 If sociology merges at places with philosophy, it is also closely related to history. Comte was thus led to take a stand on a question that deeply divides us today: how should the relations among philosophy of science, history of science, and sociology of science be seen? In the Course, history is at once everywhere and nowhere: it is not a discipline, but the method of sociology. Dynamic sociology is ‘a history without names of men, or even of people’ (1830 (52), v. 2, 239). It is easy to understand, then, that positivism has always refused to separate the philosophy of science from the history of science. According to positivism, one does not really know a science until one knows its history; indeed, it was a chair in the general history of science that Comte had asked Guizot to create for him at the Collège de France. Mill’s position was not quite the same, for he took the author of the Course to task for neglecting the production of proof, or, to use modern vocabulary, for being more interested in the context of discovery than in the context of justification (Mill 1865). The criticism is only partly legitimate: from the second lesson in the Course, Comte carefully distinguishes between the doctrinal and the historical study of science, opting for the first while leaving the second for the lessons in sociology. Just as for Comte the philosophy of science is not a philosophy of nature but of the mind, he likewise values the history of science less as a subject in its own right than as the ‘most important, yet so far most neglected part’ of the development of Humanity (1830 (2), v. 1, 53). Each science is therefore examined twice in the Course: for its own sake, in the first three volumes; in its relations to the general development of society, in the final three. In this way, Comte succeeds in reconciling the internalist and externalist points of view, usually considered to be incompatible.