dancer. However, critics differ on this interpretation, with the absence of modern urban amenities such as automobiles being noted. Cinema in Weimar culture did not shy away from controversial topics, but dealt with them explicitly. Diary of a Lost Girl (1929) directed by Georg Wilhelm Pabst and starring Louise Brooks, deals with a young woman who is thrown out of her home after having an illegitimate child, and is then forced to become a prostitute to survive. This trend of dealing frankly with provocative material in cinema began immediately after the end of the War. In 1919, Richard Oswald directed and released two films, that met with press controversy and action from police vice investigators and government censors. Prostitution dealt with women forced into "white slavery", while Different from the Others dealt with a homosexual man's conflict between his sexuality and social expectations; and in October 1920 censors ended its release to the public. By the end of the decade, similar material met with little, if any opposition when it was released in Berlin theatres. William Dieterle's Sex in Chains (1928), and Pabst's Pandora's Box (1929) deal with homosexuality among men and women, respectively, and were not censored. Homosexuality was also present more tangentially in other films from the period. Philosophy Philosophy during the Weimar Republic pursued paths of enquiry into scientific fields such as mathematics and physics. Leading scientists became associated as a group that was called the Berlin Circle. Among many influential thinkers, Carl Hempel was a strong influence in the group. Born in Berlin, Hempel attended the University of Göttingen and the University of Heidelberg, then returned to Berlin, where he was taught by influential physicists Hans Reichenbach and Max Planck, and logistics with mathematician John von Neumann. Reichenbach introduced Hempel to the Vienna Circle, who were an existing informal association of "scientifically interested philosophers and philosophically interested scientists", as Hempel put it. Hempel was intrigued by the logical positivism ideas discussed by the Vienna Circle, and he developed a similar network, the Berlin Circle. Hempel's reputation has grown to the extent that he is now considered one of the leading scientific philosophers of the 20th century. Richard von Mises was active in both groups. Germany's most influential philosopher during the Weimar Republic years, and perhaps of the 20th century, was Martin Heidegger. Heidegger published one of the cornerstones of 20th-century philosophy during this period, Being and