Moritz Schlick

German philosopher, physicist, and the founding father of logical positivism and the Vienna Circle. Early members of this Circle included the mathematician Hans Hahn and, within a few years, Rudolf Carnap, Herbert Feigl, Kurt Gödel, Otto Neurath, Friedrich Waismann and others.

With the rise of the Nazis in Germany and Austrofascism in Austria, many of the Vienna Circle's members left for the United States and the United Kingdom. Schlick, however, stayed on at the University of Vienna. When visited by Feigl in 1935, he expressed dismay at events in Germany. On 22 June 1936, Schlick was ascending the steps of the University for a class when he was confronted by a former student, Johann Nelböck, who killed him with a pistol. After the annexation of Austria into Nazi Germany in 1938 the assassin was released on probation after serving two years of a 10-year sentence.