The Summa Theologiae (written 1265-1274 and also known as the Summa Theologica or simply the Summa) is the best-known work of Thomas Aquinas (c. 1225-1274). Although unfinished, the Summa is "e;one of the classics of the history of philosophy and one of the most influential works of Western literature."e; It was intended as an instructional guide for theology students, including seminarians and the literate laity. It was a compendium of all of the main theological teachings of the Catholic Church. It presents the reasoning for almost all points of Christian theology in the West. The Summa's topics follow a cycle: the existence of God; Creation, Man; Man's purpose; Christ; the Sacraments; and back to God.