recording when I woke up.

Boy would I like to have someone who interprets dreams take a whack at this one.

After I finish off my second Ph.D., I'm sure I'll be able to help with that.

It is perhaps sad that I am more interesting in my dreams than in real life, and sadder that I am more interesting in other people's dreams than in my own.

It's good to know that my ability to analyze video as data may well help me clear my good name!

Posted by Eugene Wallingford | Permalink | Categories: Personal

April 24, 2010 1:25 PM

Futility and Ditch Digging

First, Chuck Hoffman tweeted, The life of a code monkey is frequently depressingly futile.

I had had a long week, filled with the sort of activities that can make a programmer pine for days as a code monkey, and I replied, Life in many roles is frequently depressingly futile. Thoreau was right.

The ever-timely Brian Foote reminded me:

Sometimes utility feels like futility, but someone's gotta do it.

Thanks, Brian. I needed to hear that.

I remember hearing an interview with musician John Mellencamp many years ago in which he talked about making the movie Falling from Grace. Th interviewer was waxing on about the creative process and how different movies were from making records, and Mellencamp said something to the effect of, "A lot of it is just ditch digging: one more shovel of dirt." Mellencamp knew about that sort of manual labor because he had done it, digging ditches and stringing wire for a telephone company before making it as an artist. And he's right: an awful lot of every kind of working is moving one more shovel of dirt. It's not romantic, but it gets the job done.

Posted by Eugene Wallingford | Permalink | Categories: General, Personal

April 19, 2010 10:40 PM

Different Perspective on Loss

A house burned in my neighborhood tonight. I do not know yet the extent of the damage, but the fight was protracted. My first hope is that no one was hurt, neither residents of the house nor the men and women who battled the blaze.

Such a tragedy puts my family's recent loss into perspective. No matter how valuable our data, when a hard drive fails, no one dies. Even without a backup, life goes. Even without a backup, there is a chance of recovery. We can run utilities that come with our OS. We can run wonderful programs that cost little money. Specialists can pull the platters from the drive and attempt to read data raw.

Things lost in a fire are lost forever.

If we follow a few simple and well-known rules, we can have a backup: a bit-for-bit copy of our data, all our digital stuff, indistinguishable from the original. In principle and in practice, we can encounter failures and lose nothing. In the material world, we cannot make a copy of everything we own. Yes, we can make copies of important documents, and we can store some of our stuff somewhere else. But we don't live in a bizarro Steven Wright world where we possess an identical copy of every book, every piece of clothing, every memento.

In the digital world, we can make copies that preserve our world.

So, I type this with a different outlook. The world reminds me that there are things worse than a lost disk drive. I hope that my daughters -- who lost the most in our failure -- can feel this way, too. We are well on the way to resuming our digital lives, buoyed by technology that will help us not to suffer such a loss again.

That said, it's worth keeping in mind Jamie Zawinski's cautionary words, "the universe tends toward maximum irony", and stay alert.

Posted by Eugene Wallingford | Permalink | Categories: Personal

April 06, 2010 7:36 PM

Shame at Causing Loved Ones Harm

The universe tends toward maximum irony.
Don't push it.
-- JWZ

I have had Jamie Zawinski's public service announcement on backups sitting on desk since last fall. I usually keep my laptop and my office machine pretty well in sync, so I pretty much always have a live back-up. But some files live outside the usual safety zone, such as a temporary audio files on my desktop, which also contains one or two folders of stuff. I knew I need to be more systematic and complete in safeguarding myself from disk failure, so printed Zawinski's warning and resolved to Do the Right Thing.

Last week, I read John Gruber's ode to backups and disk recovery. This article offers a different prescription but the same message. You must be 100% backed up, including even the files that you are editing now in the minutes or hours before the next backup. Drives fail. Be prepared.

Once again, I was energized to Do the Right Thing. I got out a couple of external drives that I had picked out for a good price recently. The plan was to implement a stable, complete backup process this coming weekend.

The universe tends toward maximum irony. Don't push it.

If the universe were punishing me for insufficient respect for its power, you would think that the hard drive in either my laptop or my office machine would have failed. But both chug along just fine. Indeed, I still have never had a hard drive fail in any of my personal or work computers.

It turns out that the universe's sense of irony is much bigger than my machines.

On Sunday evening, the hard drive in our family iMac failed. I rarely use this machine and store nothing of consequence there. Yet this is a much bigger deal.

My wife lost a cache of e-mail, an address book, and a few files. She isn't a big techie, so she didn't have a lot to lose there. We can reassemble the contact information at little cost, and she'll probably use this as a chance to make a clean break from Eudora and POP mail and move to IMAP and mail in the cloud. In the end, it might be a net wash.

My teenaged daughters are a different story. They are from a new generation and live a digital life. They have written a large number of papers, stories, and poems, all of which were on this machine. They have done numerous projects for schools and extracurricular activities. They have created artwork using various digital tools. They have taken photos. All on this machine, and now all gone.

I cannot describe how I felt when I first realized what had happened, or how I feel now, two days later. I am the lead techie in our house, the computer science professor who knows better and preaches better, the husband and father who should be taking care of what matters to his family. This is my fault. Not that the hard drive failed, because drives fail. It is my fault that we don't have a reliable, complete backup of all the wonderful work my daughters have created.

Fortunately, not all is lost. At various times, we have copied files to sundry external drives and servers for a variety of reasons. I sometimes copy poetry and stories and papers that I especially like onto my own machines, for easy access. The result is a scattering of files here and there, across a half dozen machines. I will spend the next few days reassembling what we have as best I can. But it will not be all, and it will not be enough.

The universe maximized its irony this time around by getting me twice. First, I was gonna do it, but didn't.

That was just the head fake. I was not thinking much at all about our home machine. That is where the irony came squarely to rest.

Shut up. I know things. You will listen to me. Do it anyway.

Trust Zawinski, Gruber, and every other sane computer user. Trust me.

Do it. Run; don't walk. Whether your plan uses custom tools or a lowly cron running rysnc, do it now. Whether you go as far as using a service such as dropbox to maintain working files or not, set up an automatic, complete, and bootable backup of your hard drives.

I know I can't be alone. There must be others like me out there. Maybe you used to maintain automatic and complete system backups and for whatever reason fell out of the habit. Maybe you have never done it but know it's the right thing to do. Maybe, for whatever reason, you have never thought about a hard drive failing. You've been lucky so far and don't even know that your luck might change at any moment.

Do it now, before dinner, before breakfast. Do it before someone you love loses valuable possessions they care deeply about.

I will say this: my daughters have been unbelievable through all this. Based on what happened Sunday night, I certainly don't deserve their trust or their faith. Now it's time to give them what they deserve.

Posted by Eugene Wallingford | Permalink | Categories: Computing, Personal

March 12, 2010 9:49 PM

SIGCSE This and That, Volume 1

[A transcript of the SIGCSE 2010 conference: Table of Contents]

Day 2 brought three sessions worth their own blog entries, but it was also a busy day meeting with colleagues. So those entries will have to wait until I have a few free minutes. For now, here are a few miscellaneous observations from conference life.

On Wednesday, I checked in at the table for attendees who had pre-registered for the conference. I told the volunteer my name, and he handed me my bag: conference badge, tickets to the reception and Saturday luncheon, and proceedings on CD -- all of which cost me in the neighborhood of $150. No one asked for identification. I though, what a trusting registration.

This reminded me of picking up my office and building keys on my first day at my current job. The same story: "Hi, I'm Eugene", and they said, "Here are your keys." When I suggested to a colleague that this was perhaps too trusting, he scoffed. Isn't it better to work at a place where people trust you, at least until we have a problem with people who violate that trust? I could not dispute that.

The Milwaukee Bucks are playing at home tonight. At OOPSLA, some of my Canadian and Minnesotan colleagues and I have a tradition of attending a hockey game whenever we are in an NHL town. I'm as big a basketball fan as they are hockey fans, so maybe I should check out an NBA game at SIGCSE? The cheapest seat in the house is $40 or so and is far from the court. I would go if I had a posse to go with, but otherwise it's a rather expensive way to spend a night alone watching a game.

SIGCSE without my buddy Robert Duvall feels strange and lonely. But he has better things to do this week: he is a proud and happy new daddy. Congratulations, Robert!

While I was writing this entry, the spellchecker on my Mac flagged www.cs.indiana.edu and suggested I replace it with www.cs.iadiana.edu. Um, I know my home state of Indiana is part of flyover country to most Americans, but in what universe is iadiana an improvement?

People, listen to me: problem-solve is not a verb. It is not a word at all. Just say solve problems. It works just fine. Trust me.

Posted by Eugene Wallingford | Permalink | Categories: General, Personal

February 11, 2010 5:40 PM

Creativity and the Boldness of Youth

While casting about Roy Behrens's blog recently, I came across a couple of entries that connected with my own experience. In one, Behrens discusses Arthur Koestler and his ideas about creativity. I enjoyed the entire essay, but one of its vignettes touched a special chord with me:

In 1971, as a graduate student at the Rhode Island School of Design, I finished a book manuscript in which I talked about art and design in relation to Koestler's ideas. I mailed the manuscript to his London home address, half expecting that it would be returned unopened. To my surprise, not only did he read it, he replied with a wonderfully generous note, accompanied by a jacket blurb.

My immediate reaction was "Wow!", followed almost imperceptibly by "I could never do such a thing." But then my unconscious called my bluff and reminded me that I had once done just such a thing.

Back in 2004, I chaired the Educators' Symposium at OOPSLA. As I first wrote back then, Alan Kay gave the keynote address at the Symposium. He also gave a talk at the main conference, his official Turing Award lecture. The Educators' Symposium was better, in large part because we gave Kay the time he needed to say what he wanted to say.

2004 was an eventful year for Kay, as he won not only the Turing Award but also the Draper Prize and Kyoto Prize. You might guess that Kay had agreed to give his Turing address at OOPSLA, given his seminal influence on OOP and the conference, and then consented to speak a second time to the educators.

But his first commitment to speak was to the Educators' Symposium. Why? At least in part because I called him on the phone and asked.

Why would an associate professor at a medium-sized regional public university dare to call the most recent Turing Award winner on the phone and ask him to speak at an event on the undercard of a conference? Your answer is probably as good as mine. I'll say one part boldness, one part hope, and one part naivete.

All I know is that I did call, hoping to leave a message with his secretary and hoping that he would later consider my request. Imagine my surprise when his secretary said, "He's across the hall just now; let me get him." My heart began to beat in triple time. He came to the phone, said hello, and we talked.

For me, it was a marvelous conversation, forty-five minutes chatting with a seminal thinker in my discipline, of whose work I am an unabashed fan. We discussed ideas that we share about computer science, computer science education, and universities. I was so caught up in our chat that I didn't consider just how lucky I was until we said our goodbyes. I hung up, and the improbability of what had just happened soaked in.

Why would my someone of Kay's stature agree to speak at a second-tier event before he had even been contacted to speak at the main event? Even more, why would he share so much time talking to me? There are plenty of reasons. The first that comes to mind is most important: many of the most accomplished people in computer science are generous beyond my ken. This is true in most disciplines, I am sure, but I have experienced it firsthand many times in CS. I think Kay genuinely wanted to help us. He was certainly willing to talk to me at some length about my hopes for the symposium and the role he could play.

I doubt that this was enough to attract him, though. The conference venue being Vancouver helped a lot; Kay loves Vancouver. The opportunity also to deliver his Turing Award lecture at OOPSLA surely helped, too. But I think the second major reason was his longstanding interest in education. Kay has spent much of his career working toward a more authentic kind of education for our children, and he has particular concerns with the state of CS education in our universities. He probably saw the Educators' Symposium as an opportunity to incite revolution among teachers on the front-line, to encourage CS educators to seek a higher purpose than merely teaching the language du jour and exposing students to a kind of computing calcified since the 1970s. I certainly made that opportunity a part of my pitch.

For whatever reason, I called, and Kay graciously agreed to speak. The result was a most excellent keynote address at the symposium. Sadly, his talk did not incite a revolt. It did plant seeds in the minds of at least of a few of us, so there is hope yet. Kay's encouragement, both in conversation and in his talk, inspire me to this day.

Behrens expressed his own exhilaration "to be encouraged by an author whose books [he] had once been required to read". I am in awe not only that Behrens had the courage to send his manuscript to Koestler but also that he and Koestler continued to correspond by post for over a decade. My correspondence with Kay since 2004 has been only occasional, but even that is more than I could have hoped for as a undergrad, when I first heard of Smalltalk or, as a grad student, when I first felt the power of Kay's vision by living inside a Smalltalk image for months at a time.

I have long hesitated to tell this story in public, for fear that crazed readers of my blog would deluge his phone line with innumerable requests to speak at conferences, workshops, and private parties. (You know who you are...) Please don't do that. But for a few moments once, I felt compelled to make that call. I was fortunate. I was also a recipient of Kay's generosity. I'm glad I did something I never would do.

Posted by Eugene Wallingford | Permalink | Categories: Computing, General, Personal

January 17, 2010 7:50 PM

Humility and Aspiration

Time to blog has been scarce, with the beginning of an unusual semester. I am teaching two courses instead of one, and administrative surprises seem to be arriving daily, both inside the department and out. Teaching gives me energy, but most days I leave for home feeling a little humbler than I started -- or a little less satisfied with state of affairs.

Perhaps this is why a particular passage from an entry on urban planning policy at The Urbanophile keeps coming to mind. It offers a lesson for urban policy based on the author's reading of Dietrich Dörner's The Logic of Failure (a new addition to my must-read list):

The first [lesson] is simply to approach urban policy and urban planning with humility and rich understanding of the limits of what we can accomplish. This I think is desperately needed. There are so many policies out there that are promoted with almost messianic zeal by their advocates.

One person's messianic zeal, unfettered from reality, is a dangerous force. It can wear out even a resolute team; when coupled with normal human frailty, the results can destroy opportunities for progress.

Another passage from the same blog has had a more personal hold on me of late:

People with talent, with big dreams and ambitions, want to live in a place where the civic aspiration matches their personal aspirations.

Sense of place and sense of self are hard to separate. This is true for cities -- the great ones capitalize on the coalescence of individual and communal aspiration -- and for academic departments.

Posted by Eugene Wallingford | Permalink | Categories: Managing and Leading, Personal

January 08, 2010 4:34 PM

Courage and the Path to Greatness

Last spring, a colleague commented that he didn't think our department spent enough time trying to be great. This made me sad, but it struck me as true. At the time, I wasn't sure how to respond.

All groups have their internal politics. Some political situations are short-lived; others are persistent, endemic. We are no different, and maybe even above average. (Someone has to be!) Political struggles take time and energy. They steal focus.

I think everyone in our group desires to be great. Unfortunately, that's the easy part. For a group to achieve greatness, individuals must work together in a common direction. In our group, it is hard to build consensus on a shared vision. I don't pretend that once we share a vision that greatness will come easily, but it's hard to get anywhere unless everyone is trying to go to the same place -- or at least is using the same criteria for progress.

As for me, in my role as department head, I have not always found -- or created -- the will, the energy, or the tools I need to help us move confidently in the direction of greatness. So, at times, we seem to settle, working locally but not globally.

This train of thought reminds me of a couple of comments James Shore made about stumbling through mediocrity in the context of agile software development:

The emphasis [in the software world] has shifted from "be great" to "be Agile." And that's too bad. As much as I like it, there's really no point in Agile for the sake of Agile.

The point is to be great, or perhaps more accurately, to do great things. Agile approaches are a path, not a destination.

I want to work with people who want to be great. People who aren't satisfied just fitting in. People who are willing to take risks, rock the boat, and change their environment to maximize their productivity, throughput, and value.

One of the things that has surprised me so much about group dynamics since I joined a faculty and perhaps more so since I've been in the position of head is the enormous role that fear plays in how individuals work and interact with one another. It takes courage to take risks, to rock the boat, and to change the environment in which we live and work. It takes courage to be honest. It takes courage to take an action that may make a colleague or supervisor unhappy.

Without courage, especially at key moments, opportunities pass, sometimes before they are even recognized.

I have experienced this in how I interact with others, and occasionally I observe it how colleagues interact with me and others. I never thought that this would be a major obstacle on my path to greatness, or my department's.

(For what it's worth, Shore's second passage also describes the kind of students I like to work with, too. If it is hard for experienced adults to have this sort of gumption, imagine how much tougher an expectation it is to have of young people who are just learning how to step out into the world. Fortunately, as teachers, we have an opportunity to help students grow in this way.)

Posted by Eugene Wallingford | Permalink | Categories: Managing and Leading, Personal, Software Development

December 29, 2009 2:45 PM

Desks, Code, and Breaks

I've been enjoying time away from the office, classes, and even programming for the last week or so. After a long semester, spending time with my wife and daughters is just right.

It also gives me a chance to clean up my home office. What I am doing today is effectively refactoring: improving the structure of my stuff without adding any new capabilities. After this round of refactoring, I'll be ready to bring some new furniture in and do a couple of things I've been wanting to do since we moved in last December.

I won't strain the metaphor any farther, but I must say that my work day is a paradigm for this tweet by former student, musician, and software pro Chuck Hoffman:

"don't have time to refactor now" leads to "everything takes way more time because the code is confusing." The time gets spent either way.

True of code. True of papers piled high on a desktop or stacked in the corner of the room. In either world, you can pay now, or pay more later.

Posted by Eugene Wallingford | Permalink | Categories: Personal

December 09, 2009 8:14 PM

Perfection and Partial Order

Our town was hit with a blizzard over the last couple of days. Not only did it close the local schools, it even shut down my university -- a powerful storm, indeed.

I thought I might treat the day off as 'found time', and hack a little code I've been thinking about...

