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 ArrowFamily is a difficult matter. I must admit I do not know that the state can intervene successfully in a family. It's a fact that everything is connected with the individualist temperament, the kind of economic environment which stresses the individual, but this is not directly the result of a state policy, nor do I see any good way by which the state could intervene except in some marginal ways.
Kenneth ArrowI think the development of the venture capital system has been an example of something which is a successful improvement in risk-bearing. It doesn't exactly remove the risks at the beginning, but at least creates greater rewards at a slightly later stage and therefore encourages, say, small companies to engage in technologically risky enterprises.
Kenneth ArrowThere is a bit of a problem with the match between derivative securities markets and the primary markets. We have long ago instituted principles, essentially high margin requirements, to prevent certain instabilities in the stock market, and I think they're basically correct. The trouble is that there's a linkage, let's say, between something like the stock market and the index futures markets, and the fact that the margin requirements are very different, for example, played some role in the October '87 crash.
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