Thomas Aquinas, (Italian: Tommaso d’Aquino, lit. ‘Thomas of Aquino; 1225 – 7 March 1274), was an Italian Dominican friar, Catholic priest, and Doctor of the Church. He was an immensely influential philosopher, theologian, and jurist in the tradition of scholasticism, within which he is also known as the Doctor Angelicus and the Doctor Communis. The name Aquinasidentifies his ancestral origins in the county of Aquino in present-day Lazio, where his family held land until 1137.
He was the foremost classical proponent of natural theology and the father of Thomism. His influence on Western thought is considerable, and much of modern philosophy developed or opposed his ideas, particularly in the areas of ethics, natural law, metaphysics, and political theory. Unlike many currents in the Church of the time, Thomas embraced several ideas put forward by Aristotle—whom he called “the Philosopher”—and attempted to synthesize Aristotelian philosophy with the principles of Christianity. The works for which he is best known are the Summa Theologiae and the Summa contra Gentiles. His commentaries on Scripture and on Aristotle form an important part of his body of work. Furthermore, Thomas is distinguished for his eucharistic hymns, which form a part of the Church’s liturgy.
The Catholic Church honors Thomas Aquinas as a saint and regards him as the model teacher for those studying for the priesthood, and indeed the highest expression of both natural reason and speculative theology. In modern times, under papal directives, the study of his works was long used as a core of the required program of study for those seeking ordination as priests or deacons, as well as for those in religious formation and for other students of the sacred disciplines (philosophy, Catholic theology, church history, liturgy, and canon law).
Thomas Aquinas is considered one of the Catholic Church’s greatest theologians and philosophers. Pope Benedict XV declared: “This (Dominican) Order … acquired new luster when the Church declared the teaching of Thomas to be her own and that Doctor, honored with the special praises of the Pontiffs, the master and patron of Catholic schools.”
Table of Contents
Early life (1225–1244)
Thomas was most probably born in the castle of Roccasecca, located in Aquino, old county of the Kingdom of Sicily (present-day Lazio region, Italy), c.1225. He was born in the castle of his father, Landulf of Aquino. Though he did not belong to the most powerful branch of the family, Landulf of Aquino was a man of means. As a knight in the service of King Roger II of Sicily, he held the title miles. Thomas’ mother, Theodora, belonged to the Rossi branch of the Neapolitan Caracciolo family. Landulf’s brother Sinibald was abbot of the first Benedictine monastery at Montecassino. While the rest of the family’s sons pursued military careers, the family intended for Thomas to follow his uncle into the abbacy; This would have been a normal career path for a younger son of southern Italian nobility.
At the age of five Thomas began his early education at Monte Cassino but after the military conflict between the Emperor Frederick II and Pope Gregory IX spilled into the abbey in early 1239, Landulf and Theodora had Thomas enrolled at the studium generale (university) recently established by Frederick in Naples. It was here that Thomas was probably introduced to Aristotle, Averroes and Maimonides, all of whom would influence his theological philosophy. It was also during his study at Naples that Thomas came under the influence of John of St. Julian, a Dominican preacher in Naples, who was part of the active effort by the Dominican order to recruit devout followers. There his teacher in arithmetic, geometry, astronomy, and music was Petrus de Ibernia.
At the age of nineteen Thomas resolved to join the recently founded Dominican Order. Thomas’ change of heart did not please his family. In an attempt to prevent Theodora’s interference in Thomas’ choice, the Dominicans arranged to move Thomas to Rome, and from Rome, to Paris. However, while on his journey to Rome, per Theodora’s instructions, his brothers seized him as he was drinking from a spring and took him back to his parents at the castle of Monte San Giovanni Campano.
Thomas was held prisoner for about one year in the family castles at Monte San Giovanni and Roccasecca in an attempt to prevent him from assuming the Dominican habit and to push him into renouncing his new aspiration. Political concerns prevented the Pope from ordering Thomas’ release, which had the effect of extending Thomas’ detention. Thomas passed this time of trial tutoring his sisters and communicating with members of the Dominican Order. Family members became desperate to dissuade Thomas, who remained determined to join the Dominicans. At one point, two of his brothers resorted to the measure of hiring a prostitute to seduce him. According to legend Thomas drove her away wielding a fire iron. That night two angels appeared to him as he slept and strengthened his determination to remain celibate.
