AKA “When non-economists try to maximize”.

I liked this:

What is rational behavior, anyway? In economic terms, Mr. Ariely said, “rational would mean that you take all possible information into account and you make the optimal decision. But I have a more relaxed definition, which is that rational decisions are those you make and don’t regret later.” Seen in this way, the pleasure of the $4 coffee you still drink may be rational. That is, “unless I interview you three years from now,” Mr. Ariely added, “and you tell me you regret not saving that money for beer.”

http://www.nytimes.com/2008/11/20/garden/20math.html