The Summa Theologica, Part I

The Summa Theologica is the most influential work of systematic Christian theology ever written. Thomas Aquinas, a Dominican friar and the most accomplished philosophical theologian of the High Middle Ages, composed it as a comprehensive teaching manual for students of theology. He worked on it for the last seven years of his life and left it unfinished at his death in 1274.

This volume contains Prima Pars (Part I) — on the existence and nature of God, the creation of the world, the angels, and the nature and powers of the human being made in God's image. It contains the famous "Five Ways" of demonstrating the existence of God — the most-discussed argument for God's existence in Western philosophy.