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 brilliantly successful physical sciences--an attempt which in our field may lead to outright error. It is an approach which has come to be described as the "scientistic" attitude--an attitude which, as I defined it some thirty years ago, "is decidedly unscientific in the true sence of the word, since it invloves a mechanical and uncritical application of habits of thought to fields different from those in which they have been formed."