Between 1926 and 1930, Schlick labored to finish Fragen der Ethik (Problems of Ethics), in which he surprised some of his fellow Circlists by including ethics as a viable branch of philosophy. In his 1932-33 contribution to Erkenntnis, "Positivism and Realism", Schlick offered one of the most illuminating definitions of positivism as every view "which denies the possibility of metaphysics" (Schlick, p. 260). Accordingly he defined metaphysics as the doctrine of “true being”, “thing in itself” or “transcendental being”, a doctrine which obviously "presupposes that a non-true, lesser or apparent being stands opposed to it"(Ibid). Therefore in this work he bases the positivism on a kind of epistemology which holds that the only true beings are givens or constituents of experience. Also during this time, the Vienna Circle published The Scientific View of the World: The Vienna Circle as a homage to Schlick. Its strong anti-metaphysical stance crystallized the viewpoint of the group.
Read more about this topic: Moritz Schlick