Richard Sieburth is Associate Professor of French, New York University.Gershom Scholem's contribution to the understanding of Jewish mysticism is so dramatic that it warrants a separate introduction. As a young student of mathematics, he became a Zionist and his interest shifted to Jewish history. Scholem moved from Germany to become the librarian of the new University and National Library in Jerusalem in 1923 and served as a professor at Hebrew University from 1935 to 1965. Before him, Jewish historians during the nineteenth and early twentieth centuries scorned the ignored mystical dimension of Judaism as a relic of premodern superstition and ignorance. Scholem's erudition and deep insight gave Cabala a scholarly audience. His writings are often difficult to read, but they are indispensable for any thorough knowledge of the subject of Jewish mysticism.