I feel a kinship with [Cormac McCarthy's] sense of a perfect day. To sit in a room, alone, with an open terminal. To write, whether prose or code, but especially code. (11/21/09)

... but I never wrote a line of code. Instead, I shoveled snow (a lot of snow). I wrote Christmas cards in the kitchen while my daughters baked cookies for their teachers. We listened to Christmas music and made chili and laughed.

Unlike McCarthy, I do not think that everything other than writing is a waste of time. Today was a perfect day.

Can there be two kinds of perfect day? Can there be different kinds of perfect? Indeed, there are multitudes. The sky is always a perfect sky, even as it changes from moment to moment.

We live in a world of partial order. There is no total ordering on experience.

Posted by Eugene Wallingford | Permalink | Categories: Personal

November 11, 2009 1:08 PM

Time Waits for No One

OR: for all p, eventually (modal)passed(p)


Last week saw the passing of computer scientist Amir Pnueli. Even though, Pnueli received the Turing Award, I do not have the impression that many computer scientists know much about his work. That is a shame. Pnueli helped to invent an important new sub-discipline of computing:

Pnueli received ACM's A. M. Turing Award in 1996 for introducing temporal logic, a formal technique for specifying and reasoning about the behavior of systems over time, to computer science. In particular, the citation lauded his landmark 1977 paper, "The Temporal Logic of Programs," as a milestone in the area of reasoning about the dynamic behavior of systems.

I was fortunate to read "The Temporal Logic of Programs" early in my time as a graduate student. When I started at Michigan State, most of its AI research was done in the world-class Pattern Recognition and Image Recognition lab. That kind of AI didn't appeal to me much, and I soon found myself drawn to the Design Automation Research Group, which was working on ways to derive hardware designs from specs and to prove assertions about the behavior of systems from their designs. This was a neat application area for logic, modeling, and reasoning about design. I began to work under Anthony Wojcik, applying the idea of modal logics to reasoning about hardware design. That's where I encountered the work of Pnueli, which was still relatively young and full of promise.

Classical propositional logic allows us to reason about the truth and falsehood of assertions. It assumes that the world is determinate and static: each assertion must be either true or false, and the truth value of an assertion never changes. Modal logic enables us to express and reason about contingent assertions. In a modal logic, one can assert "John might be in the room" to demonstrate the possibility of John's presence, regardless of whether he is or is not in the room. If John were known to be out of the country, one could assert "John cannot be in the room" to denote that it is necessarily true that he is not in the room. Modal logic is sometimes referred to as the logic of possibility and necessity.

These notions of contingency are formalized in the modal operators possibly (modal)p, "possibly p," and necessarily (modal)p, "necessarily p." Much like the propositional operators "and" and "or", possibly (modal) and necessarily (modal) can be used to express the other in combination with ¬, because necessity is really nothing more than possibility "turned inside out". The fundamental identities of modal logic embody this relationship:

modal identities

Modal logic extends the operator set of classical logic to permit contingency. All the basic relationships of classical logic are also present in modal logic. possibly (modal) and necessarily (modal) are not themselves truth functions but quantifiers over possible states of a contingent world.

When you begin to play around with modal operators, you start to discover some fun little relationships. Here are a few I remember enjoying:

modal relationships

The last of those is an example of a distributive property for modal operators. Part of my master's research was to derive or discover other properties that would be useful in our design verification tasks.

The notion of contingency can be interpreted in many ways. Temporal logic interprets the operators of modal logic as reasoning over time. necessarily (modal)p becomes "always p" or "henceforth p," and possibly (modal)p becomes "sometimes p" or "eventually p." When we use temporal logic to reason over circuits, we typically think in terms of "henceforth" and "eventually." The states of the world represent discrete points in time at which one can determine the truth value of individual propositions. One need not assume that time is discrete by its nature, only that we can evaluate the truth value of an assertion at distinct points in time. The fundamental identities of modal logic hold in this temporal logic as well.

In temporal logic, we often define other operators that have specific meanings related to time. Among the more useful temporal logical connectives are:

temporal logic operators

My master's research focused specifically on applications of interval temporal logic, a refinement of temporal logic that treats sequences of points in time as the basic units of reasoning. Interval logics consider possible states of the world from a higher level. They are especially useful for computer science applications, because hardware and software behavior can often be expressed in terms of nested time intervals or sequences of intervals. For example, the change in the state of a flip-flop can be characterized by the interval of time between the instant that its input changes and the instant at which its output reflects the changed input.

Though I ultimately moved into the brand-new AI/KBS Lab for my doctoral work, I have the fondest memories of my work with Wojcik and the DARG team. It resulted in my master's paper, "Temporal Logic and its Use in the Symbolic Verification of Hardware", from which the above description is adapted. While Pnueli's passing was a loss for the computer science community, it inspired me to go back to that twenty-year-old paper and reminisce about the research a younger version of myself did. In retrospect, it was a pretty good piece of work. Had I continued to work on symbolic verification, it may have produced an interesting result or two.

Postscript. When I first read of Pnueli's passing, I didn't figure I had a copy of my master's paper. After twenty years of moving files from machine to machine, OS to OS, and external medium to medium, I figured it would have been lost in the ether. Yet I found both a hardcopy in my filing cabinet and an electronic version on disk. I wrote the paper in nroff format on an old Sparc workstation. nroff provided built-in char sequences for all of the special symbols I needed when writing about modal logic that worked perfectly -- unlike HTML, whose codes I've been struggling with for this entry. Wonderful! I'll have to see whether I can generate a PDF document from the old nroff source. I am sure you all would love to read it.

Posted by Eugene Wallingford | Permalink | Categories: Computing, Personal

October 19, 2009 12:36 PM

An Off-Topic Musing about Love and Life

If you come hear to read only about computer science, software development, or teaching, then this entry probably isn't for you.

On Saturday, I attended the wedding of a family friend, the son of my closest friend from college. Some weddings inspire me, and this one did. I've been feeling a little jaded lately, and it was refreshing to see two wonderful young people, well-adjusted and good-hearted, starting a new chapter of life together.

During the minister's remarks to the bride and groom, I found myself thinking about love, and about big moments and little moments.

We often speak of one person loving another so much that he would lay down his life for her. That is a grand sort of love indeed. Many of our most romantic ideas about love come back to this kind of great personal sacrifice. It occurred to me that this is love in the big moment.

But how many of us are ever in a position where we must or even can demonstrate love in this way?

Nearly all of our chances to demonstrate love come in the nondescript moments that bathe us every day. These are not the big moments we dream of. We dream about big challenges, but the biggest challenge is to make small choices that demonstrate our love all the time. It is so easy for me to be selfish in the little desires that I act to satisfy daily. The real sacrifice is to surrender ourselves in those moments, to act in a way that puts another person, the one we love, at the front, to place her needs and wants ahead of our own.

When relationships falter, it is rarely because one person missed an opportunity to lay his life down -- literally. Much more often, it a result of small choices we make, of small sacrifices we could have made but didn't. I think that is one of the great sources of confusion for people whose at the end of relationships. They may well still be willing to lay down their loves for the loved one; what more could the other person want? It's hard to recognize all those little opportunities to sacrifice as they come by. How important they are.

The minister closed his remarks Saturday with a wish for the new couple that, at the end of long, happy lives together, they will be able to say, "I would choose you again." I make this wish for them, too. But I think one of the best ways to prepare for that distant moment is to wake up each day, say "I choose you" in the present tense, and then strive to live the little moments of that day well.

Posted by Eugene Wallingford | Permalink | Categories: Personal

September 29, 2009 5:51 PM

Life, Artificial and Oh So Real

Artificial. Tyler Cowen writes about a new arena of battle for the Turing Test:

I wonder when the average quality of spam comment will exceed the average quality of a non-spam comment.

This is not the noblest goal for AI, but it may be one for which the economic incentive to succeed drives someone to work hard enough to do so.

Oh So Real. I have written periodically over the last sixteen months about being sick with an unnamed and undiagnosed malady. At times, I was sick enough that I was unable to run for stretches of several weeks. When I tried to run, I was able to run only slowly and only for short distances. What's worse, the symptoms always returned; sometimes they worsened. The inability of my doctors to uncover a cause worried me. The inability to run frustrated and disappointed me.

Yesterday I read an essay by a runner about the need to run through a battle with cancer:

I knew, though, if I was going to survive, I'd have to keep running. I knew it instinctively. It was as though running was as essential as breathing.

Jenny's essay is at turns poetic and clinical, harshly realistic and hopelessly romantic. It puts my own struggles into a much larger context and makes them seem smaller. Yet in my bones I can understand what she means: "... that is why I love running: nothing me feel more alive. I hope I can run forever."

Posted by Eugene Wallingford | Permalink | Categories: Computing, Personal, Running

September 14, 2009 10:53 PM

Old Dreams Live On

"Only one, but it's always the right one."
-- Jose Raoul Capablanca,
when asked how many moves ahead
he looked while playing chess

When I was in high school, I played a lot of chess. That's also when I first learned about computer programming. I almost immediately was tantalized by the idea of writing a program to play chess. At the time, this was still a novelty. Chess programs were getting better, but they couldn't compete with the best humans yet, and I played just well enough to know how hard it was to play the game really well. Like so many people of that era, I thought that playing chess was a perfect paradigm of intelligence. It looked like such a wonderful challenge to the budding programmer in me.

I never wrote a program that played chess well, yet my programming life often crossed paths with the game. My first program written out of passion was a program to implement a ratings system for our chess club. Later, in college, I wrote a program to perform the Swiss system commonly used to run chess tournaments as a part of my senior project. This was a pretty straightforward program, really, but it taught me a lot about data structures, algorithms, and how to model problems.

Though I never wrote a great chessplaying program, that was the problem that mesmerized me and ultimately drew me to artificial intelligence and a major in computer science.

In a practical sense, chess has been "solved", but not in the way that most of us who loved AI as kids had hoped. Rather than reasoning symbolically about positions and plans, attacks and counterattacks, Deep Blue, Fritz, and all of today's programs win by deep search. This is a strategy that works well for serial digital computers but not so well for the human mind.

To some, the computer's approach seems uncivilized even today, but those of us who love AI ought be neither surprised nor chagrined. We have long claimed that intelligence can arise from any suitable architecture. We should be happy to learn how it arises most naturally for machines with fast processors and large memories. Deep Blue's approach may not help us to understand how we humans manage to play the game well in the face of its complexity and depth, but it turns out that this is another question entirely.

Reading David Mechner's All Systems Go last week brought back a flood of memories. The Eastern game of Go stands alone these days among the great two-person board games, unconquered by the onslaught of raw machine power. The game's complexity is enormous, with a branching factor at each ply so high that search-based programs soon drown in a flood of positions. As such, Go encourages programmers to dream the Big Dream of implementing a deliberative, symbolic reasoner in order to create a programs that plays the game well. The hubris and well-meaning naivete of AI researchers have promised huge advances throughout the years, only to have ambitious predictions go unfulfilled in the face of unexpected complexity. Well-defined problems such as chess turned out to be complex enough that programs reasoning like humans were unable to succeed. Ill-defined problems involving human language and the interconnected network of implicit knowledge that humans seem to navigate so easily -- well, they are even more resistant to our solutions.

Then, when we write programs to play games like chess well, many people -- including some AI researchers -- move the goal line. Schaefer et al. solved checkers with Chinook, but many say that its use of fast search and a big endgame databases is unfair. Chess remains unsolved in the formal sense, but even inexpensive programs available on the mass market play far, far better than all but a handful of humans in the world. The best program play better than the best humans.

Not so with Go. Mechner writes:

Go is too complex, too subtle a game to yield to exhaustive, relatively simpleminded computer searches. To master it, a program has to think more like a person.

And then:

Go sends investigators back to the basics--to the study of learning, of knowledge representation, of pattern recognition and strategic planning. It forces us to find new models for how we think, or at least for how we think we think.

Ah, the dream lives!

Even so, I am nervous when I read Mechner talking about the subtlety of Go, the depth of its strategy, and the impossibility of playing it well in by search and power. The histories of AI and CS have demonstrated repeatedly that what we think difficult often turns out to be straightforward for the right sort of program, and that what we think easy often turns out to be achingly difficult to implement. What Mechner calls 'subtle' about Go may well just be a name for our ignorance, for our lack of understanding today. It might be wise for Go aficionados to remain humble... Man's hubris survives only until the gods see fit to smash it.

We humans draw on the challenge of great problems to inspire us to study, work, and create. Lance Fortnow wrote recently about the mystique of the open problem. He expresses the essence of one of the obstacles we in CS face in trying to excite the current generation of students about our discipline: "It was much more interesting to go to the moon in the 60's than it is today." P versus NP may excite a small group of us, but when kids walk around with iPhones in their pockets and play on-line games more realistic than my real life, it is hard to find the equivalent of the moon mission to excite students with the prospect of computer science. Isn't all of computing like Fermat's last theorem: "Nothing there left to dream there."?

For old fogies like me, there is still a lot of passion and excitement in the challenge of a game like Go. Some days, I get the urge to ditch my serious work -- work that matters to people in the world, return to my roots, and write a program to play Go. Don't tell me it can't be done.

Posted by Eugene Wallingford | Permalink | Categories: Computing, Personal

July 28, 2009 12:40 PM

CS in Everything: On the Hardwood

The economics blog Marginal Revolution has an occasional series of posts called "Markets in Everything", in which the writers report examples of markets at work in various aspects of everyday life. I've considered doing something similar here with computing, as a way to document some concrete examples of computational thinking and -- gasp! -- computer programs playing a role how we live, work, and play. Perhaps this will be a start.

Courtesy of Wicked Teacher of the West, I came across this story about NBA player Shane Battier, who stands out in an unusual way: by not standing out with his stats. A parallel theme of the story is how the NBA's Houston Rockets are using data and computer analysis in an effort to maximize their chances of victory. The connection to Battier is that the traditional statistics we associate with basketball -- points, rebounds, assists, blocked shots, and the like -- do not reflect his value. The Rockets think that Battier contributes far more to their chance of winning than his stat line shows.

The Rockets collect more detailed data about players and game situations, and Battier is able to use it to maximize his value. He has developed great instincts for the game, but he is an empiricist at heart:

The numbers either refute my thinking or support my thinking, and when there's any question, I trust the numbers. The numbers don't lie.

For an Indiana boy like myself, nothing could be more exciting than knowing that the Houston Rockets employ a head of basketball analytics. This sort of data analysis has long been popular among geeks who follow baseball, a game of discrete events in which the work of Bill James and like-minded statistician-fans of the American Pastime finds a natural home. I grew up a huge baseball fan and, like all boys my age, lived and died on the stats of my favorite players. But Indiana is basketball country, and basketball is my first and truest love. Combining hoops with computer science -- could there be a better job? There is at least one guy living the dream, in Houston.

I have written about the importance of solving real problems in CS courses, and many people are working to redefine introductory CS to put the concepts and skills we teach into context. Common themes include bioinformatics, economics, and media computation. Basketball may not be as important as sequencing the human genome, but it is real and it matters to a enough people to support a major entertainment industry. If I were willing to satisfy my own guilty pleasures, I would design a CS 1 course around Hoosier hysteria. Even if I don't, it's comforting to know that some people are beginning to use computer science to understand the game better.

Posted by Eugene Wallingford | Permalink | Categories: Computing, Personal, Teaching and Learning

May 12, 2009 4:22 PM

Surprises, Problems, and Small Aircraft

Earlier today I listened to a TED talk by Tony Robbins. One snippet stood out. Here is a paraphrase, in part to clean up the language (because that's how I roll):

If I ask you whether you like variety, you'll say yes. Baloney. You like surprises you want. The others, you call problems.

Some people are better than others at accepting the surprises that they don't want. Perhaps that is why Robbins's anecdote reminded me of a story I read last summer in a book by John G. Miller called QBQ! The Question Behind the Question. The story, perhaps fictional, tells of a father and young daughter out for a fun plane ride one day, with dad behind the controls. When the plane's engine dies unexpectedly, dad turns to his daughter and says, calmly, I'm going to need to fly the plane differently.

I don't make generally New Year's resolutions, but when I am next tempted, I'll probably think again of this story. I want to be that guy, and I'm not.


(Quick book review: QBQ! is pretty standard for this genre of business self-help lit. It says a lot of things we all should already know, and probably do. But there are days when some of us need a reminder or a little pep talk. This book is full of short pep talks. It's a quick read and good enough at its task, as long as you remember that unless you change your behavior books like these are nothing but empty calories. A bit like software design methodologies.)

Posted by Eugene Wallingford | Permalink | Categories: Personal, Software Development

May 04, 2009 7:59 AM

Best Case Scenario

My expectations for the 500 Festival Mini-Marathon were rather low. I've been battling subpar health for a year, so my mileage has been down. I've gone through a few dry stretches of six to eight weeks without running much or at all.. I've been running again for the last ten weeks or so, but I've managed only to reach the mid-twenties of miles in any given week. My body just isn't ready for running many miles, let alone racing them.

My running buddy, Greg, and I arrived in downtown Indianapolis half an hour before the start time of the race. It was overcast and cool -- around 47 degrees -- with the slightest of breezes. I cast my lot with the possibility that we'd not run in the rain and left my cap in my checked back, but I did throw on my thinnest pair of gloves. A good choice.

When you run with 35,000 other runners, the start of a race is always a little crowded. After the official start of the race, Greg and I shuffled along for six and half minutes before we reached the starting line. From that point, we ran in tight traffic for only a third of a mile or so before we could move unencumbered. I was how quickly that moment came. I was also surprised at the pace of our first couple of miles. Even with the shuffling start we clocked a 9:08 for Mile 1, and then we did Mile 2 in 8:37. I won't be able to keep this up for much longer, I said, so don't feel bad about leaving me behind. But I didn't feel as if I were pressing, so I hung steady.

