Without getting into the question of Derb’s own views, on which I am of course no expert, let me just suggest that anyone interested in the question of scientism could hardly do better than to read F.A. Hayek’s wonderful book The Counter-Revolution of Science, which is about (among other things) the misuse of scientific ways of thinking in areas of inquiry in which they do not properly belong. In explaining his own extensive use of the term “scientism” in the book, Hayek writes:
It need scarcely be emphasized that nothing we shall have to say is aimed against the methods of Science in their proper sphere or is intended to throw the slightest doubt on their value. But to preclude any misunderstanding on this point we shall, wherever we are concerned not with the general spirit of disinterested inquiry but with slavish imitation of the method and language of Science, speak of “scientism” or the “scientistic” prejudice. Although these terms are not completely unknown in English, they are actually borrowed from the French, where in recent years they have come to be generally used in very much the same sense in which they will be used here. It should be noted that, in the sense in which we shall use these terms, they describe, of course, an attitude which is decidedly unscientific in the true sense of the word, since it involves a mechanical and uncritical application of habits of thought to fields different from those in which they have been formed. The scientistic as distinguished from the scientific view is not an unprejudiced but a very prejudiced approach which, before it has considered its subject, claims to know what is the most appropriate way of investigating it.
The book, though quite dense in parts, is really just plain brilliant from start to finish, and well worth the while of anyone interested in science and society.