A Friar from Southern Italy
Thomas Aquinas was born around 1225 (the exact year is uncertain) at or near Roccasecca, in the Kingdom of Sicily, in what is now southern Italy. His family belonged to the local nobility. As a boy he was sent to the Benedictine abbey of Monte Cassino, where his relatives may have hoped he would one day become an abbot. He later studied at the university in Naples, where he came into contact with the Dominicans, a new order of preaching friars.
The Dominicans were founded in the early thirteenth century. Unlike monks who lived apart in rural abbeys, friars owned little, begged for support, and worked in towns and universities. Aquinas joined the order around the mid-1240s. According to traditional accounts, his family strongly objected, since a mendicant friar’s life seemed a poor fit for a noble son, and he was held at home for a time before being allowed to go. The details come from later biographies, so they are best taken as traditional rather than certain. The same caution applies to many stories about his life.
Study and Teaching
Aquinas went north to study, most notably under Albert the Great, a Dominican scholar who took a serious interest in the natural world and in the writings of Aristotle. Their time together in Paris and Cologne shaped Aquinas’s habit of reading Aristotle closely. Aristotle’s works had only recently become widely available in Latin, and many church authorities were unsure what to make of a pagan philosopher whose ideas sometimes seemed to clash with Christian belief.
In the 1250s Aquinas began teaching theology at Paris, and he became a master of theology there in 1256. Paris was the leading center of theological study, and its masters worked inside one of the early medieval universities, with its own rules, rivalries and disputes. Teaching in this setting meant lecturing on the Bible, commenting on a standard textbook of theology, and taking part in formal debates called disputed questions.
Aquinas did not stay in one place. Over the following years he taught in Paris, taught and served the order in Italy, and returned to Paris for a second term as master in the late 1260s. In the early 1270s he was at Naples. Much of his writing was done on the move, and he is said to have dictated to several secretaries at once, though this is a traditional report rather than a documented fact.
The Controversies Around Him
Aquinas worked during real disagreements about how far philosophy should be allowed to shape theology. Some thinkers thought Aristotle should be kept out of the faculty of theology; others pushed Aristotle’s ideas in ways Aquinas himself rejected. He defended a middle path: that reason and revelation can both lead to truth, and so do not truly contradict each other. This question of faith and reason runs through all his major works.
His approach was not accepted by everyone. In 1277, a few years after his death, church authorities in Paris and Oxford condemned a list of propositions, and some of them touched views associated with him. Over the following decades his reputation recovered, and the Dominican order came to treat his teaching as a standard. He was declared a saint in 1323.
Major Works
Aquinas wrote a great deal. Besides commentaries on the Bible and on Aristotle, his best-known writings include:
- Commentaries on the Sentences, the textbook that medieval theology students were expected to study.
- The Summa contra Gentiles, a long work that sets out Christian teaching in an orderly argument.
- Disputed questions on topics such as truth and the power of God.
- The Summa Theologiae, his last and most famous project.
Besides these, he wrote short works, sermons, and texts for the liturgy, though attributions for some of the smaller pieces are debated.
How the Summa Theologiae Is Organized
The Summa Theologiae was begun around the mid-1260s and was intended as a guide for students who needed a clear introduction to theology. A “summa” simply means a summary or comprehensive treatment, and the work is enormous. Its structure is one of its most distinctive features.
At the top level it has three parts. The first part deals with God and with the creation of the world, including angels and human nature. The second part, which is so long that it is traditionally split into two sections, turns to human action: happiness, the virtues and vices, law and grace, and then specific moral topics in more detail. The third part concerns Christ, the sacraments, and the end of human life. It was left unfinished, and a later supplement was assembled by others from his earlier writings to cover the remaining topics.
Each part is divided into questions, and each question into articles. The articles all follow the same pattern, which is a compact version of the scholastic method used in medieval schools:
- A question is posed, usually in yes-or-no form, such as whether God exists.
- Several objections are stated, often fairly and at length.
- A short “on the contrary” quotes a respected authority in support of the other side.
- Aquinas gives his own answer, which explains his reasoning.
- He then responds to each objection in turn.
This format makes the Summa easier to navigate than it first appears, because any single article can be read on its own. It also shows how medieval teaching worked: opposing views were laid out before a conclusion was reached, which was the habit of the lecture hall and the disputation.
One well-known passage in the first part presents five arguments for the existence of God, usually called the “five ways.” They are very brief, and they sit in a work whose real focus is much broader.
The Unfinished End
In December 1273, according to traditional accounts, Aquinas stopped writing after a deeply affecting experience while celebrating Mass. He is reported to have said that what he had written seemed like straw compared with what he had seen. Historians cannot reconstruct what happened, and the story comes from people who knew him; it should be treated with care. What is certain is that the Summa Theologiae was left incomplete.
In early 1274 he set out for the Council of Lyon, but fell ill on the journey and died on March 7 at the abbey of Fossanova, south of Rome. He was probably around fifty.
Aquinas in Context
Aquinas lived in the same wider world as other well-known figures of his century, such as Francis of Assisi, who founded the Franciscan order (a rival mendicant movement with its own style of theology). Later, poets such as Dante drew on his thinking when composing the Divine Comedy. His main philosophical rivals included thinkers from the Franciscan tradition, such as Duns Scotus, who disagreed with him on several questions.
In later centuries, especially from the late nineteenth century onward, the Catholic Church gave his writings an unusually prominent place in its schools. Outside the church, scholars still study him as a major figure in the history of philosophy. That long afterlife is part of why a medieval friar who died in his forties or fifties still has so much written about him.