Talking as we ran helped me stay steady. I have gone to races with Greg and other friends before, but I have never actually run with them. We spend time together before and after the race, but during we find our own strides and run our own races. This time, we actually ran together. The miles clicked off. 8:33. 8:32. Can this be? 8:42. Ah, a little slower.

The we reached the famed Indianapolis Motor Speedway, home to the 500 mile race that gives its name to the race I am running. Race cars navigate this brick and asphalt oval in 40 seconds, but thousands of runners staked their claims in anywhere from twelve minutes to over an hour. We saw the 6-, 7-, and 8-mile markers inside the track, along with the 10K split and the halfway point. 8:46. 8:49. 8:44. Slower, yet hanging steady.

I felt a slight tug in my left calf just before the 9-mile marker. I did not mention it out loud, because I did not want to make it real. We kept talking, and I kept moving. 8:46. 8:29. What? 8:29?? The tenth mile was our fastest yet. I felt good -- not "just getting started" strong, but "I can keep doing this" strong. I thought of Barney Stinson's advice and just kept running.

I took a last sip of fuel just past the 10-mile mark. 8:22. Greg and I decided that we would let ourselves really run the last mile if we still felt good. We must have. We clipped off miles 12 and 13 in 16:16. Then came that last mad rush to the finish line. 1:52:25. I have never been so happy to run my second worst time ever. This was 8-10 minutes faster than I imagined I could run, and I finished strong, thinking I could do a little more if I had to. (Not another half, of course -- I am nowhere near marathon shape!)

Talking throughout the race definitely helped me. It provided a distraction from the fact that we were running hard, that the miles were piling up behind us. I never had a chance for my mind to tell I couldn't do what I was doing, because it didn't have a chance to focus on the distance. Our focus was on the running, on the moment. We took stock of each mile as a single mile and then took on the current mile. In an odd way, it was a most conscious race.

The only ill effect I have this morning is a barely sore left hamstring that gave its all for those last two mile and a minor headache. In all other ways I feel good and look forward to hitting the trails tomorrow morning with another challenge in mind.

The weekend itself was not an uninterrupted sequence of best case scenarios... As I pulled out of the parking garage after picking up my race packet in downtown Indianapolis, my car began gushing coolant. Was there any irony in the fact that I was at that moment listening to Zen and the Art of Motorcycle Maintenance? I am not one of those guys who tinkers with his own engine, but I know enough to know that you can't go far without coolant.

Still, I did not face a worst case scenario. I called the friend with whom I was to dine that night, and he came to get me. He arranged for a tow, and while I ran on Saturday morning a professional who knows his way around under the hood fixed the problem -- a faulty reservoir -- for only a couple of hundred dollars. Given the circumstances, I could hardly have asked for a better resolution.

Race day, May 2, was one year to the day of my last 100% healthy work-out... I do not think I am yet 100% healthy again, and I did not finish the half marathon with Ernie Banks's immortal words on my lips ("Let's play two!". But I have to say: Great day.

Posted by Eugene Wallingford | Permalink | Categories: Personal, Running

April 02, 2009 6:47 AM

Too Much a Computer Scientist

You are scanning a list of upcoming lectures on campus.

You see the title "Media Manipulation".

You get excited! Your thoughts turn to image rotations and filters, audio normalization and compression formats.

You read on to see the subtitle: "You, Me, and Them (the 'media' isn't what it used to be)" and realize that the talk isn't about CS; it's about communications and journalism.

You are disappointed.


(I'd probably enjoy this talk anyway... The topic is important, and I know and like the speaker. But still. To be honest, in recent weeks I have been less concerned with the media manipulating me than with the people in the media not doing the research they need to ensure their stories are accurate.)

Posted by Eugene Wallingford | Permalink | Categories: Personal

March 18, 2009 8:01 AM

Setting a Good Example

David Patterson wrote a Viewpoint column for the March 2009 issue of Communications on advising graduate students, paired with a column by Jeffrey Ullman. One piece of Patterson's advice applies to more than advising grad students: "You're a role model; act like one.":

I am struck from parenting two now-grown sons that it's not what you say but what you do that has lasting impact. I bet this lesson applies to your academic progeny. Hence, I am conscious that students are always watching what I do, and try to act in ways that I'd like them to emulate later.

For example, my joy of being a professor is obvious to everyone I interact with, whereas I hear that some colleagues at competing universities complain to their students how hectic their lives are.

I often worry about the message I send students in this regard. My life is more hectic and less fun with computer science since I became department head, and I imagine that most of the negative vibe I may give off is more about administration than academia. One time that I am especially careful about the image I project is when I meet with high school students who are prospective CS majors and their parents. Most of those encounters are scheduled in advance, and I can treat them almost like performances. But my interactions with current students on a daily basis? I'm probably hit-and-miss.

The idea that people will infer more from your deeds than your words is not new and does apply widely, to advisors, teachers, decision makers -- everyone, really. Anyone who has been a parent knows what Patterson means about having raised his sons. Long ago I marked this passage from Matthew Kelly's Building Better Families:

If you ask parents if they want their children to grow up to live passionate and purposeful lives they will say, "Absolutely!" But how many parents are living passionate and purposeful lives? Not so many.

Our example can set a negative tone or a positive tone. The best way to give children a zest for life is to live with zest and share your zest with them.

This applies to our students in class and in the research lab, too. My favorite passage in this regard comes not from Patterson's viewpoint but from The Wednesday Wars, which I quoted once before:

It's got to be hard to be a teacher all the time and not jump into a pool of clear water and come up laughing and snorting with water up your nose.

Through all my years in school, my best teachers jumped into the pool all the time and came up laughing and snorting with water up their noses. They wrote prose and code. They read about new ideas and wanted to try them out in the lab. Their excitement was palpable. Fun was part of the life, and that's what I wanted.

I hope I can embody a little of that excitement and fun as a faculty member to our students, as a father to my daughters. But some days, that is more of a challenge than others.

Posted by Eugene Wallingford | Permalink | Categories: Personal, Teaching and Learning

March 16, 2009 3:41 PM

Imbued With The Spirit Of YAGNI

I spent most of the last four days of last week -- and nights -- digging out of the result of having lived 17 years in one house, as a moderate pack rat living with three major pack rats.

Remember that whole moving agile thing? Fuhgeddaboudit. The idea worked well for a few weeks. But then we encountered a problem everyone knows to avoid: the developers were the same people as the customers. When we got somewhere between 60% and 80% of our stuff moved, we reached something akin to a software prototype that offers most of the desired features. At that point, the customers went inexplicably AWOL. They were happy enough with the 80% solution.

Then came a long period of no measurable progress, no external motivation, and no Big Visible Chart to keep the developers honest.

Finally came the week of the closing on the sale of the old house. We were exceedingly lucky to have found buyers the first day the house was on the market and to have them want to close in a brisk five weeks. Hurray! ... except for the part about moving the rest of our stuff. We found ourselves in horrible crunch mode. The last 20% took 80% of the total move time. I worked around the clock for four days, stopping for classes and essential meeting. In the end, we just made it -- I, dead tired, with a bad cold, and a lot of stuff in boxes.

Why the title? After 17 years of saving things we "might need some day", we know the answer. We never did. We had boxes. Packing material. Textbooks, class notes. YAGNI. Really. I went from sentimental fool having a hard time tossing anything to pitching favored gifts and keepsakes like a disinterested pro. A few possessions rose above the newly-elevated threshold for what to keep, but not many. If I don't have a specific plan for using something in the next few weeks, it is gone. I have enough boxes and portfolios and a pile of notebooks and pads sufficient to outfit a medium-sized government agency. If I don't have a specific scenario for reminiscing over some memento, it too is gone. Sportsmanship trophies from 2nd-grade basketball leagues? I don't think so.

I ain't gonna need it. I trust that now. This is the best lesson for living more simply than I've ever received.

Posted by Eugene Wallingford | Permalink | Categories: Personal

March 06, 2009 8:01 PM

Coming Up For Air

I have spent nearly every working minute this week sitting in front of this laptop, preparing a bunch of documents for an "academic program assessment" that is being done campus-wide at my university. Unfortunately, that makes this week Strike Two.

Last October: no OOPSLA for me.

This week: no SIGCSE for me.

The next pitch arrives at the plate in about a month... Will there be no ChiliPLoP for me?

That would be an inglorious Strike Three indeed. It would break my equivalent of DiMaggio's streak: I have never missed a ChiliPLoP. But budget rescissions, out-of-state travel restrictions, and work, work, work are conspiring against me. I intend to make my best effort. Say a little prayer.

I hope that you can survive my missing SIGCSE, as it will mean no reports from the front. Of course, you will notice two missing links on my 2008 report, so I do have some material in the bullpen!

Missing SIGCSE was tougher than usual, because this year I was to have been part of the New Teaching Faculty Roundtable on the day before the conference opened. I was looking forward to sharing what little wisdom I have gained in all my years teaching -- and to stealing as many good ideas as I could from the other panelists. Seeing all of the firepower on the roster of mentors, I have no doubts that the roundtable was a great success for the attendees. I hope SIGCSE offers the roundtable again next year.

Part of my working day today was spent in Cedar Rapids, an hour south of here. Some of you may recall that Cedar Rapids was devastated by flooding last summer, when much of the eastern part of the state was under 500-year flood waters. I surprised and saddened to see that so much of the downtown area still suffers the ill effects of the water. The public library is still closed while undergoing repair. But I was heartened to see a vibrant city rebuilding itself. A branch library has been opened at a mall on the edge of town, and it was buzzing with activity.

You know, having a library in the mall can be a good thing. It is perhaps more a part of some people's lives than a dedicated building in the city, and it serves as a nice counterpoint to the consumption and noise outside the door. Besides, I had easy access to excellent wireless service out in mall area even before the library opened, and easy access to all the food I might want whenever I needed to take a break. Alas, I really did spend nearly every working minute this week sitting in front of this laptop, so I worked my way right up to dinner time and a welcome drive home.

Posted by Eugene Wallingford | Permalink | Categories: General, Personal

January 26, 2009 7:52 PM

Our Gods Die Hard

Many of us know this feeling:

When gods die, they die hard. It's not like they fade away, or grow old, or fall asleep. They die in fire and pain, and when they come out of you, they leave your guts burned. It hurts more than anything you can talk about. And maybe worst of all is, you're not sure if there will ever be another god to fill their place. You don't want the fire to go out inside you twice.

I'm tempted to say that the urge to share this came from a couple of experiences I had at the Rebooting Computing summit, but this passage goes beyond the emotions I felt there.

(This paragraph comes from a "young adult" novel called the The Wednesday Wars, by Gary D. Schmidt. I did not realize how many good books there are out there for young readers until my daughters started reading them and recommending them to me. If there is a book that can make Shakespeare more relevant to the life of a seventh-grader or more attractive for a teen to read than this one -- all the while being funny and on the mark for its audience -- I'd love to read it.)

Posted by Eugene Wallingford | Permalink | Categories: Personal

December 31, 2008 4:06 PM

Ending an Unusual Month and Year

This has been an unusual year in several ways. This month ends it fittingly, in an unusual way: my fewest ever postings to this blog in any calendar month since its inception. I have nor blogged much this month for a couple of reasons. The first is that I have tried to make my break time a break, and so have stayed away from my computer more than usual.

The second is less sedentary. My family bought a new house this month. We made an initial offer in October, worked through a lot of details and last-stage construction issues in November, and closed in early December. The last few weeks have been a combination of finishing fall term, tryine to rest a bit, and moving a car- or minivan-load at a time. Moving over the course of several weeks is how my wife and I planned to do it. Baby steps is an interesting way to move, as we grow into each space a bit at a time, with time to think before being buried in boxes labeled "downstairs bedroom". I am still enjoying it and seeing the advantages of it (not the least of which is time to throw out all of the stuff we don't want to move!), but I think it is starting to tire my family. They would like to be "moved". Come to think of it, so would I. It's about time to bring this iteration to a close.

Happy New Year to all.

Posted by Eugene Wallingford | Permalink | Categories: Personal

December 30, 2008 9:47 AM

Feeling Incompetent

My daughters received a new game from their mom for Christmas. It's called Apples to Apples. Each round, one of the players draws a card with an adjective on it. The rest of the players choose noun cards from their hands that match the adjective. The judge chooses one of the nouns as the best match, and the player who played it wins that round. The objective of the game is to win the most rounds.

I could tell you many things more about the game and how it's played in my family, but there is really only one thing to say:

I stink at this game.

If I am in a three-person game, I finish third. Four players? Fourth. You name the number of players, and I can tell you where I'll finish. Last.

It doesn't seem to matter with whom I play. Recently, I've been playing with my wife and daughters. Last night, my wife's brother joined us. My wife and I have played this game before, with friends from my office. The result is always the same.

My weakness may be heightened by the lobbying that can be part of the game. Players are allowed to try to sell their answers to the judge. I'm not a good salesman and besides don't really like to sell. But that doesn't account for my losing. If we play in silence, I lose.

It's not that I'm bad at all word games. I like many word games and generally do well playing them. If nothing else, I get better after I play a game for a while, by figuring out something about the strategy of the game and the players with whom I play. But in this game, the harder I try to play well, the worse I seem to do.

This must be how students feel in class sometimes. There is some consolation -- that I might become more empathetic as a result of feeling this way -- but, to be honest, it's just a bad feeling.

Posted by Eugene Wallingford | Permalink | Categories: Personal, Teaching and Learning

December 11, 2008 7:37 AM

Movin' Out, Twyla Tharp, and Inspiration

a scene from the Broadway musical Movin' Out

Last month my wife and I had the good fortune to see a Broadway touring company perform the Tony Award-winning Movin' Out, a musical created by Twyla Tharp from the music of Billy Joel. I've already mentioned that I am a big fan of Billy Joel, so the chance to listen to his songs for two hours was an easy sell. Some of you may recall that I also wrote an entry way back called Start with a Box that was inspired by a wonderful chapter from Twyla Tharp's The Creative Habit. So even if I knew nothing else about Tharp, Movin' Out would have piqued my interest.

This post isn't about the show, but my quick review is: Wow. The musicians were very good -- not imitating Joel, but performing his music in a way that felt authentic and alive. (Yes, I sang along, silently to myself. My wife said she saw my lips moving!) Tharp managed somehow to tell a compelling story by stitching together a set of unrelated songs written over the long course of Joel's career. I know all of these songs quite well, and occasionally found myself thinking, "But that's not what this song means...". Yet I didn't mind; I was hearing from within the story. And I loved the dance itself -- it was classical even when modern, not abstract like Merce Cunningham's Patterns in Space and Sound. My wife knows dance well, and she was impressed that the male dancers in this show were actually doing classical ballet. (In many performances, the men are more props than dancers, doing lifts and otherwise giving the female leads a foil for their moves.)

Now I see that Merlin Mann is gushing over Tharp and The Creative Habit. Whatever else I can say, Mann is a great source of links... He points us to a YouTube video of Tharp talking about "failing well", as well as the first chapter of her book available on line. Now you can read a bit to see if you want to bother with the whole book. I echo Mann's caveat: we both liked the first chapter, but we liked the rest of the book more.

Since my post three years ago on The Creative Habit, I've been meaning to return to some of the other cool ideas that Tharp writes about in this book. Seeing Movin' Out caused me to dig out my notes from that summer, and seeing Mann's posts has awakened my desire to write some of the posts I have in mind. The ideas I learned in this book relate well to how I write software, teach, and learn.

Here is a teaser that may connect with agile software developers and comfort students preparing for final exams:

The routine is as much a part of the creative process as the lightning bolt of inspiration, maybe more. And this routine is available to everyone.

Oddly, this quote brings to mind an analogy to sports. Basketball coaches often tell players not to rely on having a great shooting night in order to contribute to the team. Shooting is like inspiration; it comes and it goes, a gift of capricious gods. Defense, on the other hand, is always within the control of the player. It is grunt work, made up of effort, attention, and hustle. Every player can contribute on defense every night of the week.

For me, that's one of the key points in this message from Tharp: control what you can control. Build habits within which you work. Regular routine -- weekly, daily, even hourly -- are the scaffolding that keep you focused on making something. What's better, everyone can create and follow a routine.

While I sit and wait for the lightning bolt of inspiration to strike, I am not producing code, inspired or otherwise. Works of inspiration happen while I am working. Working as a matter of routine increases the chances that I will be producing something when the gods smile on me with inspiration. And if they don't... I will still be producing something.

Posted by Eugene Wallingford | Permalink | Categories: General, Personal, Teaching and Learning

November 30, 2008 10:04 PM

Disconnected Thoughts to End the Month

... and a week of time away from work and worries.

There is still something special about an early morning run on fresh snow. The world seems new.

November has been a bad month for running, with my health at its lowest ebb since June, but even one three-mile jog brings back a good feeling.

I can build a set of books for our home finances based on the data I have at hand. I do not have to limit myself to the way accountants define transactions. Luca Pacioli was a smart guy who did a good thing, but our tools are better today than they were in 1494. Programs change things.

S-expressions really are a dandy data format. They make so many things straightforward. Some programmers may not like the parens, but simple list delimiters are all I need. Besides, Scheme's (read) does all the dirty work parsing my input.

After a week's rest, I imagine something like one of those signs from God:

That "sustainable pace" thing...
I meant that.

-- The Agile Alliance

I'd put Kent or Ward's name in there, but that's a lot of pressure for any man. And they might not appreciate my sense of humor.

The Biblical story of creation in six days (small steps) with feedback ("And he saw that it was good.") and a day of rest convinces me that God is an agile developer.

