The world is changing. We're not really proceeding on a stationary basis.

It seems to me that at least as far as the financial markets are concerned, there is increasing evidence against rational expectations, even at the macro level.

I think the idea that a society has to be responsible for all of its citizens, those who do well and those who do not, is really a precondition of a good society.

One 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.

Vast ills have followed a belief in certainty.

Classic economic theories recognize public goods aspects of one kind or another - the need for economic intervention in, obviously, the supply of infrastructure and of education. We're not supplying that infrastructure at an appropriate rate today. I don't doubt it isn't just money; it's organization and goals and so forth.

Unsolved problems, that's one of the great signs of progress in my opinion.