Johann Nelböck

In 1951, Nelböck sued Victor Kraft, a member of the Vienna Circle, who had called Nelböck a "paranoid psychopath" in his (Kraft's) book Der Wiener Kreis. Kraft agreed to an out-of-court settlement.

From 1938 on, Nelböck worked in the geological department of the wartime economic oil authority. When the period of probation ended in 1943, he worked as a technical employee in the Main Measurement Office.

On May 26, 1937, Nelböck was sentenced to ten years' imprisonment, but only two years later - after the annexation of Austria into Nazi Germany in 1938 - asked for a pardon. In his application he pointed out "that by his act and the result elimination of a Jewish teacher who propagated doctrines alien and detrimental to the nation he rendered National Socialism a service and also suffered for National Socialism as a consequence of his act. Since the world-view, the rightness of which he recognized even then and out of which he committed his act, is now the ruling national ideology, he considers it a hardship if he still has to remain in a disadvantaged position because of an act which sprang from his world-view." Because the Senior Public Prosecutor concluded that Nelböck's act was accompanied primarily by personal motives, Nelböck was only released on probation on October 11, 1938.

On June 22, 1936, Nelböck shot Schlick in the chest, killing him on one of the central staircases of the University of Vienna. The substantiation of the judgment of the Provincial Court for Criminal Matters of Vienna (dated May 26, 1937) summed up:

After attending the gymnasium in Wels, Nelböck studied philosophy at the University of Vienna from 1925 on with Moritz Schlick, who was his doctoral advisor, and graduated as a Doctor of Philosophy on March 21, 1931, with the doctoral thesis "The Importance of Logic in Empirism and Positivism". Twice Nelböck was sent to a mental hospital with the diagnosis of schizoid personality disorder. He had threatened to kill Schlick.

Johann "Hans" Nelböck (May 12, 1903 – February 3, 1954) was an Austrian former student and murderer of Moritz Schlick, the founder of the group of philosophers and scientists known as the Vienna Circle.