Ernst Bloch was one of the most significant twentieth-century German thinkers, yet he remains overshadowed by his Frankfurt School contemporaries. Known for his engagement with utopianism and religious thought, Bloch also wrote incisively about ontological questions. In his short masterpiece Avicenna and the Aristotelian Left, Bloch gives a striking account of materialism that traces emancipatory elements of modern thought to medieval Islamic philosophers’ encounter with Aristotle.