Recent research has brought to light numerous facts that go against received views of the development of philosophy of science. One encounters several concepts, claims, or projects much earlier than is generally acknowledged. Auguste Comte was careful to distinguish each major science with respect to method and object, speaking of mathematical philosophy, biological philosophy, sociological philosophy, and so forth. He thereby in a sense anticipated the regionalist turn: philosophical analysis should be carried out with respect to a specific body of knowledge. He also adopted a general perspective, a scientific philosophy. In the light of new discoveries, later thinkers such as Pierre Duhem, Gaston Milhaud, and Abel Rey endeavored to reformulate Comte's doctrine as a neopositivism, a logical positivism, or an absolute positivism. The aim of this article is to examine the constitutive concepts mentioned and the controversies that hinge on them, in an effort to reach a precise understanding of the aim, scope, and import of philosophy of science in the context of nineteenth-century France.