Lev Isaakovich Shestov (Лев Исаа́кович Шесто́в; 31 January [O.S. 13 February] 1866 – 19 November 1938), born Yeguda Leib Shvartsman (Иегуда Лейб Шварцман), was a Russian existentialist and religious philosopher. He is best known for his critiques of both philosophic rationalism and positivism. His work advocated a movement beyond reason and metaphysics, arguing that these are incapable of conclusively establishing truth about ultimate problems, including the nature of God or existence. Contemporary scholars have associated his work with the label "anti-philosophy." Shestov wrote extensively on philosophers such as Nietzsche and Kierkegaard, as well as Russian writers such as Dostoyevsky, Tolstoy, and Chekhov. His published books include Apotheosis of Groundlessness (1905) and his magnum opus Athens and Jerusalem (1930-37). After emigrating to France in 1921, he befriended and influenced thinkers such as Edmund Husserl, Benjamin Fondane, Rachel Bespaloff, and Georges Bataille. He lived in Paris until his death in 1938. Shestov was born Yeguda Leib Shvartsman in Kyiv into a Jewish family. He was a cousin of Nicholas Pritzker, a lawyer who emigrated to Chicago and became the patriarch of the Pritzker family that is prominent in business and politics. He obtained an education at various places, due to fractious clashes with authority. He went on to study law and mathematics at the Moscow State University but after a clash with the Inspector of Students he was told to return to Kyiv, where he completed his studies. Shestov's dissertation was rejected by the St. Vladimir's Imperial University of Kyiv on account of the revolutionary tendencies it express, thus preventing him from becoming a doctor of law. In 1898 he entered a circle of prominent Russian intellectuals and artists which included Nikolai Berdyaev, Sergei Diaghilev, Dmitri Merezhkovsky and Vasily Rozanov. Shestov contributed articles to a journal the circle had established.