Posted by Eugene Wallingford | Permalink | Categories: General, Personal

October 29, 2008 9:16 AM

Clearing the Mind for a Trip

I leave today to attend the second SECANT workshop at Purdue. This is the sort of trip I like: close enough that I can drive, which bypasses all the headaches and inconveniences of flight, but far enough away that it is a break from home. My conference load has been light since April, and I can use a little break from the office. Besides, the intersection of computer science and the other sciences is an area of deep interest, and the workshop group is a diverse one. It's a bit odd to look forward to six hours on the road, but driving, listening to a book or to music, and thinking are welcome pursuits.

As I was checking out of the office, I felt compelled to make two public confessions. Here they are.

First, I recently ran across another recommendation for Georges Perec's novel, Life: A User's Manual. This was the third reputable recommendation I'd seen, and as is my general rule, after the third I usually add it to my shelf of books to read. As I was leaving campus, I stopped by the library to pick it up for the trip. I found it in the stacks and stopped. It's a big book -- 500 pages. It's also known for its depth and complexity. I returned the book to its place on the shelf and left empty-handed. I've written before of my preference for shorter books and especially like wonderful little books that are full of wisdom. But these days time and energy are precious enough resources that I have to look at a complex, 500-page book with a wary eye. It will make good reading some other day. I'm not proud to admit it, but my attention span isn't up to the task right now.

Second, on an even more frivolous note, there is at the time of this writing no Diet Mountain Dew in my office. I drank the last one yesterday afternoon while giving a quiz and taking care of pre-trip odds and ends. This is noteworthy in my mind only because of its rarity. I do not remember the last time the cupboard was bare. I'm not a caffeine hound like some programmers, but I don't drink coffee and admit some weakness for a tasty diet beverage while working.

I'll close with a less frivolous comment, something of a pattern I've been noticing in my life. Many months ago, I wrote a post on moving our household financial books from paper ledgers and journals into the twentieth century. I fiddled with Quicken for a while but found it too limiting; my system is a cross between naive home user and professional bookkeeping. Then I toyed with the idea of using a spreadsheet tool like Numbers to create a cascaded set o journals and ledgers. Yet at every turn I was thinking that I'd want to implement this or that behavior, which would strain the limits of typical spreadsheets. Then I came to my computer scientist's senses: When in doubt, write a program. I'd rather spend my time that way anyway, and the result is just what I want it to be. No settling. This pattern is, of course, no news at all to most of you, who roll your own blogging software and homework submission systems, even content management systems and book publishing systems, to scratch your own itches. It's not news to me, either, though sometimes my mind comes back to the power slowly. The financial software will grow slowly, but that's how I like it.

As a friend and former student recently wrote, "If only there were more time..."

Off to Purdue.

Posted by Eugene Wallingford | Permalink | Categories: General, Personal

August 19, 2008 1:21 PM

A Lost Summer

For the last five years, mid-August has meant more than getting ready for fall semester. It has meant 50+ mile weeks. It has meant once or twice weekly track workouts. It has meant hours each week running, before dawn in cool, moist air; in newly-risen sunlight; in the rain.

A month ago I was still figuring things out about my running, hoping to get well all the while. Unfortunately, I haven't gotten well. At times, I have gotten better, but never well, and punctuated every couple of weeks by a return of the same symptoms that have dogged me since May 2. I've been running since early June, because I wasn't getting better anyway. The last month or two, I have managed between 24 and 29 miles each week, with one 31.5-mile week that left tired for a week afterwards. Many people think that 25-30 mile weeks are awesome, but for me they aren't, and all the while I'm looking to get better.

My doctor is baffled. He has run every test he can imagine, and all he and his nurses can say is, man, you are healthy. That's good news! ... except for the part of not being well.

We'll keep looking, and I'll keep plodding along. But I really miss the summer of running I didn't have. August isn't quite the same.

Posted by Eugene Wallingford | Permalink | Categories: Personal, Running

July 05, 2008 9:57 PM

Wedding Season

On my way into a store this afternoon to buy some milk, I ran into an old friend. He moved to town a decade or so ago and taught art at the university for five years before moving on to private practice. As we reminisced about his time on the faculty, we talked about how much we both like working with students. He mentioned that he recently attended his 34th wedding of a former student.

Thirty-four weddings from five years of teaching. I've been teaching for sixteen years and have been invited to only a handful of weddings -- three or four.

Either art students are a different lot from CS students, or I am doing something wrong...

Posted by Eugene Wallingford | Permalink | Categories: General, Personal

June 23, 2008 3:56 PM

Home Alone

I have been home alone with my daughters for the last few days. It's always neat to have the chance to talk with the girls over an extended time, because they do say some amazing things.

Over lunch a few days ago, we were talking about classes at school. I had been telling them about Lockhart's Lament, which I had just started reading. (More on that later.) Our conversation turned to art class, and how some teachers don't seem to understand what it means to create art. One teacher always told the students to keep things simple, because then they would get done faster. My younger daughter couldn't hide her exasperation. "She doesn't understand. It's not about fastest; it's about masterpieces." That bit of wisdom reminded me why I know she will do good things in her life.

My puffed-up pride didn't last long. The next day, in the course of a conversation I've already forgotten otherwise, she told me, "It's not that you're old, Dad; you're just too old." That's too much truth for me.

Sometimes the girls like my relatively advanced age. Over the weekend, they pulled my old Trivial Pursuit game off the shelf, and we had several hours of fun. I love that they've already read enough in their short lives to be able to play the game pretty well, and that they enjoy spending an evening or two trading questions and answers with their old dad.

Posted by Eugene Wallingford | Permalink | Categories: Personal

June 13, 2008 3:08 PM

Sweet Dreams, Friday Afternoon Edition

Here I am, sitting in the office on a quiet Friday afternoon, looking forward to the weekend and writing up a short blog entry on a couple of cool software patterns. In another window is playing the WWDC 2008 keynote talk.

Suddenly, my ears hear the soothing voice of Steve Jobs say:

Imagine you are a university professor and you are teaching a class in how to write iPhone apps.

Writing code. An iPhone. Teaching class. Sweet Dreams (are made of this).

Back to work.

Posted by Eugene Wallingford | Permalink | Categories: Personal

June 12, 2008 9:53 PM

The Subject of My Writing

In recent days, I have written about not reading books and the relationship of these ideas to writing, from my enjoyment of Pierre Bayard's How to Talk About Books You Haven't Read. A couple of readers have responded with comments about how important reading is. Don't worry -- much of what Bayard and I are saying here is a joke. But it is also true, when looked at with one's head held tilted just so, and that's part of what made the book interesting to me. For you software guys, think about Extreme Programming -- an idea taken to its limits, to see what the limits can teach us. You can be sure that I am not telling you not to read every line of every novel and short story by Kurt Vonnegut! (I certainly have, some many, many times, and I enjoyed every minute.) Neither is Bayard, though it may seem so sometimes.

In my entries inspired by the book, it seems as if I am talking about myself an awful lot. Or consider my latest article, on parsing in CS courses. I read an article by Martin Fowler and ended up writing about my course and my opinions of CS courses. My guess is that most folks out there are more interested in Fowler's ideas than mine, yet I write.

This is another source of occasional guilt... Shouldn't this blog be about great ideas? When I write about, say, Bayard's book, shouldn't the entry be about Bayard's book? Or at least about Bayard?

Bayard helps me to answer these questions. Let's switch from Montaigne, the focus of my last entry on this topic, to Wilde. The lead quote of Bayard's Chapter 12 was the first passage of the book to seize my attention as I thumbed through it:

Speaking About Yourself

(in which we conclude, along with Oscar Wilde,
that the appropriate time span for reading a book
is ten minutes, after which you risk forgetting
that the encounter is primarily a pretext
for writing your autobiography)

My experience writing this blog biases me toward shouting out, "Amen, Brother Bayard!" But, if it is true that all of my writing is a pretext for writing my autobiography, then it is all the more remarkable that I have any readers at all. Certainly you all have figured this out by now.

Bayard claims -- and Wilde agrees -- that it cannot be any other way. You may find more interesting people writing about themselves and read what they write, but you'll still be reading about the writer. (This is cold consolation for someone like me, who knows myself to be not particularly interesting!)

Bayard explores Wilde's writing on this very subject, in particular his The Critic as Artist (HB++). Bayard begins his discussion with the surface connection of Wilde offering strident support for the idea of not reading. Wilde says that, in addition to making lists of books to read and lists of books worth re-reading, we should also make lists of books not to read. Indeed, a teacher or critic would do an essential service for the world by dissuading people from wasting their time reading the wrong books. Not reading of this sort is a "power acquired by specialists, a particular ability to grasp what is essential".

Bayard then moves on to a deeper connection. Wilde asserts in his typical fashion that the distinction between creating a work of art and critiquing a work of art is artificial. First, the artist, when creating, necessarily exercises her critical faculty in the "spirit of choice" and the "subtle tact of omission"; without this faculty no one can create art, at least not art worth considering. This is an idea that most people are willing to accept, especially those creative people who have some awareness of how they create.

But what of the critic? Many people consider critics to be parasites who at best report what we can experience ourselves and and at worst detract from our experience with their self-indulgent contributions.

Not Wilde:

Criticism is itself an art. And just as artistic creation implies the working of the critical faculty, and, indeed, without it cannot be said to exist at all, so Criticism is really creative in the highest sense of the word. Criticism is, in fact, both creative and independent.

This means that a blogger who primarily comments on the work of others can herself be making art, creating new value. By choosing carefully ideas to discuss, subtly omitting what does not matter, the critic creates a new work potentially worthy of consideration in its own right. (Suddenly, the idea of a mashup comes to mind.)

The idea of critic as an independent creator is key. Wilde says:

The critic occupies the same relation to the work of art he criticises as the artist does to the visible world of form and colour, or the unseen world of passion and thought. He does not even require for the perfection of his art the finest materials. Anything will serve his purpose.


To an artist so creative as the critic, what does subject-matter signify? No more and no less than it does to the novelist and the painter. Like them, he can find his motives everywhere. Treatment is the test. There is nothing that has not in it suggestion or challenge.

Bayard summarizes other comments from Wilde in this way:

The work being critiqued can be totally lacking in interest, then, without impairing the critical exercise, since the work is there only as a pretext.

But how can this be?? Because ultimately, the writer writes about himself. Freed from the idea that writing about something else is about that something, the writer is able to use the something as a trigger, a cue to write about the ideas that lie in his own mind. (Please read the first paragraph of the linked entry, if nothing else. Talk about not reading!)

As Wilde says,

That is what the highest criticism really is, the record of one's own soul.

Again, Bayard summarizes neatly:

Reflection on the self .. .is the primary justification for critical activity, and this alone can elevate criticism to the level of art.

As I read this chapter, I felt as if Bayard and Wilde were speaking directly to me and my own doubts as a blogger who likes to write about works I read, performances I see, and experiences as I have. It is a blogger's manifesto! Knowing and Doing feels personal to me because it is. Those works, performances, and experiences stimulate me to write, and that's okay. It is the nature of creativity to be sparked by something Other and to use that spark to express something that lies within the Self. Reading about Montaigne and his fear of forgetting what he had written was a trigger for me to write something I'd long been thinking. So I did.

I can take some consolation: This blog may not be worth reading, but not because I choose to connect what I read, see, hear, and feel to myself. It can be unworthy only to the extent that what is inside me is uninteresting.

By the way, I have just talked quite a bit about "The Critic as Artist", though I have never read it. I have only read the passages quoted by Bayard, and Bayard's commentary on it. I intend to read the original -- and begin forgetting it -- soon.


These three entries on Bayard's delightful little text cover a lot of ground in the neighborhood of guilt. We often feel shame at not having read something, or at not having grown from it. When we write for others, it is easy to become too concerned with getting things right, with being perfect, with putting on appearances. But consider this final quote from Bayard:

Truth destined for others is less important than truthfulness to ourselves, something attainable only by those who free themselves from the obligation to seem cultivated, which tyrannizes us from within and prevents us from being ourselves.

Long ago, near the beginning of this blog, I quoted Epictetus's The Enchiridion, via the movie Serendipity, of all places. That quote has a lot in common with what Bayard says here. Freeing ourselves from the obligation to seem cultivated -- being content to be thought foolish and stupid -- allows us to grow and to create. Epictetus evens refers to keeping our "faculty of choice in a state conformable to nature", just as Wilde stresses the role of critical faculty creating a work of art when we write.

Helping readers to see this truth and to release them from the obligation to appear knowing is the ultimate source of the value of How to Talk About Books You Haven't Read. Perhaps Bayard's will be proud that I mark it FB++.

Posted by Eugene Wallingford | Permalink | Categories: General, Personal

May 23, 2008 9:41 AM

My New Baby

Why is it that I feel compelled to write about getting a new Macbook Pro? Lots of people have one by now. But for a computer guy like me, a new laptop is one part professional tool and one part toy, a new user experience that shapes how I live.

my new Macbook Pro

Unlike my last laptop purchase, I splurged and bought an entry-level Macbook Pro. The 15" screen seems so much bigger than my iBook's 13" screen, because it is. The actual screen size is 13-1/8"x8-1/4" versus 9-3/4"x7-1/4", which is 50% larger. One motivation for buying the iBook last time was having a smaller machine for while flying. That worked out as planned, but even when I travel a lot I don't travel all that much. I'll have a chance to see how well the new machine travels next week when I visit Google.

Migrating files and configuration was much simpler this time. The Pro comes with a 200GB drive, rather than the 30GB(!) drive the 2005 iBook shipped with. Of course, this experience only accentuates that I am old. I think of that 30GB drive as horribly restrictive, yet not that many years ago I would have felt like a king with one. The new machine's drive is close enough to my office machine's 240-gig drive that I was able to mirror all of my files. That said, I was surprised a bit to find that the "200GB Serial ATA" drive advertised has an actual capacity of 186.31GB...)

It's a good idea for me to get a new machine every once in a while, and not just for the new technology, which is itself a wonderful advantage. I'm a creature of habit, more so than most people I know, and my brain benefits from being pulled out of its rut. My fingers must learn a new keyboard. I have to dig out a new bag to carry it in, because my OOPSLA 2005 isn't wide enough. The Leopard interface is just different enough to open my eyes to tasks that are now carried out subconsciously on the older machines.

Whenever I get a new machine and face the task of despoiling the pristine, out-of-the-box set-up of my system with my own files, I feel the urge eliminate clutter. A big part of this is always clearing out my stuff/ folder -- currently at 13,604 files and 1.46 GB on disk. (My stuff/ folder is full of folders, so I just took a break to write a quick Ruby script to count the files for me.) But this time I also paid close attention to /Applications/personal, where I store nearly all of the Mac applications I install on my machine. The only exceptions are major-league apps such as iWork and Adobe Creative Suite.

/Applications/personal on my desktop machine contains 59 apps total, including four "classic" (pre-OS ) programs. I also have two folders of apps on trial in the stuff/ folder, totaling another 27.

Hello. My name is Eugene. I am an application junkie.

Whenever I read about a cool app in a blog or an e-mail or a magazine, I go "Ooh!" and download it. I delete many of these; for the 86 on my machine, I've probably tried and deleted several multiples more. But often they find there way into a folder somewhere because I just know that I'll use them soon. But usually I don't. I don't use Paparazzi or Keyboard Cleaner, or PsyncX or WordService. They are all fine programs, I am sure, but they just never broke into my workflow. Same for Growl and AquamacsEmacs.

So this time, I decided to transfer only programs that I recall using as a part of my work or play. Right now, the new Macbook has 20 apps, ranging from workhorses such as NetNewsWire and VoodooPad to programming tools such as PLT Scheme and Scratch down to fun little utilities such as LittleSecrets and PagePacker -- and one game so far, SudokuCompanion. Let's see what I miss from the big stash, if anything...

And don't get me started on the widgets I installed back when Dashboard seemed so very cool. I almost never use a one of them. None have made it across the divide yet.

My Macbook Pro now knows me as wallingf. Perhaps I should give her a name, too. It's personal.

Posted by Eugene Wallingford | Permalink | Categories: Personal

May 16, 2008 2:55 PM

The Seductiveness of Job Security

A former student recently mentioned a tough choice he faces. He has a great job at a Big Company here in the Midwest. The company loves him and wants him to stay for the long term. He likes the job, the company, and the community in which he lives. But this isn't the sort of job he originally had hoped for upon graduation.

Now a position of just the sort he was originally looking for is available to him in a sunny paradise. He says, "I have quite a decision to make.... it's hard to convince myself to leave the secure confines of [Big Company]. Now I see why their turnover rate is so low."

I had a hard time offering any advice. When I was growing up, my dad work for Ford Motor Company in an assembly plant, and he faced insecurity about the continuance of his job several times. I don't know how much this experience affected my outlook on jobs, but in any case my personality is one that tends to value security over big risk/big gain opportunities.

Now I hold a job with greater job security than anyone who works for a big corporation. An older colleague is fond of saying Real men don't accept tenure. I first heard him say that when I was in grad school, and I remember not getting it at all. What's not to like about tenure?

After a decade with tenure, I understand better now what he means. I always thought that the security provided by having tenure would promote taking risks, even if only of the intellectual sort. But too much security is just as likely to stunt growth and inhibit taking risks. I sometimes have to make a conscious effort to push myself out of my comfort zone. Intellectually, I feel free to try new things, but pushing myself out of a comfortable nest here into a new wnvironment -- well, that's another matter. What are the opportunity costs in that?

I love what Paul Graham says about young CS students and grads having the ability to take entrepreneurial risk, and how taking those risks may well be the safer choice in the long run. It's kind of like investing in stocks instead of bonds, I think. I encourage all of my students to give entrepreneurship a thought, and I encourage even more the ones whom I think have a significant chance to do something big. There is probably a bit of wistfulness in my encouragement, not having done that myself, but I don't think I'm simply projecting my own feelings. I really do believe that taking some employment risk, especially while young, is good for many CS grads.

