my thinking on rational/irrational behaviour is aided by remembering that we are all animals, and that what we think of as rational thought is simply an adaptation that allowed more of us to survive relative to our less sophisticated genetic cousins. If irrational people were to fuck more often than rational people, and produce more healthy offspring that reach adulthood, then in evolution's eyes being irrational is better than being rational. It's more complex than that, but you see what I mean. It so happens that rational people developed and refined an economic system that rewards being rational, being intelligent -- most of our other assumptions about human economic behaviour proceed from there

--mza.