   During the same period, Rudolf Carnap joined the faculty of the University of Vienna as well as the Schlick Zirkel. He brought a manuscript with him, which he called “Konstitutionstheorie”, and which was eventually published, with Schlick’s help, as The Logical Structure of the World (Carnap 1928). Schlick even assisted Carnap in locating a publisher for the work. It was at this time that Schlick penned the essay “Experience, Cognition, and Metaphysics” of 1926, which represents a particularly important juncture in his thinking. Schlick attempted to link current influences on his thought – Wittgenstein’s Tractatus  and Carnap’s Aufbau – with his earlier ideas, especially the distinction between intuitions and concepts (Schlick 2008, pp. 33–56; Wittgenstein 1961; Carnap 1928; Schlick 2009, Sec. 7). 