 To begin with, in their 1931 article “Logical Positivism: A New Movement in European Philosophy,” Feigl and Blumberg presented the logical positivist approach as the synthesis of two “significant traditions” (Feigl/Blumberg 1931, p. 281): the classical “positivistic-empirical” current in European philosophy, and the development of modern (mathematical) logic. The most characteristic feature of the emerging “new movement” was, according to Feigl and Blumberg, its conception of the propositions of metaphysics as “meaningless” (ibid., p. 282). This diagnosis also pertained to Kant’s account of synthetic a priori judgments, the existence of which was explicitly contested. However, it must be seen that Feigl never went as far as to reject the analytic/synthetic distinction as such. As he later argued against Quine, “[t]he revolt against the dualism of the analytic and the synthetic rests on a confusion of the logical analysis of (artificially fixed) languages with the historical investigation of (growing, shifting natural) languages” (Feigl 1956, p. 7–8). Thus, in the logical positivist account, analytic propositions had to be sharply distinguished from synthetic propositions. Whereas the latter had their place in experience and experiential science, the former belonged to logic and mathematics. More precisely, Feigl and Blumberg agreed with Wittgenstein that logic, by its very nature, is purely tautological. It has nothing to do with experience, but only with the internal structure of language. Here, they saw the principle advantage over previous, traditional, empiricist accounts of logic and mathematics. Moreover, Feigl and Blumberg maintained that even the concepts of the empirical sciences are such as can be subject to a purely formal, logical, reconstruction. Relying on a principled distinction between “knowledge proper” (Erkenntnis) and objectivity, on the one hand, and “immediate experience” (Erlebnis) and subjectivity, on the other, they referred the reader to Carnap’s Der logische Aufbau der Welt, thereby implying that a constitution of empirical concepts from a single primitive relation, namely that of “Ähnlichkeitserinnerung”, by “purely logical operations” (Feigl/Blumberg 1931, p. 286) was at least in sight. The essential point in this connection was that the propositions of empirical science were supposed to be translatable into a series of propositions which exclusively referred to structural features of experience, but not to the experientially given itself (which was conceived of as completely subjective and thus ‘private’). It was therefore structure which stood in the focus of the respective reconstruction of empirical knowledge. Knowledge, according to Feigl and Blumberg, is to be defined as “the communicable” (ibid.) and “[w]hat knowledge communicates is structure […].” (ibid.)