By 1244, seeing that all of her attempts to dissuade Thomas had failed, Theodora sought to save the family’s dignity, arranging for Thomas to escape at night through his window. In her mind, a secret escape from detention was less damaging than an open surrender to the Dominicans. Thomas was sent first to Naples and then to Rome to meet Johannes von Wildeshausen, the Master General of the Dominican Order.
Paris, Cologne, Albert Magnus, and first Paris regency (1245–1259)
In 1245 Thomas 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. When Albertus was sent by his superiors to teach at the new studium generale at Cologne in 1248, Thomas followed him, declining Pope Innocent IV’s offer to appoint him abbot of Montecassino as a Dominican. Albertus then appointed the reluctant Thomas magister studentium. Because Thomas was quiet and didn’t speak much, some of his fellow students thought he was slow. But Albertus prophetically exclaimed: “You call him the dumb ox, but in his teaching he will one day produce such a bellowing that it will be heard throughout the world.”
Thomas taught in Cologne as an apprentice professor (baccalaureus biblicus), instructing students on the books of the Old Testament and writing Expositio super Isaiam ad litteram (Literal Commentary on Isaiah), Postilla super Ieremiam (Commentary on Jeremiah) and Postilla super Threnos (Commentary on Lamentations). Then in 1252 he returned to Paris to study for the master’s degree in theology. He lectured on the Bible as an apprentice professor, and upon becoming a baccalaureus Sententiarum (bachelor of the Sentences) devoted his final three years of study to commenting on Peter Lombard’s Sentences. In the first of his four theological syntheses, Thomas 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 essentia (On Being and Essence) for his fellow Dominicans in Paris.
In the spring of 1256 Thomas 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), defending the mendicant orders, which had come under attack by William of Saint-Amour. During his tenure from 1256 to 1259, Thomas wrote numerous works, including: Questiones disputatae de veritate (Disputed Questions on Truth), a collection of twenty-nine disputed questions on aspects of faith and the human condition prepared for the public university debates he presided over on Lent and Advent; Quaestiones 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’ De trinitate) and Expositio super librum Boethii De hebdomadibus (Commentary on Boethius’ De hebdomadibus), commentaries on the works of 6th-century Roman philosopher Boethius. By the end of his regency, Thomas was working on one of his most famous works, Summa contra Gentiles.
Naples, Orvieto, Rome (1259–1268)
In 1259 Thomas completed his first regency at the studium generale and left Paris so that others in his order could gain this teaching experience. He returned to Naples where he was appointed as general preacher by the provincial chapter of 29 September 1260. In September 1261 he was called to Orvieto as conventual lector responsible for the pastoral formation of the friars unable to attend a studium generale. In Orvieto Thomas 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). Some of the hymns that Thomas wrote for the feast of Corpus Christi are still sung today, such as the Pange lingua, Tantum ergo, and Panis angelicus. Modern scholarship has confirmed that Thomas was indeed the author of these texts, a point that some had contested.
In February 1265 the newly elected Pope Clement IV summoned Aquinas to Rome to serve as papal theologian. This same year he was ordered by the Dominican Chapter of Agnani to teach at the studium conventuale at the Roman convent of Santa Sabina, founded some years before, in 1222. The studium at Santa Sabina now became an experiment for the Dominicans, the Order’s first studium provinciale, an intermediate school between the studium conventuale and the studium generale. Prior to this time the Roman Province had offered no specialized education of any sort, no arts, no philosophy; only simple convent schools, with their basic courses in theology for resident friars, were functioning in Tuscany and the meridionale during the first several decades of the order’s life. But the new studium at Santa Sabina was to be a school for the province”, a studium provinciale. Tolomeo da Lucca, an associate and early biographer of Aquinas, tells us that at the Santa Sabina studium Aquinas taught the full range of philosophical subjects, both moral and natural.
