 As in the case of philosophy of psychology, Neurath’s philosophical theory of the social sciences was his attempt at a paradigmatic application of the logical empiricist framework that replaced philosophy as a speculative and autonomous source of knowledge. Philosophy was now the reflexive perspective of unified science and it was constituted by two meta-theoretical approaches to science: logical analysis and empirical theory, that is, the ‘logic of science’—emphasized by Carnap— and the ‘behavioristics of science’—emphasized by Neurath. The non-formal, empirical, perspective, allied to the ‘scientific attitude’, became in 1931 Neurath’s physicalism, his compromise between empiricism and materialism—Mach and Marx—; this was also his attempt at a resolution of the conflict between experience and objectivity (of scientific knowledge), which Carnap attempted through the formal aspect of structural descriptions and logical relations. 