But when faced with a concrete case -- a particular student having to make a particular decision -- I don't feel quite so cocksure in saying "go for it with abandon". This is not abstract theory; his job and home and fiancee are all in play. He will have to make this decision on his own, and I'd hate to push him toward something that isn't right for him from my cushy, secure seat in the tower. I feel a need to stay abstract in my advice and leave him to sort things out. Fortunately, he is a bright, level-headed guy, and I'm sure he'll do fine whichever way he chooses. I wish him luck.

Posted by Eugene Wallingford | Permalink | Categories: General, Personal

April 16, 2008 4:07 PM

Right On Time

Last night, I attended a Billy Joel concert. I last saw him perform live a decade or so ago. Billy was a decade older, and I was a decade older. He looked it, and I'm sure I do, too.

But when he started to play the piano, it could have been 1998 in the arena. Or 1988. Or 1978. The music flowing from his hands and his dancing feet filled me. Throughout the night I was 19 again, then 14, 10, and 25. I was lying on my parents' living room floor; sitting in the hand-me-down recliner that filled my college dorm room; dancing in Market Square Arena with an old girlfriend. I was rebellious teen, wistful adult, and mesmerized child.

There are moments when time seems more illusion than reality. Last night I felt like Billy Pilgrim, living two-plus hours unstuck in time.

Oh, and the music. There are not many artists who can, in the course of an evening, give you so many different kinds of music. From the pounding rock of "You May Be Right" to the gentle, plaintive "She's Always A Woman", and everything between. The Latin rhythms of "Don't Ask Me Why" extended with an intro of Beethoven's "Ode to Joy", and a "Root Beer Rag" worthy of Joplin.

Last night, my daughters aged 15 and 11 attended the concert with me. Music lives on, and time folds back on itself yet again.

Posted by Eugene Wallingford | Permalink | Categories: General, Personal

March 13, 2008 8:06 PM

SIGCSE Day 1 -- This and That

[A transcript of the SIGCSE 2008 conference: Table of Contents]

This sort of entry usually comes after I write up the various conference sessions and have leftovers that didn't quite fit in an article. That may still happen, but I already have some sense of what will go where and have these items as miscellaneous observations.

First of all, I tried an experiment today. I did not blog in real-time. I used -- gasp! -- the antiquated technology of pen and paper to take notes during the sessions. On one or two occasions, I whipped open the laptop to do a quick Google search for a PhD dissertation or a book, but I steadfastly held back from the urge to type. I took notes on paper, but I couldn't fall into "writing" -- crafting sentences, then forming paragraphs, editing, ... All I could do was jot, and because I write slowly I had to be pickier about what I recorded. One result is that I paid more attention to the speakers, and less to a train of thought in my head. Another is that I'll have to write up the blog posts off-line, and that will take time!

As I looked through the conference program last night, I found myself putting on my department head hat, looking for sessions that would serve my department in the roles I now find myself in more often: CS1 for scientists, educational policy in CS, and the like. But when I got to the site and found myself having to choose between Door A and Door B... I found myself drifting into the room where Stuart Reges was talking about a cool question that seems to pick out good CS students, and the nifty assignments. Whatever my job title may be, I am a programmer and CS teacher. (More on both of those sessions in coming entries...)

Now, for a couple of non-CS, non-teaching observations.

  • I am amazed at how many healthy adults will walk out of their way, past a perfectly good set of stairs, to ride up an escalator. Sigh.
  • Staying at the discount motel over three miles away and without a car, I am relying on public buses. I have quickly learned that bus schedules are suggestions, not contracts. Deal with it. And in Portland, that often means: deal with it in the rain.
  • Schoolchildren here take standard mass transit buses to school. I never knew such a place existed.

There is so much for me to learn.

Posted by Eugene Wallingford | Permalink | Categories: General, Personal

March 06, 2008 8:07 PM

An Odd Dinner Conversation

Last night, at dinner with my family, I casually mentioned this YouTube video in which Barack Obama answers a question from a Google interviewer about how to sort a million 32-bit integers. Obama gets a good laugh when he says that "the bubble sort would be the wrong way to go". My family knows that I enjoy pointing out pop references to CS, so I figured they'd take this one in stride and move.

But they didn't. Instead, they asked questions. What is "bubble sort"? Why do they call it that? As I described the idea, they followed with more questions and ideas of their own. I told them that bubble sort was the first sorting algorithm I ever learned, programming in BASIC as a junior in high school. My wife mentioned something like the selection sort, so I told them a bit about selection sort and insertion sort, and how they are considered "better" than bubble sort.

Why? they asked. That led us to Big-Oh notation and O(n²) versus (nlogn), and why the latter is better. We talked about how we can characterize an algorithm by its running time as proportional to n² or nlogn for some factor k, and the role that k plays in complicating our comparisons. I mentioned that O(n²) and a big k are part of the reason that bubble sort is considered bad, and that's what made the answer in the video correct -- and also why I am pretty sure that Obama did not understand any of the reasoning behind his answer, which is what made his deadpan confidence worth a chuckle.

(If you would like to learn more about bubble sort and have a chuckle of your own, read Owen Astrachan's Bubble Sort: An Archaeological Algorithmic Analysis (PDF), available from his web site.)

As the conversation wound down, we talked about how we ourselves sort things, and I got to mention my favorite sorting algorithm for day-to-day tasks, mergesort.

I suspect that my younger daughter enjoyed this conversation mostly for hearing daddy the computer scientist answer questions, but my wife and freshman daughter seemed to have grokked some of what we talked about. Honest -- this wasn't just me prattling on unprovoked. It was fun, yet strange. Maybe conversations like this one can help my daughters have a sense of the many kinds of things that computer scientists think about. Even if it was just bubble sort.

Posted by Eugene Wallingford | Permalink | Categories: Computing, Personal

February 14, 2008 6:43 AM

Under Review

Leave it to George Costanza. In the episode of Seinfeld titled The Masseuse, George finally has a great relationship with a wonderful woman. Inexplicably, she likes everything about him. Yet all he can think about is Jerry's current girlfriend, a masseuse who can't stand George. Rather than turn his attention to his own loving partner, he makes such a strident effort to get the masseuse to like him that he drives her even further away -- and loses his own girl, who can't understand George's obsession. But it's really quite simple: George wants everyone to like him.

I understand that not everyone will like me. But deep inside it's easy to lose sight of that fact in the course of daily interactions. When I became department head, one of my goals was to treat everyone fairly, to be open and honest so that each member of the faculty could trust that I was giving him or her a fair hearing and doing the best I could to help him or her succeed within whatever conditions we found ourselves to be operating.

That's where George's problem tries to sneak in the door. What if I do treat everyone fairly and am open and honest; what if I do all I can so that each faculty can trust me and my intentions -- and still someone is unhappy with me? What then?

Trying to do what George tried to do is a recipe for disaster. As hard as it is sometimes, all I can do is what I can do. I should -- must -- act in a trustworthy manner, but I cannot make people like what I do, or like me. That is part of the territory. For me, though, the occasional encounter with this truth sucks a lot of psychic energy out of me.

This is the second semester of my third year as head, which means that I am undergoing a performance evaluation. I suppose the good news is that the dean feels comfortable enough with how I've done to do the review at all, rather than look for a new person for the next three-year appointment. He is using an assessment instrument developed by the IDEA Center at Kansas State. The faculty were asked to judge my performance on a number of tasks that are part of a head's job, such as "Guides the development of sound procedures for assessing faculty performance" and "Stimulates or rejuvenates faculty vitality/enthusiasm". My only role in the process was to rank each of the tasks in terms of their importance to the job.

I look at the review as both summative and formative. The summative side of the review is to determine how well I've done so far and whether I should get to keep doing it. The formative side is to give me feedback I can use to improve for the future. As you might guess from my fondness for so-called agile software development practices, I am much more interested in the formative role of the assessment. I know that my performance has not been ideal -- indeed, it's not even been close! -- but I also know that I can get better. Feedback from my colleagues and dean will help.

Though I was not asked to assess my performance on these issues, I do have a sense of my job performance. I have been only marginal in managing day-to-day affairs. That task requires a certain kind of focus and energy that I've had to develop on the job. I've also had to learn how to respond effectively in the face of a steady barrage of data, information, and requests. I have also been only marginal in "leadership" tasks, the ones that require I take initiative to create new opportunities for faculty and students to excel. This is an area where I have had a lot of ideas and discussed possibilities with the faculty, but finding time to move many of these ideas forward has been difficult.

In an area of particular importance to our department given its history, I have done a reasonable job of communicating information to the faculty, treating individual faculty fairly, and encouraging conversation. I recognized these tasks as primary challenges when I accepted my appointment and, while I had hoped to do better, I've done well so far to keep this dynamic front and center.

The results of the faculty survey are in; they arrived in my mailbox yesterday. I decided not to read the results right away... I have been a little under the weather and wanted to preserve my mental energy for work. The last session of my 5-week bash scripting course meets today, and I would rather be focused on wrapping up the class than on the data from my evaluation. I can tell myself not to fall victim to George's masseuse problem, but sometimes that is more easily done with conscious choices about how and when to engage relationships.

This afternoon, I'll look at the data, see what they can help me learn, and think about the future.

Posted by Eugene Wallingford | Permalink | Categories: Managing and Leading, Personal

February 01, 2008 8:57 AM

An Unexpected Connection

I wasn't expecting to hear John Maeda's name during the What is a Tree? talk, because I didn't know that researchers in Maeda's lab had created the language Processing. But hearing his name brought to mind something that has been in the back of my mind for a couple of months, since the close of my first theater experience. I had blogged about a few observations my mind had made about the processes of acting in and directing a play. The former were mostly introspective, and the latter were mostly external, as I watched our director coalesce what seemed like a mess into a half-way decent show. Some of these connections involved similarities I noticed between producing a play and creating software.

I made notes of a few more ideas that I hadn't mentioned yet, including:

  • "Release time" is chaos. Even with all of the practice and rehearsal, the hours before the show on opening night were a hectic time, worrisome for a few and distracting for others.
  • You hope for perfection, but there will mistakes. Just do it.
  • No matter what happens on stage or off, when you are on stage, you must stay in character. You are not yourself playing a character; you are the character.
  • As a novice player, I struggled throughout, even to the last call of the final show, with self-consciousness on stage. I think that unself-consciousness -- detachment -- is a skill that can be developed with practice. I need more.

I'm still wondering if those last two have any useful analogue in software development...

Since the show ended, I have occasionally tried to discern the value in the analogy between producing a play and creating software -- indeed, if there is any. That's where the connection to Maeda comes in. Last summer, I read the slender Laws of Simplicity, a collection of essays from Maeda's blog of the same name. The book suggest ten ways that we can design simpler systems and products. I must not have been in the right place to read the book just then, because I didn't get as much out of it as I had hoped. But one part of the book stuck with me.

For a metaphor to engage us deeply, Maeda wrote, it is essential that it relate, translate, and surprise. As I recall now, this means that the metaphor must relate the elements of the two things, that it must translate foreign elements from one of the things to the other, and that the result of this translation should surprise -- it should make us see or understand the other thing in a new way, give us insight.

There is a danger in finding analogies everywhere we look by making superficial connections. I am perhaps more prone to this risk than many other folks. That may be why I liked Maeda's relate/translate/surprise triad so much. Since reading it, I have used it as an external checkpoint for any new analogy that I want to make. If I can explain how the metaphor relates the two things, translates disparate elements, and surprises me, then I have some reason to think that the metaphor offers value -- at least more reason than just saying, "Hey, look at this cool new thing I noticed!"

To this point, I have not found the "surprise" in the theater experience that teaches me something new about how to think about making software. This doesn't mean that there is no value in the analogy, only that I haven't found it yet. By remaining skeptical a little while longer, I decrease the probability that I try to draw an inappropriate conclusion from the relationship.

Of course, just because I haven't yet found the surprise in the analogy doesn't mean that I did not find value in the experience that led me to it. A rich web of experiences is valuable in its own right, and enjoyable. It also provides the source material for learning.

Posted by Eugene Wallingford | Permalink | Categories: Personal, Software Development, Teaching and Learning

January 17, 2008 5:24 PM

A Tale of Three Days

Yesterday was the the sort of day that makes my CS friends and colleagues ask if I am crazy for being department head. It was the third day of classes this semester. A dozen students came by, for advising on course selection, for help switching sections, and the like. I produced a schedule mapping graduate assistants to open lab hours, ran it past the GAs and the faculty, and then distributed it. The phone rang repeatedly, with calls from other offices on campus and from off-campus folks asking questions about scholarship application deadlines.

Every time I started a new train of thought, an interrupt occurred. Context switch, new process, and return. Each task was, individually, just fine. In fact, I enjoy talking to students, new and returning, and helping them make choices about their studies. But little or no computer science happened.

Today was my teaching day, so I got to spend plenty of time thinking about shell scripts. That's not Computer Science, but it's computer science, and as a hacker I loved it. Of course, yesterday's interrupt-fest cut into my prep time enough that I didn't feel as prepared for class as I like to be. But I got to think about software tools, writing code, duplication, abstraction -- many of the things that make me a happy computer scientist.

Tomorrow I travel to Des Moines to help select the winners of the 2008 Prometheus Awards, the Academy Awards of IT in my state. Four hours on the road. A great outreach activity, an important role for my university, and conversation with some sharp, interesting people who are involved in my discipline's industry -- but little or no computer science.

The weekend will be here soon.

Posted by Eugene Wallingford | Permalink | Categories: Managing and Leading, Personal

January 08, 2008 5:05 PM

Admin Pushing Teaching to the Side

I have always liked the week before classes start for a new semester. There is a freshness to a new classroom of students, a new group of minds, a new set of lectures and assignments. Of course, most of these aren't really new. Many of my students this semester will have had me for class before, and most semesters I teach a course I've taught before, reusing at least some of the materials and ideas from previous offerings. Yet the combination is fresh, and there is a sense of possibility. I liked this feeling as a student, and I like it as a prof. It is one of the main reasons that I have always preferred a quarter system to a semester system: more new beginnings.

Since becoming department head, the joy is muted somewhat. For one thing, I teach one course instead of three, and instead of taking five. Another is that this first week is full of administrivia. There are graduate assistantship assignments to prepare, lab schedules to produce, last-chance registration sessions to run. Paperwork to be completed. These aren't the sort of tasks that can be easily automated or delegated or shoved aside. So they capture mindshare -- and time.

This week I have had two other admin-related items on my to-do list. First is an all-day faculty retreat my department is having later this week. The faculty actually chose to get together for what is in effect an extended meeting, to discuss the sort of issues that can't be discussed very easily during periodic meetings during the semester, which are both too short for deep discussion and too much dominated by short-term demands and deadlines. As strange as it sounds, I am looking forward to the opportunity to talk with my colleagues about the future of our department and about some concrete next actions we can take to move in the desired direction. There is always a chance that retreats like this can fall flat, and I bear some responsibility in trying to avoid that outcome, but as a group I think we can chart a strong course. One good side effect is that we will go off campus for a day and get away from the same old buildings and rooms that will fill our senses for much of the next sixteen weeks.

Second is the dean's announcement of my third-year review. Department heads here are reviewed periodically, typically every five years. I came into this position after a couple of less-than-ideal experiences for most of the faculty, so I am on a 3-year term. This will be similar to the traditional end-of-the-term student evaluations, only done by faculty of an administrator. In some ways, faculty can be much sharper critics than students. They have a lot of experience and a lot of expectations about how a department should be run. They are less likely to "be polite" out of habits learned as a child. I've been a faculty member and do recall how picky I was at times. And this evaluation will drag out for longer than a few minutes at the end of one class period, so I have many opportunities to take a big risk inadvertently. I'm not likely to pander, though; that's not my style.

I'm not all that worried. The summative part of the evaluation -- the part that judges how well I have done the job I'm assigned to do -- is an essential part of the dean determining whether he would like for me to continue. While it's rarely fun to receive criticism, it's part of life. I care what the faculty think about my performance so far, flawed as we all know it's been. Their feedback will play a large role in my determining whether I would like for me to continue in this capacity. The formative part of the evaluation -- the part that gives me feedback on how I can do my job better -- is actually something I look forward to. Participating in writers' workshops at PLoP long ago helped me to appreciate the value of suggestions for improvement. Sometimes they merely confirm what we already suspect, and that is valuable. Other times they communicate a possible incremental improvement, and that is valuable. At other times still they open doors that we did not even know were available, and that is really valuable.

I just hope that this isn't the sort of finding that comes out of the evaluation. Though I suppose that that would be valuable in its own way!

Posted by Eugene Wallingford | Permalink | Categories: Managing and Leading, Personal, Teaching and Learning

December 20, 2007 1:45 PM

An Unexpected Christmas Gift

Some students do listen to what we say in class.

Back when I taught Artificial Intelligence every year, I used to relate a story from Russell and Norvig when talking about the role knowledge plays in how an agent can learn. Here is the quote that was my inspiration, from Pages 687-688 of their 2nd edition:

Sometimes one leaps to general conclusions after only one observation. Gary Larson once drew a cartoon in which a bespectacled caveman, Zog, is roasting his lizard on the end of a pointed stick. He is watched by an amazed crowd of his less intellectual contemporaries, who have been using their bare hands to hold their victuals over the fire. This enlightening experience is enough to convince the watchers of a general principle of painless cooking.

I continued to use this story long after I had moved on from this textbook, because it is a wonderful example of explanation-based learning.

Unfortunately, Russell and Norvig did not include the cartoon, and I couldn't find it anywhere. So I just told the story and then said to the class -- every class of AI students to go through my university over a ten-year stretch -- that I hoped to find it some day.

