Vienna Circle
Authors: Stadler Friedrich 
Published: September 2018

The Vienna Circle was a group of about three dozen thinkers drawn from the natural and social sciences, logic and mathematics who met regularly in Vienna between the wars to discuss philosophy. The work of this group constitutes one of the most important and most influential philosophical achievements of the twentieth century, especially in the development of analytic philosophy and philosophy of science.
The Vienna Circle made its first public appearance in 1929 with the publication of its manifesto, The Scientific Conception of the World: The Vienna Circle (Carnap, Hahn and Neurath 1929). At the centre of this modernist movement was the so-called ‘Schlick Circle’, a discussion group organized in 1924 by the physics professor Moritz Schlick. Friedrich Waismann, Herbert Feigl, Rudolf Carnap, Hans Hahn, Philipp Frank, Otto Neurath, Viktor Kraft, Karl Menger, Kurt Gödel and Edgar Zilsel belonged to this inner circle. Their meetings in the Boltzmanngasse were also attended by Olga Taussky-Todd, Olga Hahn-Neurath, Felix Kaufmann, Rose Rand, Gustav Bergmann and Richard von Mises, and on some occasions by visitors from abroad such as Hans Reichenbach, Alfred Ayer, Ernest Nagel, Willard Van Orman Quine and Alfred Tarski. This discussion circle was pluralistic and committed to the ideals of the Enlightenment. It was unified by the aim of making philosophy scientific with the help of modern logic on the basis of scientific and everyday experience. At the periphery of the Schlick Circle, and in a more or less strong osmotic contact with it, there were loose discussion groups around Ludwig Wittgenstein, Heinrich Gomperz, Richard von Mises and Karl Popper. In addition the mathematician Karl Menger established in the years 1926–36 an international mathematical colloquium, which was attended by Kurt Gödel, John von Neumann and Alfred Tarski among others.
Thus the years 1924–36 saw the development of an interdisciplinary movement whose purpose was to transform philosophy. Its public profile was provided by the Ernst Mach Society through which members of the Vienna Circle sought to popularize their ideas in the context of programmes for national education in Vienna. The general programme of the movement was reflected in its publications, such as the journal Erkenntnis (‘Knowledge’, later called The Journal for Unified Science), and the International Encyclopedia of Unified Science. Given this story of intellectual success, the fate of the Vienna Circle was tragic. The Ernst Mach Society was suspended in 1934 for political reasons, Moritz Schlick was murdered in 1936, and around this time many members of the Vienna Circle left Austria for racial and political reasons; thus soon after Schlick’s death the Circle disintegrated. As a result of the emigration of so many of its members, however, the characteristic ideas of the Vienna Circle became more and more widely known, especially in Scandinavia, Britain and North America where they contributed to the emergence of modern philosophy of science. In Germany and Austria, however, the philosophical and mathematical scene was characterized by a prolongation of the break that was caused by the emigration of the members of the Vienna Circle.