"The economist studies the disposal of scarce means. He is interested in the way different degrees of scarcity of different goods give rise to different ratios of valuation between them, and he is interested in the way in which changes in conditions of scarcity, whether coming from changes in ends or changes in means—from the demand side or the supply side—affect these ratios. Economics is a science which studies human behavior as a relationship between ends and scarce means which have alternative uses."

“I shall always regard this aspect of my dispute with Keynes as the greatest mistake of my professional career, and the book, The Great Depression, which I subsequently wrote, partly in justification of this attitude, as something which I would willingly see be forgotten. Now I still think that there is much in this theory as an explanation of a possible generation of boom and crisis. But, as an explanation of what was going on in the early ’30s, I now think it was misleading. Whatever the genetic factors of the pre-1929 boom, their sequelae, in the sense of inappropriate investments fostered by wrong expectations, were completely swamped by vast deflationary forces sweeping away all those elements of constancy in the situation which otherwise might have provided a framework for an explanation in my terms. The theory was inadequate to the facts. Nor was this approach any more adequate as a guide to policy. Confronted with the freezing deflation of those days, the idea that the prime essential was the writing down of mistaken investments and the easing of capital markets by fostering the disposition to save and reducing the pressure on consumption was completely inappropriate. To treat what developed subsequently in the way which I then thought valid was as unsuitable as denying blankets and stimulants to a drunk who has fallen into an icy pond, on the ground that his original trouble was overheating.”