As of yesterday, I can, thanks to a former student. Ryan heard me on that day in his AI course and never forgot. He looked for that cartoon in many of the ways I have over the years, by googling and by thumbing through Gary Larson collections in the book stores. Not too long ago, he found it via a mix of the two methods and tracked it down in print. Yesterday, on one of his annual visits (he's a local), he brought me a gift-wrapped copy. And I was happy!

Sadly, I still can't show you or any of my former students who read my blog. Sorry. I once posted another Gary Larson cartoon in a blog entry, with a link to the author's web site, only to eventually a pre-cease-and-desist e-mail asking me to pull the cartoon from the entry. I'll not play with that fire again. This is almost another illustration of the playful message of the very cartoon in question: learning not to stick one's hand into the flame from a single example. But not quite -- it's really an example of learning from negative feedback.

Thanks to Ryan nonetheless, for remembering an old prof's story from many years ago and for thinking of him during this Christmas season! Both the book and the remembering make excellent gifts.

Posted by Eugene Wallingford | Permalink | Categories: Personal, Teaching and Learning

December 10, 2007 1:19 PM

It's a Wrap

My first run as an actor has ended without a Broadway call. Nonetheless I consider it to have been successful enough. My character didn't cause any major interruptions in the flow of our three performances, and I even got us back on track a time or two. Performing in front of a crowd -- especially a crowd that contained personal friends -- was enough different from giving a lecture or speaking in public that it wracked a few nerves. But getting a laugh from a real audience was also enough different from a laugh in a lecture, too, and the buzz could feed the rest of the performance.

My first post on this topic recorded dome thoughts I had had on the relationship between developing software and directing a play. In those thoughts, the director or producer is cast as the software developer, or vice versa. In the last couple of weeks, my thoughts turned more often to my role as performer. Here are a few:

  • Before each rehearsal and performance, I found myself spending important minutes setting up my environment: making sure props were in place, adjusting positions based on any results from the last time, and finding a place backstage for my time between scenes. This felt a lot like how I set up for time writing code, getting my tools in place.
  • I wonder if there is any analogue in software development the self-consciousness I felt as I began to perform on stage? Over time, the director helped me to morph some of the self-consciousness into a sensitivity to the scene and my fellow players.

    After a while, experience helps push self-consciousness into the background. It was even possible to get into a flow where the self disappeared for a moment. I think I need more experience in character to have more experiences like that! But those moments were special.

  • Once we got into performances, I noticed a need for the same almost contradictory combination of hubris and humility that a programmer needs. At some point, I had to know my lines and scenes so well that I could nail them blind. That drove a form of confidence that let me "own" my character in a scene. Yet I had to be careful not to become too cocky, because suddenly something would go wrong and I'd find myself exposed and not at all in control. So I spent a few minutes before every scene preparing, just refreshing my memory of cues and placements and notes the director had given. That bit of humility gave me more confidence than I otherwise could have had.

Most of the relationships I noticed between acting in the play and building software were really patterns of good teams. In every scene I depended upon the presence and performance of others -- and they depended on me. Being a good teammate mattered both on stage (while performing) and off (when preparing and when taking and giving feedback). "The key to acting," said our director, "is listening to other people." Funny how that is the key to so many things.

As I look back on this (first?) experience being a player in a stage production, I think that there is a lot to this notion that developing software is like producing a play -- and that producing a play is like developing software. The two media are so different, but they are both malleable, and both ultimately depend on their audiences (users).

Over the course of two weeks or so, the director did a lot of what I call refactoring. For example, he found the equivalent of duplicated code -- lines and even larger parts of scenes that don't move the story forward, given how the rest of the play is being staged. Removing duplicated stuff frees up stage real estate and time for making other additions and changes. He also aggressively sought and deleted dead space -- moments when no one was on stage (say, in the transition between scenes) or no active was taking place (say, when lighting changed). Dead space kills the energy of the show and distracts the viewer. Dead space is a little like dead code and over-designed code -- code that isn't contributing to the application. Cut it.

Every night after rehearsal and even shows, the director "ran notes" with us. This was a time after each "iteration" dedicated to debugging and refactoring. That's good practice in software.

One other connection jumped out to me yesterday. After we closed the show, I was chatting with Scott Smith, a local filmmaker whose is real-life husband to the woman who played my wife in the show. We were discussing how filmmaking has changed in the last decade or so. In the not-so-old days folks in video were strongly encouraged to become specialists in one of the stages: writing, directing, shooting, editing, and so on. Now, with the wide availability of relatively inexpensive equipment and digital tools, and economic pressures to deliver more complete services, even veterans such as Smith find themselves developing skills across the board, becoming not a jack-of-all-trades but master of none, but rather strong in all phases of the game.

I immediately thought of extreme programming's rapid development cycle that requires programmers to be not only writers of code but also writers of stories and tests, to be able to interact with clients and to grow designs and architectures. It's hard to be a master of all trades, but the sort of move we have seen in software and in filmmaking from specialist to generalist encourages a deep competence in all areas. Too often I have heard folks say "I am a generalist" as way to explain their lack of expertise in any one area. But the new generalist is competent across the board, perhaps expert in multiple areas, and able to contribute meaningful to the whole lifecycle.

One last idea. Just before our final show, the director gave us our daily pep talk. He said that come performers view the last show as occasion to do something wacky -- to misplace someone's prop, or deliver a crazy line not from the script, or to affect some voice or mannerism on stage. That sounds like fun, he said, but remember: For the audience out in the seats today, this is the first show. They deserve to see the best version of the show that we can give. For some reason, I thought of software developers and users. Maybe my mind was just hyperactive at that moment when we were about to create our illusion. Maybe not.

Posted by Eugene Wallingford | Permalink | Categories: Personal, Software Development

December 07, 2007 4:41 PM

At the End of Week n

Classes are over. Next week, we do the semiannual ritual of finals week, which keeps many students on edge while at the same time releasing most of the tension in faculty. The tension for my compiler students will soon end, as the submission deadline is 39 minutes away as I type this sentence.

The compiler course has been a success several ways, especially in the most important: students succeeded in writing a compiler. Two teams submitted their completed programs earlier this week -- early! -- and a couple of others have completed the project since. These compilers work from beginning to end, generating assembly language code that runs on a simple simulated machine. Some of the language design decisions contributed to this level of success, so I feel good. (And I already know several ways to do better next time!)

I've actually wasted far too much time this week writing programs in our toy functional language, just because I enjoy watching them run under the power of my students' compilers.

More unthinkable: There is a greater-than-0% chance that at least one team will implement tail call optimization before our final exam period next. They don't have an exam to study for in my course -- the project is the purpose we are together -- so maybe...

In lieu of an exam, we will debrief the project -- nothing as formal as a retrospective, but an opportunity to demo programs, discuss their design, and talk a bit about the experience of writing such a large, non-trivial program. I have never found or made the time to do this sort of studio work during the semester in the compilers course, as I have in my other senior project courses. This is perhaps another way for me to improve this course next time around.

The end of week n is a good place to be. This weekend holds a few non-academic challenges for me: a snowy 5K with little hope for the planned PR and my first performances in the theater. Tonight is opening night... which feels as much like a scary final exam as anything I've done in a long time. My students may have a small smile in their hearts just now.

Posted by Eugene Wallingford | Permalink | Categories: Computing, Personal, Teaching and Learning

December 05, 2007 2:42 PM

Catch What You're Thrown

Context     You are in an Interactive Performance, perhaps a play, using Scripted Dialogue.

Problem     The performer speaking before you delivers a line incorrectly. The new line does not change the substance of the play, but it interrupts the linguistic flow.

Example     Instead of saying "until the first of the year", the performer says as "for the rest of the year".

Forces     You know your lines and want to deliver them correctly.

The author wrote the dialogue with a purpose in mind.

Delivering the line as you memorized it is the safest way for you to proceed, and also the safest route back on track.

BUT...     Delivering the scripted line will call attention to the error. This may disconcert your partner. It will also break the mood for the audience.

So:     Adapt your line to the set up. Respond in a way that is seamless to the audience, retains the key message of the story, and gets the dialogue back on track.

That is, catch what you are thrown.

Example     Change your line to say "for the rest of the year?" instead of "until the first of the year?"

Related Patterns     If the performer speaking before you misses a line entirely, or gets off the track of the Scripted Dialogue, deliver a Redirecting Line.


Postscript: This category of my blog is intended for software patterns and discussion thereof, but this is a pattern I just learned and felt a strong desire to right. I may well try to write Redirecting Line and maybe even the higher-level Scripted Dialogue and Interactive Performance patterns, if the mood strikes me and the time is available. I never thought of pattern language of performance when I signed on for this gig... And just so you know, I was the performer who mis-delivered his line in the example given above, where I first encountered Catch What You're Thrown.

Posted by Eugene Wallingford | Permalink | Categories: Patterns, Personal

November 23, 2007 9:09 AM

Now Appearing at a Theater Near You...

In a stunning departure from my ordinary behavior, I have taken an acting role in a play. My daughters were recently cast in a production of Barbara Robinson's classic children's story The Best Christmas Pageant Ever, being put on by a local church. The director is well known in our area as an actor and as the long-time director of a tremendous local children's theater, and he has just returned to the area as youth director of said church. He is also the virtual training partner to whom I have referred a few times in my entries on marathon preparation.

This play is mostly about kids and ladies, and plenty of folks auditioned for those roles. But when the one guy who auditioned for the part of the father dropped out, the production was left with a big hole. My daughters joked that I should fill in; it would be fun. My running partner-as-director assured me that I could handle what is really a small supporting role, even though I have no acting experience to speak of. After some hemming and hawing, I decided to give it a go. A compressed rehearsal schedule and a relaxed venue were enough to lower my fears, and the chance to work with my daughters -- who love to perform and who are getting pretty good at it -- was enough to convince me to take a risk.

So, in a few weeks, I will appear on stage as father Bob Bradley, immortalized in a made-for-TV film starring Loretta Swit by veteran character actor Jackson Davies.

Fortunately, my role in the play is a bit larger than the dad's role in the movie. Davies played a small, straight part, and I get to go for a laugh or two. The dad, though also gets to deliver a key passage in the story, what I call my "Linus moment", in analogy to A Charlie Brown Christmas. My lines are neither as extensive nor quite a poignant as the spotlighted soliloquy of Linus's Biblical passage, but still it is a pivotal moment. How is that for pressure on a first-time actor with no discernible natural skill? May I rise to the challenge!

I'm still not sure what to expect. I figure in the worst case we have a little fun. In the best case, perhaps learning a bit about how to deliver a line and mug for the audience will improve my "stage presence" as a teacher and as a public speaker. I usually live my life on a rather narrow path, so stretching my boundaries is almost certainly a good thing.

Posted by Eugene Wallingford | Permalink | Categories: Personal

November 21, 2007 3:28 PM

Small World

the cover of David Lodge's 'Small World'

Recently I mentioned the big pharmaceutical company Eli Lilly in an entry on the next generation of scientists, because one of its scientists spoke at the SECANT workshop I was attending. I have some roundabout personal connections to Lilly. It is based in my hometown.

When I was in high school and had moved to a small town in the next county, I used to go with some adult friends to play chess at the Eli Lilly Chess Club, which was the only old-style corporate chess club of its kind that I knew of. (Clubs like it used to exist in many big cities in the 19th and early 20th centuries. I don't know how common they are these days. The Internet has nearly killed face-to-face chess.) I recall quite a few Monday nights losing quarters for hours while playing local masters at speed chess, at 1:30-vs-5:00 odds!

Coincidentally, my high school hometown was also home to a Lilly Research Laboratories facility, which does work on vaccines, toxins, and agricultural concerns. Parents of several friends worked there, in a variety of capacities. When I was in college, I went out on a couple of dates with a girl from back home. Her father was a research scientist at Lilly in Greenfield. (A quick google search on his name even uncovers a link to one of his papers.) He is the sort of scientist that Kumar, our SECANT presenter, works with at Lilly. Interesting connection.

But I can go one step further and bring this even closer to my professional life these days. My friend's last name was Gries. It turns out that her father, Christian Gries, is brother to none other than distinguished computer scientist David Gries. I've mentioned Gries a few times in this blog and even wrote an extended review of one of his classic papers.

I don't think I was alert enough at the time to be sufficiently impressed that Karen's uncle was such a famous computer scientist. In any case, hero worship is hardly the basis for a long-term romantic relationship. Maybe she was wise enough to know that dating a future academic was a bad idea...

Posted by Eugene Wallingford | Permalink | Categories: Computing, Personal

August 30, 2007 5:57 PM

It's Not Them; It's Me

I recently realized something.

In books with academic settings, one often sees images of the professor, deep in thought, strolling along the tree-lined walks of campus. Students bustle about on the way between classes. The professor walks along, carefree, absorbed in whatever interesting problem has his or her mind. (All too often, it's a him.) Even if he is running late, has a meeting to attend or a class to lead, he hurries not. He is a professor and leads a life of his own design, even if administrators and students try to impinge on his time. Whatever deep thought occupies his mind comes first. So peaceful.

Movies show us these images, too. So peaceful.

I've never been like that. My campus setting looks much like the ones described in books and movies (though lately ours has looked more like a construction zone than an old-Ivy plat), but I always seem to be in hurry. Can't be late for class, or late for that meeting. Too much to do.

I've often asked myself, when will it be like in the books and movies.

My realization: The problem isn't with my campus or even my university. It's me.

The images in the books and movies are different because the prof ambling peacefully along isn't me. It's Professor Kingsfield. Many of these characters are clichés even when done well, but in any case they are different from me.

The only way for me to live out those images is to modify my own behavior or outlook. Peace comes from inside, not out there. But I don't think I am in need of a change... I'm not restless or dissatisfied; I'm just busy being me, solving problems and thinking about the latest something to cross my path.

So maybe what I need to change is my expectation -- the expectation that I can or even should be like the fictional people I see in those scenes. I suspect that having unrealistic expectations is the cause of as much disharmony as having the "wrong outlook". The outlook isn't always wrong. Sometimes it's just me.

Posted by Eugene Wallingford | Permalink | Categories: General, Personal

August 08, 2007 8:57 PM

Seen in the IND Airport

Sponsored outlets in the walkways of the concourses:

You and your laptop may sigh with relief now.


Sharing the outlet is good business karma.

The sponsor in this case is Chase, The Bank Formerly Known as Chase Manhattan and later as JP Morgan Chase. Each outlet plate has a blue Chase banner running down the wall from about eye level right down to the pair of outlets. The banners caught my eye, so I guess they worked. Eventually the gimmick will wear out its novelty -- perhaps it already has for other flyers, or elsewhere in the country; I don't fly often -- but I thought it was cute. Funny how changes in technology have made something as mundane as an open outlet so valuable!

Oh, and thanks to cashing in some very old, expiring frequent flyer miles, I flew first class for the first time in a long time, from Indianapolis to John Wayne/Orange County. It wasn't quite like the Seinfeld episode in which Jerry and Elaine experience the different sides of traveling first class and coach, but it was very, very nice. A good addition to my vacation.

Posted by Eugene Wallingford | Permalink | Categories: General, Personal

July 25, 2007 7:45 AM

Miscellaneous Blogging Thoughts

... at the end of a long day.

  1. I must be an old hand at blogging now. I let Knowing and Doing's third anniversary pass without comment. And I let my 500th post -- and my 512th! -- go by with no fanfare.
  2. I continue to be amazed by Google and the blogosphere. While preparing to visit my old hometown for my upcoming high school reunion, I googled "Scott Merrell ARC" in hopes of finding out if the named Mr. Merrell still owned and operated ARC Sheet Metal, where I worked as a part-time sheet metal apprentice and installer of ductwork during several high school summers. Scott had met me at local chess tournaments and took me on for a job for which I had no training or particular native talent. He patiently taught me a few skills and endured a few mistakes. I thought it might be nice to stop in to see Scott after twenty years, introduce him to my wife and daughters, and maybe give him one more shot in his pet Lasker's variation against my Petrov's Defense. It was unlikely that a small local sheet metal shop would have a web page, but it cost me nothing to try.

    I found only one relevant link -- the first link on the results page, of course -- but it was not for the shop. Instead it included a blog entry written by a friend of Scott's son, which quoted the full text of the son's eulogy for his father. My good friend and former boss died this past March after a long battle with lung disease. (In addition to being a chess hound and a professional sheet metal man, he smoked far too much.) The eulogy almost brought me to tears as it reminisced about the decent man I, too, remembered fondly and respected so. I have no simple way to contact Scott's son to thank him for sharing his eulogy, but I did leave a comment on the blog.

    Not many years ago, the idea that I could have learned about Scott's passing in this way and read the eulogy would have been unthinkable. The connection was indirect, impersonal in some ways, but deeply personal. For all its shortcomings, our technology makes the world a better place to live.

  3. I don't write a personal blog like the one that quoted Scott's eulogy, this entry and a few others notwithstanding. Dave Winer expressed one of the powerful reasons for writing a blog in his essay The unedited voice of a person. A blog like mine provides an outlet for thinking out loud, developing professional ideas in front of an audience, and sharing the small insights that would likely never appear in a refereed publication in a journal or conference. Writing without an editor creates a little fear, but soon the fear is counterbalanced by the freedom that comes from not having to carry someone else's reputation into the written word. By having readers, I do feel the weight of expectation, as I don't want to waste the valuable time of others. But the voice here can be mine, and only mine.
  4. Besides, I like Winer's explanation for why comments are not the be-all, end-all of a blog. I've always told myself and anyone who asked why I don't have comments that I would soon, but I have remained too lazy or busy to set them up. The lightweight, shell-based blogging tool I use, an old version of Nanoblogger, doesn't support comments out of the box, and in fact seems to require magical incantations to make a third-party add-on to work with it. And I don't have the time or inclination to write my own just now.

    But I don't actually mind not having comments. I sometimes miss the interactivity that comments would enable, but managing comments and combatting comment spam takes time, time that I would rather spend reading and blogging.

