This book demonstrates that the four recognized founders of scientific sociology were by no means "value-free"-but rather that each held a clear vision informing, either explicitly or implicitly, the work of the classical sociologists by establishing norms for their analyses of social relations. The author has ferreted out each thinker's concept of ideal man by reviewing all their writings in French, Italian, and German. He also has found the influences-intellectual, social, and psychological-affecting the classical sociologists' views of mankind, by studying masses of biographical data on them. Thus the book is a contribution to the social psychology of knowledge in two ways: first, in tracing the taproots of classical sociological ideas; second, in tracing the ramifications of those ideas in systems that have had profound effects on the thinking of others.