Rudolf Carnap was a leading member of the Vienna Circle and a major exponent of logical empiricism. The Vienna Circle was a group of scientists and philosophers who met in Vienna from the early 1920s to the late 1930s. Led by Moritz Schlick, Professor of the Philosophy of the Inductive Sciences at the University of Vienna, the Vienna Circle included the economist and sociologist Otto Neurath; the mathematicians Hans Hahn, Karl Menger, and Kurt Gödel; the physicist Philipp Frank; the historian and sociologist Edgar Zilsel; and the philosophers Friedrich Waissman, Felix Kaufmann, and Herbert Feigl. Inspired by the techniques of modern science and the development of mathematical logic, the Vienna Circle promoted a philosophical approach, known at first as logical positivism and later as logical empiricism, that aimed not at the establishment of truths about a realm of objects thought to be peculiar to philosophy but...