TITLE: "Good Character" as an Instance of Postel's Law AUTHOR: Eugene Wallingford DATE: September 22, 2015 2:57 PM DESC: ----- BODY: Mike Feathers draws an analogy I'd never thought of before in The Universality of Postel's Law: what we think of as "good character" can be thought of as an application of Postel's Law to ordinary human relations.
Societies often have the notion of 'good character'. We can attempt all sorts of definitions but at its core, isn't good character just having tolerance for the foibles of others and being a person people can count on? Accepting wider variation at input and producing less variation at output? In systems terms that puts more work on the people who have that quality -- they have to have enough control to avoid 'going off' on people when others 'go off on them', but they get the benefit of being someone people want to connect with. I argue that those same dynamics occur in physical systems and software systems that have the Postel property.These days, most people talk about Postel's Law as a social law, and criticisms of it even in software design refer to it as creating moral hazards for designers. But Postel coined this "principle of robustness" as a way to talk about implementing TCP, and most references I see to it now relate to HTML and web browsers. I think it's pretty cool when a software design principle applies more broadly in the design world, or can even be useful for understanding human behavior far removed from computing. That's the sign of a valuable pattern -- or anti-pattern. -----