It's a cultural norm. If someone constantly defects in prisoner dilemma he's violating the norm of fairness and deverses to be punished for doing so.
Except that in a lot of accusations of "unfairness" there is no obvious prisoner-dilemma-defection going on.
If it's worth saying, but not worth its own post (even in Discussion), then it goes here.
Thread started before the end of the last thread to ecourage Monday as first day.