This concise book tells the story of the most important theological work of the Middle Ages, the vast Summa theologiae of Thomas Aquinas, which holds a unique place in Western religion and philosophy. Written between 1266 and 1273, the Summa was conceived by Aquinas as an instructional guide for teachers and novices and a compendium of all the approved teachings of the Catholic Church. It synthesizes an astonishing range of scholarship,...