  5. Last summer, Brad DeLong wrote a fun but more academic essay, The Invisible College, for the Chronicle of Higher Education Review that describes well why I like to blog. Even without comments enabled, I receive e-mail from smart, interesting people all over the world who have read something I wrote here, discussing some point I made, offering alternatives, and suggesting new ideas and resources to me. My academic work benefits from this invisible college. With any luck, some of my ideas might reach the eyes of non-computer scientists and start a conversation outside the confines of my discipline.

    Oh, and he's spot on about that procrastinating thing.

Back to paradise.

Posted by Eugene Wallingford | Permalink | Categories: General, Personal

July 23, 2007 1:59 PM

Intelligent Game Playing in the News

Two current events have me thinking about AI, one good and one sad.

First, after reporting last week that checkers has been solved by Jonathan Schaeffer's team at the University of Alberta, this week I can look forward to the Man vs. Machine Poker Challenge at AAAI'07 The computer protagonist in this event, Polaris, also hails from Alberta and Schaeffer's poker group. In this event, which gets under way shortly in Vancouver, Polaris will play a duplicate match against two elite human pros, Phil Laak and Ali Eslami. Laak and Eslami will play opposite sides of the same deal against Polaris, in an attempt to eliminate the luck of the draw from the result.

I don't know much about computer card-playing. Back when I was teaching AI in the mid-1990s, I used Matthew Ginsberg's text, and from his research learned a bit about programs that play bridge. Of course, bridge players tend to view their game as a more intellectual task than poker (and as more complex than, say, chess), whereas poker introduces the human element of bluffing. It will be fun seeing how a "purely rational" being like Polaris bluffs and responds to bluffs in this match. If poker is anything at all like chess, I figure that the program's dispassionate stance will help it respond to bluffs in a powerful way. Making bluffs seems a different animal altogether.

I wish I could be in Vancouver to see the matches. Back in 1996 I was fortunate to be at AAAI'96 in Philadelphia for the first Kasparov-Deep Blue match. The human champ won a close match that year before losing to Deep Blue the next. We could tell from Kasparov's demeanor and behavior during this match, as well as from his public statements, that he was concerned that humans retain their superiority over machines. Emotion and mental intimidation were always a part of his chess.

On the contrary, former World Series of Poker champion Laak seems unconcerned at the prospect that Polaris might beat him in this match, or soon; indeed, he seems to enjoy the challenge and understand the computational disadvantage that we humans face in these endeavors. That's a healthier attitude, both long term and for playing his match this week. But I appreciated Kasparov's energy during that 1996 match, as it gave us demonstrative cues about his state of mind. I'll never forget the time he made a winning move and set back smugly to put his wristwatch back on. Whenever Garry put his watch back on, we knew that he thought he was done with the hard working of winning the game

The second story is sadder. Donald Michie, a pioneer in machine learning, has died. Unlike many of the other founders of my first love in computing, I never had any particular connection to Michie or his work, though I knew his name well from the series of volumes on machine learning that he compiled and edited, as they are staples of most university libraries. But then I read in his linked Times On-Line article:

In 1960 he built Menace, the Matchbox Educable Noughts and Crosses Engine, a game-playing machine consisting of 300 matchboxes and a collection of glass beads of different colours.

We Americans know Noughts and Crosses as tic-tac-toe. It turns out that Michie's game-playing machine -- one that needed a human CPU and peripherals in order to run -- was the inspiration for an article by Martin Gardner, which I read as a sophomore or junior in high school. This article was one of my first introductions to machine learning and fueled the initial flame of my love for AI. I even built Gardner's variant on Michie's machine, a set of matchboxes to play Hexapawn and watched it learn to play a perfect game. It was no Chinook or Deep Blue, but it made this teenager's mind marvel at the possibilities of machine intelligence.

So, I did have a more direct connection to Michie, and had simply forgotten! RIP, Dr. Michie.

Posted by Eugene Wallingford | Permalink | Categories: Computing, Personal

July 20, 2007 7:38 PM

A Reunion with Reunion

My 25th high school reunion is next month. (I can just hear the pencils at work as students, current and former, figure out just how old I am.) So I took this opportunity to re-read Alan Lightman's novel Reunion, which is about a college professor's 30th college reunion. I first read this book when it came out several years ago, but the theme was more timely this time around.

I first learned about Lightman, a physicist-turned-novelist whose fact and fiction both rest on a physics foundation, from an endnote in David Bodanis's E=mc2, which referred me to Einstein's Dreams, This was an unusual book, only a couple of dozen short chapters, that consisted of a few fictional vignettes of Einstein's thinking and discussion with Hans Bethe as he reconceptualized time for his theory of relativity, interspersed among twenty or so fictional dreams that Einstein might have had about worlds in which time behaves differently than it does in our world. For example, in one world, time passes faster when one is at higher altitudes; in another, one occasionally gets stuck to a single place in time; in yet another, time moves backward.

I found this book delightful, both creative and wonderfully written. The conversations between Einstein and Bethe sounded authentic to this non-physicist, and the dream chapters were both "whimsical" and "provocative" (words I borrow from a literary review of the book) -- what would it be like if different neighborhoods lived in different decades or even centuries? Lightman writes as a poet, spare with words and description, precise in detail. Yet the book had a serious undercurrent, as it exposed some of the questions that physicists have raised about the nature of time, and how time interacts with human experience.

Later I found Reunion. It's more of a traditional human story, and I expect that some of my friends would derogate it as "chick lit". But I disagree. First, it's a man's story: a 52-year-old man keenly aware that time has passed beyond his dreams; a 22-year-old man alive with promise unaware that he is reaching branches in time that can never be passed again. And while its structure is that of a traditional novel, the underlying current is one of time's ambiguity: looking back, looking forward, standing still. Lightman even resorts in the shortest of passages to a common device which in other authors' hands is cliché, but which in his seems almost matter of fact. It's not science fiction because it sticks close to the way a real person might feel in this world, where time seems to move monotonically forward but in which our lives are a complex mishmash of present and past, future and never-was.

I enjoyed Reunion again and, though it's a bit of downer, it hasn't diminished my anticipation of stepping back in time to see people who were once my friends, and who because of how time works in my mind will always be my friends, to reminisce about back-when and since-then, and what-now. Time's linearity will show through, of course, in the graying of hair and the onset of wrinkles...

Posted by Eugene Wallingford | Permalink | Categories: General, Personal

July 12, 2007 7:32 PM

Stay Focused

A former student recently wrote:

I am periodically reminded of a saying that is usually applied to fathers but fits teachers well -- when you are young it's amazing how little they know, but they get much smarter as I get older.

For a teacher, this sort of unsolicited comment is remarkably gratifying. It is also humbling. What I do matters. I have to stay on top of my game.

Posted by Eugene Wallingford | Permalink | Categories: Personal, Teaching and Learning

June 29, 2007 11:39 PM

Research, Prestige, and an Undergraduate Education

Philip Greenspun recently posted a provocative blog entry called Why do high school kids keep signing up to be undergrads at research universities? If you've never read any of Philip's stuff, this might seem like an odd and perhaps even naive piece. His claim is pretty straightforward: "Research universities do not bother to disguise the fact that promotion, status, salary, and tenure for faculty are all based on research accomplishments," so why don't our brightest, most ambitious high school students figure out that these institutions aren't really about teaching undergraduates? This claim might seem odd considering that Philip himself went to MIT and now teaches as an adjunct prof there. But he has an established track record of writing about how schools like Harvard, MIT, the Ivies, and their ilk could do a better job of educating undergrads, and at a lower cost.

My thoughts on this issue are mixed, though at a certain level I agree with his premise. More on how I agree below.

As an undergraduate, I went to a so-called regional university, one that grants Ph.D.s in many fields but which is not typical of the big research schools Philip considers. I chose the school for its relatively strong architecture school, which ranked in the top 15 or 20 programs nationally despite being at a school that overall catered largely to a regional student population. There I was part of a good honors college and was able to work closely with published scholars in a way that seems unlikely at a Research U. However, I eventually changed my major and studied computer science accounting. The accounting program had a good reputation, but its computer science department was average at best. It had a standard curriculum, and I was a good enough student and had enough good profs that I was able to receive a decent education and to have my mind opened to the excitement of doing computer science as an academic career. But when I arrived at grad school I was probably behind most of my peers in terms of academic preparation.

I went to a research school for my graduate study, though not one in the top tier of CS schools. It was at that time, I think, making an effort to broaden, deepen, and strengthen its CS program (something I think it has done). The department gave me great financial support and opportunities to teach several courses and do research with a couple of different groups. The undergrad students I taught and TAed sometimes commented that they felt like they were getting a better deal out of my courses than they got out of other courses at the university, but I was often surprised by how committed some of the very best researchers in the department were to their undergrad courses. Some of the more ambitious undergrads worked in labs with the grad students and got to know the research profs pretty well. At least one of those students is now a tenured prof in a strong CS program down south.

Now I teach at a so-called comprehensive university, one of those medium-sized state schools that offers neither the prestige of the big research school nor the prestige of an elite liberal arts school. We are in a no-man's land in other ways as well -- our faculty are expected to do research, but our teaching expectations and resources place an upper bound on what most faculty can do; our admissions standards grant access to a wider variety of students, but such folks tend to require a more active, more personal teaching effort.

What Greenspun says holds the essence of truth in a couple of ways. The first is that a lot of our best students think that they can only get a good education at one of the big research schools. That is almost certainly not true. The variation in quality among the programs at the less elite schools is greater, which requires students and their parents to be perhaps more careful in selecting programs. It also requires the schools themselves to do a better job communicating where their quality programs lie, because otherwise people won't know.

But a university such as mine can assemble a faculty that is current in the discipline, does research that contributes value (even basic knowledge), and cares enough about its mission to teach to devote serious energy to the classroom. I don't think that a comprehensive's teaching mission in any speaks ill of a research school faculty's desire to teach well but, as Greenspun points out, those faculty face strong institutional pressure to excel in other areas. The comprehensive school's lower admission standards means that weaker students have a chance that they couldn't get elsewhere. Its faculty's orientation means that stronger have a chance to excel in collaboration with faculty who combine interest and perhaps talent in both teaching and research.

If the MITs and Harvards don't excel in teaching undergrads, what value to they offer to bright, ambitious high school students? Commenters on the article answered in a way that sometimes struck me as cynical or mercenary, but I finally realized that perhaps they were simply being practical. Going to Research U. or Ivy C. buys you connections. For example:

Seems pretty plain that he's not looking to buy the educational experience, he's looking to buy the peers and the prestige of the university.

And in my experience of what school is good for, he's making the right decision.

You wanna learn? Set up a book budget and talk your way into or build your own facilities to play with the subject you're interested in. Lectures are a lousy way to learn anyway.

But you don't go to college to learn, you go to college to make the friends who are going to be on a similar arc as you go through your own career, and to build your reputation by association....


You will meet and make friends with rich kids with good manners who will provide critical angel funding and business connections for your startups.

Who cares if the undergrad instruction is subpar? Students admitted to these schools are strong academically and likely capable of fending for themselves when it comes to content. What these students really need is a frat brother who will soon be an investment banker in a major NYC brokerage.

It's really unfair to focus on this side of the connection connection. As many commenters also pointed out, these schools attract lots of smart people, from undergrads to grad students to research staff to faculty. And the assiduous undergrad gets to hang around with them, learning from them all. Paul Graham would say that these folks make a great pool of candidates to be partners in the start-up that will make you wealthy. And if strong undergrad can fend for him- or herself, why not do it at Harvard or MIT, in a more intellectual climate? Good points.

But Greenspun offers one potential obstacle, one that seems to grow each year: price. Is the education an undergrad receives at an Ivy League or research school, intellectual and business connections included, really worth $200,000? In one of his own comments, he writes:

Economists who've studied the question of whether or not an Ivy League education is worth it generally have concluded that students who were accepted to Ivy League schools and chose not to attend (saving money by going to a state university, for example) ended up with the same lifetime income. Being the kind of person who gets admitted to Harvard has a lot of economic value. Attending Harvard turned out not to have any economic value.

I'm guessing, though, that most of these students went to a state research university, not to a comprehensive. I'd be curious to see how the few students who did opt for the less prestigious but more teaching-oriented school fared. I'm guessing that most still managed to excel in their careers and amass comparable wealth -- at least wealth enough to live comfortably.

I'm not sure Greenspun thinks that everyone should agree with his answer so much as that they should at least be asking themselves the question, and not just assuming the prestige trumps educational experience.

This whole discussion leads me to want to borrow a phrase from Richard Gabriel that he applies to talent and performance as a writer. The perceived quality of your undergraduate institution does not determine how good you can get, only how fast you get can good.

I read Greenspun's article just as I was finishing reading the book Teaching at the People's University, by Bruce Henderson. This book describes the history and culture of the state comprehensive universities, paying special attention to the competing forces that on the one hand push their faculty to teach and serve an academically diverse student body and on the other expects research and the other trappings of the more prestigious research schools. Having taught at a comprehensive for fifteen years now, I can't say that the book has taught me much I didn't already know about the conflicting culture of these schools, but it paints a reasonably accurate picture of what the culture is like. It can be a difficult environment in which to balance the desire to pursue basic research that has a significant effect in the world and the desire to teach a broad variety of students well.

There is no doubt that many of the students who enroll in this sort of school are served well, because otherwise they would have little opportunity to receive a solid university education; the major research schools and elite liberal arts schools wouldn't admit them. That's a noble motivation and it provides a valuable service to the state, but what about the better students who choose a comprehensive? And what of the aspirations of faculty who are trained in a research-school environment to value their careers by the intellectual contribution they make to their discipline? Henderson does a nice job laying these issues out for people to consider explicitly, rather than to back into them when their expectations are unmet. This is not unlike what Greenspun does in his blog entry, laying an important question on the line that too often goes unasked until the answer is too late to matter.

All this said, I'm not sure that Greenspun was thinking of the comprehensives at all when he wrote his article. The only school he mentions as an alternative to MIT, Harvard, and the other Ivies is the Olin College of Engineering, which is a much different sort of institution than a mid-level state school. I wonder whether he would suggest that his young relative attend one of the many teacher-oriented schools in his home state of Massachusetts?

After having experienced two or three different kinds of university, would I choose a different path for myself in retrospect? This sort of guessing game is always difficult to play, because I have experienced them all under different conditions, and they have all shaped me in different ways. I sometimes think of the undergraduates who worked in our research lab while I was in grad school; they certainly had broader and deeper intellectual experiences than I had as as undergraduate. But as a first-generation university attendee I grew quite a bit as an undergraduate and had a lot of fun doing it. Had I been destined for a high-flying academic research career, I think I would have had one. Some of my undergrad friends have done well on that path. My ambition, goals, and inclinations are well suited for where I've landed; that's the best explanation for why I've landed here. Would my effect on the world have been greater had I started at a Harvard? That's hard to say, but I see lots of opportunities to contribute to the world from this perch. Would I be happier, or a better citizen, or a better father and husband? Unlikely.

I wish Greenspun's young relative luck in his academic career. And I hope that I can prepare my daughters to choose paths that allow them to grow and learn and contribute.

Posted by Eugene Wallingford | Permalink | Categories: General, Personal, Teaching and Learning

June 13, 2007 4:05 PM

BASIC and COBOL Cross My Path

I don't run into Basic and Cobol all that often these days, but lately they seem to pop up all over. Once recently I even ran into them together in an article by Tim Bray on trends in programming language publishing:

Are there any here that might go away? The only one that feels threatened at all is VB, wounded perhaps fatally in the ungraceful transition to .NET. I suppose it's unlikely that many people would pick VB for significant new applications. Perhaps it's the closest to being this millennium's COBOL; still being used a whole lot, but not creatively.

Those are harsh words, but I suppose it's true that Cobol is no longer used "creatively". But we still receive huge call for Cobol instruction from industry, both companies that typically recruit our students and companies in the larger region -- Minneapolis, Kansas City, etc. -- who have learned that we have a Cobol course on the books. Even with industry involvement, there is effectively no student demand for the course. Whether VB is traveling the same path, I don't know. Right now, there is still decent demand for VB from students and industry.

Yesterday, I ran into both languages again, in a cool way... A reader and former student pointed out that I had "hit the big leagues" when my recent post on Alan Kay started scoring points at programming.reddit.com. When I went there for a vanity stroke, I ran into something even better, a Sudoku solver written in Cobol! Programmers are a rare and wonderful breed. Thanks to Bill Price for sharing it with us. [1]

While looking for a Cobol compiler for my Intel Mac [2], I ran instead into Chipmunk Basic, "an old-fashioned Basic interpreter" for Mac OS. This brings back great memories, especially in light of my upcoming 25th high school reunion. (I learned Basic as a junior, in the fall of 1980.) Chipmunk Basic doesn't seem to handle my old graphics-enabled programs, but it runs most of the programs my students wrote back in the early 1990s. Nice.

I've been considering a Basic-like language as a possible source language for my compiler students this fall. I first began having such thoughts when I read a special section on lightweight languages in a 2005 issue of Dr. Dobbs' Journal and found Tom Pitman's article The Return of Tiny Basic. Basic has certain limitations for teaching compilers, but it would be simple enough to tackle in full within a semester. It might also be nice for historical reasons, to expose today's students to something that opened the door to so many CS students for so many years.


[1] I spent a few minutes poking around Mr. Price's website. In some sort of cosmic coincidence, it seems that Mr. Price is took his undergraduate degree at the university where I teach (he's an Iowa native), and is an avid chessplayer -- not to mention a computer programmer! That's a lot of intersection with my life.

[2] I couldn't find a binary for a Mac OS X Cobol, only sources for OpenCOBOL. Building this requires building some extension packages that don't compile without a bunch of tinkering, and I ran out of time. If anyone knows of a decent binary package somewhere, please drop me a line.

