When you look at any experimental work not directly related to economics, but trying to test rational behavior in other ways, experiments have conspicuously failed to show rational behavior. Macro evidence certainly suggests deviations from rationality, but I don't want to say the rationality hypothesis is completely wrong. If you have any introspective idea or experimental idea about people's behavior, it seems to be incompatible with the really full scale rational expectations.
Kenneth ArrowThe intrinsic social structure, the family structure and so forth, is certainly in a very bad state. And I think that this is showing up in productivity. I think part of the reason, and I can't prove this, we're seeing a decline in some places is the breakup of the family, which is partly the result of an extreme form of individualism.
Kenneth ArrowThere's only one problem that bothers me. And that's something my theorem [ of Impossibility] really doesn't cover. In my theorem I was assuming people vote sincerely. The trouble with methods where you have three or four classes, I think if people vote sincerely they may well be very satisfactory. The problem is the incentive to misrepresent your vote may be high.
Kenneth ArrowOne doesn't like instabilities in markets; they may be damaging, but probably not fatal, as the October '87 crash showed. It turned out to be essentially inconsequential. So if that's true, I'm not very worried about the welfare of those who are investing any more than I am about the welfare of those who go into casinos.
Kenneth Arrow