It seems to me that this failure of the economists to guide policy more successfully is closely connected with their propensity to imitate as closely as possible the procedures of the briliantly successful physical sciences--an attempt which in our field may lead to outright error.

If man is not to do more harm than good in his efforts to improve the social order, he will have to learn that in this, as in all other fields where essential complexity of an organized kind prevails, he cannot acquire the full knowledge which would make mastery of the events possible. He will therefore have to use what knowledge he can achieve, not to shape the results as the craftsman shapes his handiwork, but rather to cultivate a growth by providing the appropriate environment, in the manner in which the gardener does this for his plants.

In their effort to keep consumer prices stable, the Federal Reserve governors increased interest rates and sold government bonds, a remedy that Keynes had advocated in the Tract. But, Hayek argued, the consumer price index that inspired their actions was a blunt instrument that revealed little about the fluctuations of prices in individual commodities. It was therefore a misleading indicator by which to adjust general interest rates. He found that to pin interest rate and monetary policy on such a broad and inaccurate index would as likely exacerbate as cure the problem the Fed set out to solve. He concluded, "An index of the general price level cannot yield any relevant information as to the course of the cycle, nor more importantly can it do so at the right time."