Thomas Aquinas is one of the most important thinkers of the High Middle Ages. A pivotal figure in the transition from the Ancient to the Modern eras in Philosophy, he also had a lasting influence on Christian Theology that endures to this day. Covering his life, times, ideas, work and legacy, The Bloomsbury Companion to Aquinas is a complete one-volume reference guide to this important thinker. Historical essays explore not only Aquinas's life and times but also the key influences on his thought, from Aristotle to his contemporaries and the most important critics and commentators to have followed him. An extensive A-Z of key terms and critical synopses of his major works provide a comprehensive and accessible overview of Aquinas' thought. The final section charts the development of Aquinas's legacy, from the First Thomism of the 13th century to contemporary Existential and Analytical Thomism. Thoroughly indexed and cross-referenced throughout, with extensive guides to key secondary readings, The Bloomsbury Companion to Aquinas is an indispensable reference resource for those working in Philosophy, Theology or Medieval Thought.