Logical Positivism

In the years prior to World War I, a mathematician, a sociologist, and a physicist would come together regularly to meet in various cafés around Vienna, Austria, to discuss philosophy in a genial, friendly atmosphere. At the core of the majority of their discussions was the nature of belief—a field of philosophy called epistemology. How do we know “truth” from “fiction”? This issue is at the heart of attempts to define truth, whether from a scientific or a communication point of view.

The war put a temporary hold on their association as the group disbanded and went their separate ways. It wasn't until 1922 that the mathematician Hans Hahn returned to Vienna and encouraged a newly appointed professor in the philosophy of inductive sciences to join him in rekindling the old discussions. This gentleman, a German by the name of Moritz Schlick, had published on a range of topics, from the novel special theory of relativity to the nature of truth and logic. It was with this association that the Vienna Circle was formed.

With Schlick as chairman, this gathering formally established itself in 1928 as the Ernst Mach Society, honoring the Austrian physicist and philosopher who had famously described the descriptions of natural laws as summaries of experimental data. The members of this society, including the original members Hahn, Otto Neurath, and Phillip [Page 447]Frank, included mathematicians, philosophers, and physicists such as Kurt Gödel, Gustav Bergmann, Rudolf Carnap, Richard Edler von Mises, and Hahn's sister (and Otto Neurath's wife) Olga. Mach's influence was clearly reflected in a common philosophy shared by most members of the society—one that valued empiricism and logic in evaluating the strength of ideas.

In 1929, a pamphlet titled “The Scientific Conception of the World—The Vienna Circle” was printed, listing the members of the circle in an appendix at the back. This pamphlet became better known as the “Vienna Circle Manifesto,” and within it was an attempt to define the characteristics of the scientific method.