With extraordinary chutzpa and deep philosophical seriousness, Solomon ben Joshua of Lithuania renamed himself after his medieval intellectual hero, Moses Maimonides. Maimon was perhaps the most brilliant and certainly the most controversial figure of the late-eighteenth century Jewish Enlightenment. He scandalized rabbinic authorities, embarrassed Moses Mendelssohn, provoked Kant, charmed Goethe, and inspired Fichte, among others. This is the first study of Maimon to integrate his idiosyncratic philosophical idealism with his popular autobiography, and with his early unpublished exegetical, mystical, and Maimonidean work in Hebrew. In doing so, it illuminates the intellectual and spiritual possibilities open to a European Jew at the turn of the eighteenth century.