Philosopher, Theologian, and Roman Catholic Saint. He was an Italian Dominican friar and priest and an immensely influential philosopher and theologian in the tradition of scholasticism, a method of critical thought that dominated teachings by the academics of medieval universities during the Middle Ages. He was the foremost classical proponent of natural theology, and the father of Thomism, the philosophical school that arose as a legacy of his work. Born into a southern Italian nobility family on January 28, 1225, he began his early education when he was five years old at Monte Cassino, and in 1239 he was enrolled at the University of Naples, which was established by Emperor Frederick II at Naples, Italy. During his time at Naples, he came under the influence of John of St. Julian, a Dominican preacher who was part of the active effort by the Dominican order to recruit devout followers. At the age of nineteen, he joined the recently founded Dominican Order, which did not please his family. In an attempt to prevent his mother's interference in his choice, the Dominicans arranged to move him to Rome, Italy and from there to Paris, France. However, while on his journey to Rome, his brothers abducted him and took him back to his parents at the castle of Monte San Giovanni Campano and held him prisoner for about a year. Seeing that all attempts to dissuade him had failed, his mother sought to save the family's dignity and arranged for him to escape at night through his window. He was sent first to Naples and then to Rome to meet Johannes von Wildeshausen, the Master General of the Dominican Order. In 1245 he was sent to study at the Faculty of the Arts at the University of Paris, where he most likely met Dominican scholar Albertus Magnus, then the Chair of Theology at the College of St. James in Paris. In 1248 he declined Pope Innocent IV's offer to appoint him abbot of Monte Cassino as a Dominican and accompanied Albertus who was sent to teach at the new university at Cologne, Germany, where he taught as an apprentice professor. In 1250 he became a priest and in 1252 he returned to Paris to study for his Master's Degree in Theology. He lectured on the Bible as an apprentice professor, and upon becoming a bachelor of the Sentences, he devoted his final three years of study to commenting on Peter Lombard's "Four Books of Sentences." In the first of his four theological syntheses, he composed a massive commentary on the Sentences entitled "Scriptum super libros Sententiarium" (Commentary on the Sentences). Aside from his Masters writings, he wrote "De ente et essential" (On Being and Essence) for his fellow Dominicans in Paris. In the spring of 1256, he was appointed Regent Master in Theology at Paris and one of his first works upon assuming this office was "Contra impugnantes Dei cultum et religionem" (Against Those Who Assail the Worship of God and Religion). During his tenure from 1256 to 1259, he wrote numerous works, including "Questiones disputatae de veritate" (Disputed Questions on Truth), a collection of 29 disputed questions on aspects of faith and the human condition prepared for the public university debates he presided over on Lent and Advent, "Questiones quodlibetales" (Quodlibetal Questions), a collection of his responses to questions posed to him by the academic audience, and both "Expositio super librum Boethii De trinitate" (Commentary on Boethius's De trinitate) and "Expositio super librum Boethii De hebdomadibus" (Commentary on Boethius's De hebdomadibus), commentaries on the works of 6th-century philosopher Anicius Manlius Severinus Boethius. By the end of his regency, he was working on one of his most famous works, "Summa contra Gentiles." In 1259 he returned to Naples where the following year he was appointed as general preacher. In September 1261 he was called to Orvieto as the lector responsible for the pastoral formation of the friars unable to attend a university. There he completed his "Summa contra Gentiles," wrote the "Catena aurea," (The Golden Chain), and produced works for Pope Urban IV such as the liturgy for the newly created feast of Corpus Christi and the "Contra errores graecorum" (Against the Errors of the Greeks). In February 1265 the newly elected Pope Clement IV summoned him to Rome to serve as papal theologian and in the same year he was ordered by the Dominican Chapter of Agnani to teach at the university at the Roman convent of Santa Sabina. While there, he began his most famous work, the "Summa Theologica." In 1268 he returned to Paris for a second teaching regency, a position he held until 1272. During this time, he completed the second part of his "Summa Theologica" and wrote "De virtutibus" and "De aeternitate mundi," the latter of which dealt with controversial Averroist and Aristotelian "beginninglessness" of the world. In 1272 he took leave from the University of Paris when the Dominicans from his home province called upon him to establish a university wherever he liked and staff it as he pleased. He chose to establish the institution in Naples, and moved there to take his post as regent master and worked on the third part of the "Summa Theologica" while giving lectures on various religious topics. On May 1, 1274 Pope Gregory X planned to convene the Second Council of Lyon, in an effort to reunite the Eastern Orthodox Church and the Roman Catholic Church, and summoned him to attend. On his way to the Council, he struck his head on the branch of a fallen tree and became seriously ill and was taken to Monte Cassino to recover. After resting for a while, he set out again, but stopped at the Cistercian Fossanova Abbey, after becoming ill again, he died at the age of 49. On July 18, 1323, 50 years after his death, he was pronounced a saint by Pope John XXII and in 1567 he was declared a Doctor of the Catholic Church. In 1369 his remains, with the exception of the thumb of his right hand, were interred at the Church of the Jacobins in Toulouse, France. In 1880 he was declared the patron saint of all Roman Catholic educational establishments, academics, students, philosophers, theologians, and book sellers. He is honored with a feast day on January 28 in the Roman Catholic Church and in the liturgical year of the Episcopal Church in the US.