Posted by Eugene Wallingford | Permalink | Categories: Computing, Personal, Software Development

May 25, 2007 2:11 PM

Read My Blog

If you don't how will you know how clever I am?

Recently I wrote about the availability heuristic and how it may affect student behavior. Schneier tells us that this is often a useful rule of thumb, and it has served us well evolutionarily. But our changing world may be eroding its value, perhaps even making it dangerous in some situations:

But in modern society, we get a lot of sensory input from the media. That screws up availability, vividness, and salience, and means that heuristics that are based on our senses start to fail. When people were living in primitive tribes, if the idea of getting eaten by a saber-toothed tiger was more available than the idea of getting trampled by a mammoth, it was reasonable to believe that--for the people in the particular place they happened to be living--it was more likely they'd get eaten by a saber-toothed tiger than get trampled by a mammoth. But now that we get our information from television, newspapers, and the Internet, that's not necessarily the case. What we read about, what becomes vivid to us, might be something rare and spectacular. It might be something fictional: a movie or a television show. It might be a marketing message, either commercial or political. And remember, visual media are more vivid than print media. The availability heuristic is less reliable, because the vivid memories we're drawing upon aren't relevant to our real situation.

I sometimes wonder if my omnivorous blogging and promiscuous referencing of many different sources create a situation in which my readers attribute brilliance to me that rightly belongs to my sources.

A little part of my ego thinks that this would be okay. (You didn't read that here.)

However, if you finish the Schneier paragraph I quoted above, you will see that just the opposite is probably true:

And even worse, people tend not to remember where they heard something--they just remember the content. So even if, at the time they're exposed to a message they don't find the source credible, eventually their memory of the source of the information degrades and they're just left with the message itself.

So you'll remember the ideas I toss out, but you'll eventually forget that you read them here. And so you will not be able to blame me if it turns out to be nonsense...

Maybe you'd better not read my blog after all.

Posted by Eugene Wallingford | Permalink | Categories: Personal

May 17, 2007 11:08 AM

Quick Hits

Over the last couple of months, I've been collecting some good lines and links to the articles that contain them. Some of these may show up someday in something I write, but it seems a shame to have them lie fallow in a text file until then. Besides, my blog often serves as my commonplace book these days. All of these pieces are worth reading for more than the quote.

If the code cannot express itself, then a comment might be acceptable. If the code does not express itself, the code should be fixed.
-- Tim Ottinger, Comments Again

In a concurrent world, imperative is the wrong default!
-- Tim Sweeney of Epic Games, The Next Mainstream Programming Language: A Game Developer's Perspective, an invited talk at ACM POPL'06 (full slides in PDF)

When you are tempted to encode data structure in a variable name (e.g. Hungarian notation), you need to create an object that hides that structure and exposes behavior.
-- Uncle Bob Martin The Hungarian Abhorrence Principle

Lisp... if you don't like the syntax, write your own.
-- Gordon Weakliem, Hashed Thoughts, on simple syntax for complex data structures

Pairing is a practice that has (IIRC) at least five different benefits. If you can't pair, then you need to find somewhere else in the process to put those benefits.
-- John Roth, on the XP mailing list

Fumbling with the gear is the telltale sign that I'm out of practice with my craft. ... And day by day, the enjoyment of the craft is replaced by the tedium of work.
-- Mike Clark, Practice

So when you get rejected by investors, don't think "we suck," but instead ask "do we suck?" Rejection is a question, not an answer.
-- Paul Graham, The Hacker's Guide to Investors

Practice. Question rejection.

Posted by Eugene Wallingford | Permalink | Categories: Computing, Personal, Software Development

April 12, 2007 8:16 AM

Kurt Vonnegut Has Come Unstuck in Time

Be careful what you pretend to be
because you are what you pretend to be.

Kurt Vonnegut

Sometimes, the universe speaks to us and catches us unaware.

Yesterday, I attended a workshop, about which I will have more to say later today. Toward the end, I saw a quote that struck me as an expression of this blog's purpose, and almost an unknowing source for the name of this blog:

Learning is about ... connecting teaching and knowing to action.

Connecting knowing to doing. That's what this blog is all about.

But long time readers know that "Knowing and Doing" almost wasn't the name of my blog. I considered several alternatives. Back in November 2004, I wrote about some of the alternatives. Most of the serious candidates came from Kurt Vonnegut, my favorite author. Indeed, that post wasn't primarily about the name of my blog but about Vonnegut himself, who was celebrating his 82nd birthday.

Here we are, trapped in the amber of the moment.
There is no why.

And then I wake up this morning to find the world atwitter with news of Vonnegut's passing yesterday. I'm not sure that anyone noticed, but Vonnegut died on a notable unbirthday, five months from the day of his birth. I think that Vonnegut would have liked that, as a great cosmic coincidence and as a connection to Lewis Carroll, a writer whose sense of unreality often matched Vonnegut's own. More than most, Kurt was in tune with just how much of what happens in this world is coincidence and happenstance. He wrote in part to encourage us not to put too much stock in our control over a very complex universe.

Busy, busy, busy.

Many people, critics included, considered Vonnegut a pessimist, an unhappy man writing dark humor as a personal therapy. But Vonnegut was not a pessimist. He was at his core one of the world's great optimists, an idealist who believed deeply in the irrepressible goodness of man. He once wrote that "Robin Hood" and the New Testament were the most revolutionary books of all time because they showed us a world in which people loved one another and looked out for the less fortunate. He wrote to remind us that people are lonely and that we have it in our own power to solve our own loneliness and the loneliness of our neighbors -- by loving one another, and building communities in which we all have the support we need to live.

Live by the foma that make you
brave and kind and healthy and happy.

I had the good fortune to see Kurt Vonnegut speak at the Wharton Center in East Lansing when I was a graduate student at Michigan State. I had the greater good fortune to see him speak when he visited UNI in the late 1990s. Then I saw his public talk, but I also sat in on a talk he gave to a foreign language class, on writing and translation. I also was able to sit in on his intimate meeting with the school's English Club, where he sat patiently in a small crowded room and told stories, answered questions, and generally fascinated awestruck fans, whether college students or old fogies like me. I am forever in the debt of the former student who let me know about those side events and made sure that I could be there with the students.

Sometimes the pool-pah
exceeds the power of humans to comment.

On aging, Vonnegut once said, "When Hemingway killed himself he put a period at the end of his life; old age is more like a semicolon." But I often think of Vonnegut staring down death and God himself in the form of old Bokonon, the shadow protagonist of his classic Cat's Cradle:

If I were a younger man, I would write a history of human stupidity; and I would climb to the top of Mount McCabe and lie down on my back with my history for a pillow; and I would take from the ground some of the blue-white poison that makes statues of men; and I would make a statue of myself, lying on my back, grinning horribly, and thumbing my nose at You Know Who.

The blue-white poison was, of course, Ice Nine. These days, that is the name of my rotisserie baseball team. I've used Vonnegut's words as names many times. Back at Ball State, my College Bowl team was named Slaughterhouse Five. (With our alternate, we were five.)

Kurt Vonnegut was without question my favorite writer. I spent teenage years reading Slaughterhouse Five and Cat's Cradle, Welcome to the Monkey House and Slapstick, The Sirens of Titan and Breakfast of Champions and Player Piano, the wonderfully touching God Bless You, Mr. Rosewater and the haunting Mother Night. Later I came to love Jailbird and Galapagos, Deadeye Dick and Hocus Pocus and especially Bluebeard. I reveled in his autobiographical collages, too, Wampeters, Foma, and Granfalloons, Palm Sunday, Fates Worse Than Death, and Timequake. His works affected me as much or more than those of any of the classic writers feted by university professors and critics.

The world is a lesser place today. But I am happy for the words he left us.

Tiger gotta hunt.
Bird gotta fly.
Man gotta sit and wonder why, why, why.

Tiger gotta sleep.
Bird gotta land.
Man gotta tell himself he understand.

If you've never read any Vonnegut, try it sometime. Start with Slaughterhouse Five or Cat's Cradle, both novels, or Welcome to the Monkey House, a collection of his short stories. Some of his short stories are simply stellar. If you like Cat's Cradle, check out my tabulation of The Books of Bokonon, which is proof that a grown man can still be smitten with a really good book.

And, yes, I still lust after naming my blog The Euphio Question.

Rest in peace, Kurt.

Posted by Eugene Wallingford | Permalink | Categories: General, Personal

April 06, 2007 6:20 PM

Two, to Close the Week

... to the Sixth

My dad turned 64 yesterday. That's a nice round number in the computing world, though he might not appreciate me pointing that out. It's hard for me to imagine him, or me, any different than we were when I was a little boy growing up at home. It's also hard for me to imagine that someday soon my daughter might be thinking the same about the two of us. Perhaps I need a bigger imagination.

... Months

This is the time of the academic year when folks seeking jobs at other institutions, in particular administrative promotions, begin to learn of their good fortune and to plan to depart. Several of my colleagues at the university will be moving on to new challenges after this academic year.

In a meeting this week, one such colleague said something that needed to be said, but which most people wouldn't say. It was on one of those topics that seems off limits, for political or personal reasons, and so it usually just hangs in the air like Muzak.

Upon hearing the statement, another colleague joked, "Two months. You have two months to speak the truth. Two months to be a truth teller."

It occurred to me then that this must be quite a liberating feeling -- to be able to speak truths that otherwise will go unspoken. Almost immediately on the heels of this thought, it occurred to me just how sad it is that such truths go unspoken. And that I am also unwilling to speak them. Perhaps I need greater courage, or more skill.

Posted by Eugene Wallingford | Permalink | Categories: General, Managing and Leading, Personal

March 30, 2007 12:06 PM

One of Those Weeks

I honestly feel like my best work is still ahead of me.
I'm just not sure I can catch up to it.

I owe this gem, which pretty much sums up how I have felt all week, to comedian Drew Hastings, courtesy of the often bawdy but, to my tastes, always funny Bob and Tom Show. Hastings is nearly a decade older than I, but I think we all have this sense sooner or later. Let's hope it passes!

I owe you some computing content, so here is an interview with Fran Allen, who recently received the 2006 Turing Award. She challenges us to recruit women more effectively ("Could the problem be us?") and to help our programming languages and compilers catch up with advances in supercomputing ("Only the bold should apply!")

Posted by Eugene Wallingford | Permalink | Categories: Computing, Personal

March 09, 2007 10:17 AM

SIGCSE Day 1: A Conference First

the Cincinnati skyline

My roommate and I are staying in the Radisson Riverfront, which is right across the river from downtown Cincinnati at the nexus of the Ohio River and I-75. The view from our 14th-floor room is good.

So there I was, settling in after a long day at the conference. About 10 PM, the phone rings. Odd. The caller asks for me. Odd again. It's the front desk. The local police have asked all guests to come down to the lobby.

Apparently, someone had shot a bullet into a 12th-floor room. From somewhere outside.


Down we went to the lobby. We heard lots of curious smalltalk, and no small amount impatience at being inconvenienced by this interruption. Some commented that we hardly seemed safer all herded into one place, in front of wide glass lobby windows open to the interstate exit.

After 25 minutes or so, the chief of the Covington Police Department called us together. "Welcome to Covington!" he offered in good humor. He explained what had happened, what the police had done to investigate, and that they now believed us to be safe. He thanked us for our patience and wished us a good visit. I can imagine that he is a good sort of person to have as a police chief -- a big part of the job is communicating with people who are in varying states of distress.

The rest of the night passed without event.

Let's see if OOPSLA can top this.

Posted by Eugene Wallingford | Permalink | Categories: Personal

March 07, 2007 11:04 PM

Thinking Hard to Understand

Heard on my drive to SIGCSE today:

These experiences have caused him to think very hard about what he is doing and where he is going. And the result of all this thinking is that he now understands he doesn't know what he is doing or where he is going.

This quote is about Ray Porter, a character in Steve Martin's novella Shopgirl, which I listened on my drive to SIGCSE today. While I am in most ways nothing at all like the divorced, 50-something Porter, I can certainly appreciate his sudden need to think very hard and his sudden realization that he is essentially clueless. Over the course of my career, I had grown to feel comfortable in my roles as an academic, as teacher and scholar. Which I switched into the Big Office Downstairs, I just assumed that things would proceed as usual.

But after a year and a half as department head, I experience occasional moments of "midterm crisis", in which I think that I don't really know what I'm doing or where I'm going. I often have a pretty good 50,000-foot view of what I want, but down in the trenches I usually feel a little disoriented. With experience, things have gotten better, but a year filled with academic program review, two time-consuming searches, and a curriculum revision have sapped my reservoirs of creativity and energy.

At least now I think I understand that I don't know what I am doing or where I am going. You know what they say about acceptance being the first step toward recovery!

By the way, I do recommend Shopgirl. I have read the book and then listened to it several times on tape while driving to PLoPs, SIGCSEs, and ICFPs. For some reason, Martin's writing holds my attention, and the story is sweet enough that I can get over constantly wondering, "Why does she put up with this?" Martin is a surprisingly good writer; though he is never going to win a Nobel Prize, he can spin a decent short yarn. My first exposure to his literary work was Picasso at the Lapin Agile, a stage play about a fantasy meeting between Picasso and Einstein at a Paris bar around the turn of the century.

Oh, and as for Shopgirl -- I haven't seen the movie yet! I'm glad that I read the book first, and then heard it read before seeing the film version. Just knowing that Martin and the glorious Clair Danes play the leading roles has changed my experience of the book...

Posted by Eugene Wallingford | Permalink | Categories: Managing and Leading, Personal

February 20, 2007 11:58 PM

A State Conformable to Nature

In the beginning, I blogged on the danger of false pride and quoted the Stoic philosopher Epictetus. Now I have encountered another passage from Epictetus, at the mind hacker site Hacks

When you are going about any action, remind yourself what nature the action is. If you are going to bathe, picture to yourself the things which usually happen in the bath: some people splash the water, some push, some use abusive language, and others steal. Thus you will more safely go about this action if you say to yourself, "I will now go bathe, and keep my own mind in a state conformable to nature." And in the same manner with regard to every other action. For thus, if any hindrance arises in bathing, you will have it ready to say, "It was not only to bathe that I desired, but to keep my mind in a state conformable to nature; and I will not keep it if I am bothered at things that happen."

The notion of a "state conformable to nature" was central to his injunction against false pride, and here it remains the thoughtful person's goal, this time in the face of all that can go wrong in the course of living. This quote also resonates with me, because, just as I am inclined toward a false pride, I have a predisposition toward letting small yet expectable hindrances interfere with my frame of mind. Perhaps predisposition is the wrong word; perhaps it's just a bad habit.

As is often the case for me, after a second or third positive reference is all I need to commit to reading more. In the coming weeks, I now plan to read the Discourses of Epictetus. We even have a copy on our bookshelf at home. (My wife's more classical education proves useful to me again!)

Posted by Eugene Wallingford | Permalink | Categories: Personal, Teaching and Learning

February 18, 2007 4:25 PM

Respite in Hard Work, Done Somewhere Else

As I prepared to leave for ChiliPLoP 2007, I looked to the trip as almost a vacation. While I will be working steadily through the 76 hours or so in Arizona, both on elementary patterns and various and sundry school duties, I will be off the treadmill that have been the last few days. I've hardly had time to breathe since Wednesday morning:

Wednesday: Prepare for and sit in on meetings all day, including a faculty meeting. Scramble to make last-minute changes to our fall semester schedule before the secretary goes on vacation. Exercise for an hour with my older daughter in her ballet class. I was in the class, and did all of the "floor barre" work that the rest of the class did. (At least that was fun time with Sarah!) For an old guy, I did all right. Sprint home to pack a quick overnight bag. Drive two hours to Des Moines. Crash in motel bed.

Thursday: Attend 7:00 AM breakfast at the State Capitol, sponsored by the Department of Economic Development to encourage state legislators to fully fund the department's budget request for 2007-2008. Mingle with legislators, and visited with IT bigwigs from most of the major players in the state. After two hours, drive two hours back home. Prepare for class. Meet my Programming Languages class. Attend meeting. Give dinner talk to local Kiwanis club on my department's efforts to participate in state economic development through curriculum and research projects that partner with regional companies. Crash in my own bed.

Friday: Arrive at office by 6:30 AM to do some leftover work. Coach team of local eighth graders who are preparing for a math competition. After several months, the competition is here -- tomorrow. Spend four hours visiting with prospective students and their parents. Scramble all afternoon to tie up loose ends in the office. Take one daughter to orchestra practice and then to play rehearsal. Pack for ChiliPLoP.

Saturday: Take eighth graders to math competition at 8:00 AM. Fill time and watch until 1:30. Take one daughter to play rehearsal. Kiss other daughter, already at rehearsal, good-bye for a few days. Head home, kiss wife good-bye, load bags in car, and hit road for 3+ hour drive to Minneapolis. (Take short nap along the way.) Grab dinner with friend. Crash on friend's couch.

Sunday: Rise at 5 AM for ride to airport. Encounter usual delays. Board plan at 6:30 AM for 7:00 AM flight. Then ... sit for two hours before take-off as plane requires computer system maintenance. I don't usually think of a two-hour in-plane delay as a respite, but this one was. I took a nap!

We are now in the air, approaching Phoenix. ChiliPLoP, as busy as it always, made more busy by some necessary work from back home, will seem a break.

This sort of week may be no big deal to my consultant friends, or maybe even to my academic friends with big outreach portfolios. But it's new to me. While each activity of the week offered value, I found myself looking forward to the TSA and the plane. Extra time of the plane didn't bother me.

Landing will be better. Work on computer science with some of my favorite colleagues will be better.

A run in the sun will be better.

Posted by Eugene Wallingford | Permalink | Categories: Personal