Thomas Aquinas Begins the Summa Theologica

The event

By the mid-thirteenth century, the rediscovery in Western Europe of Aristotle's philosophical works, transmitted in significant part through Arabic and Jewish scholarship, posed both an intellectual opportunity and a challenge for Christian theology: Aristotelian logic and natural philosophy offered powerful new analytical tools, but some of Aristotle's conclusions appeared to conflict with core Christian doctrines, prompting suspicion and even formal condemnation of certain Aristotelian propositions by church authorities.

Thomas Aquinas, a Dominican friar who had studied under Albertus Magnus, undertook to demonstrate that reason and revelation, philosophy and faith, were fundamentally compatible and mutually illuminating rather than opposed, beginning around 1265 the systematic project that became the Summa Theologica, intended originally as an introductory textbook for students of theology.

Organized into three major parts addressing God, the moral life and human action, and Christ and the sacraments, the Summa proceeds through thousands of individual questions, each structured through a rigorous scholastic method of stating objections, presenting a determination (often drawing on Aristotelian philosophy alongside scripture and earlier church authorities), and answering the initial objections — a method that became the definitive model of scholastic theological argument.

The work remained unfinished at Aquinas's death in 1274, following a mystical experience in late 1273 after which he reportedly stopped writing, considering everything he had produced "like straw" compared to what he had experienced. Though briefly controversial and even partially condemned by the Bishop of Paris in 1277, Aquinas's synthesis was progressively rehabilitated and, especially from the nineteenth century onward through papal endorsement (notably Leo XIII's 1879 encyclical Aeterni Patris), became the normative philosophical and theological framework of Catholic thought, an influence sometimes called Thomism that persists strongly in Catholic seminaries and universities to the present day.

Dating

Aquinas began the Summa around 1265-66 and left it unfinished at his death in 1274; the exact chronology of its composition across various teaching posts in Italy and Paris is reconstructed from internal and external evidence rather than precisely documented.

Other witnesses

• Thomas Aquinas, Summa Theologica (full text)

Further reading

• Christian History Magazine 73: Thomas Aquinas — free full issue
• The Summa Theologiae in English — primary source, complete
• Catholic Encyclopedia (1913): St. Thomas Aquinas