While at the Santa Sabina studium provinciale Thomas began his most famous work, the Summa theologiae, which he conceived of specifically as suited to beginning students: “Because a doctor of Catholic truth ought not only to teach the proficient, but to him pertains also to instruct beginners. As the Apostle says in 1 Corinthians 3:1–2, as to infants in Christ, I gave you milk to drink, not meat, our proposed intention in this work is to convey those things that pertain to the Christian religion in a way that is fitting to the instruction of beginners.” While there he also wrote a variety of other works like his unfinished Compendium Theologiae and Responsio ad fr. Ioannem Vercellensem de articulis 108 sumptis ex opere Petri de Tarentasia (Reply to Brother John of Vercelli Regarding 108 Articles Drawn from the Work of Peter of Tarentaise). In his position as head of the studium Aquinas conducted a series of important disputations on the power of GOD, which he compiled into his De potentia. Nicholas Brunacci [1240–1322] was among Aquinas’ students at the Santa Sabina studium provinciale and later at the Paris studium generale. In November 1268 he was with Aquinas and his associate and secretaryReginald of Piperno, as they left Viterbo on their way to Paris to begin the academic year. Another student of Aquinas’ at the Santa Sabina studium provinciale was Blessed Tommasello da Perugia.
Aquinas remained at the studium at Santa Sabina from 1265 until he was called back to Paris in 1268 for a second teaching regency. With his departure for Paris in 1268 and the passage of time the pedagogical activities of the studium provinciale at Santa Sabina were divided between two campuses. A new convent of the Order at the Church of Santa Maria sopra Minerva had a modest beginning in 1255 as a community for women converts, but grew rapidly in size and importance after being given over to the Dominicans friars in 1275. In 1288 the theology component of the provincial curriculum for the education of the friars was relocated from the Santa Sabina studium provinciale to the studium conventuale at Santa Maria sopra Minerva, which was redesignated as a studium particularis theologiae. This studium was transformed in the 16th century into the College of Saint Thomas (Latin: Collegium Divi Thomæ). In the 20th century the college was relocated to the convent of Saints Dominic and Sixtus and was transformed into the Pontifical University of Saint Thomas Aquinas, Angelicum.
Quarrelsome second Paris regency (1269–1272)
In 1268 the Dominican order assigned Thomas to be regent master at the University of Paris for a second time, a position he held until the spring of 1272. Part of the reason for this sudden reassignment appears to have arisen from the rise of “Averroism” or “radical Aristotelianism” in the universities. In response to these perceived evils, Thomas wrote two works, one of them being De unitate intellectus, contra Averroistas (On the Unity of Intellect, against the Averroists) in which he blasts Averroism as incompatible with Christian doctrine. During his second regency, he finished the second part of the Summa and wrote De virtutibus and De aeternitate mundi, the latter of which dealt with controversial Averroist and Aristotelianbeginninglessness of the world.
Disputes with some important Franciscans such as Bonaventure and John Peckham conspired to make his second regency much more difficult and troubled than the first. A year before Thomas re-assumed the regency at the 1266–67 Paris disputations, Franciscan master William of Baglione accused Thomas of encouraging Averroists, calling him the “blind leader of the blind”. Thomas called these individuals the murmurantes(Grumblers).
In reality, Thomas was deeply disturbed by the spread of Averroism and was angered when he discovered Siger of Brabant teaching Averroistic interpretations of Aristotle to Parisian students. On 10 December 1270, the Bishop of Paris, Etienne Tempier, issued an edict condemning thirteen Aristotelian and Averroistic propositions as heretical and excommunicating anyone who continued to support them. Many in the ecclesiastical community, the so-called Augustinians, were fearful that this introduction of Aristotelianism and the more extreme Averroism might somehow contaminate the purity of the Christian faith. In what appears to be an attempt to counteract the growing fear of Aristotelian thought, Thomas conducted a series of disputations between 1270 and 1272: De virtutibus in communi (On Virtues in General), De virtutibus cardinalibus (On Cardinal Virtues), De spe (On Hope).
Final days and “straw” (1272–1274)
In 1272 Thomas took leave from the University of Paris when the Dominicans from his home province called upon him to establish a studium generale 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. He took his time at Naples to work on the third part of the Summawhile giving lectures on various religious topics. He also preached to the people of Naples every day in Lent, 1273. These sermons on the commandments, the creed, the Our Father and Hail Mary were very popular.
On one occasion, at 1273 at the Dominican convent of Naples in the chapel of Saint Nicholas, after Matins, Thomas lingered and was seen by the sacristan Domenic of Caserta to be levitating in prayer with tears before an icon of the crucified Christ. Christ said to Thomas, “You have written well of me, Thomas. What reward would you have for your labor?” Thomas responded, “Nothing but you, Lord.” After this exchange something happened, but Thomas never spoke of it or wrote it down.
On 6 December 1273, another mystical experience took place. While he was celebrating Mass, he experienced an unusually long ecstasy. Because of what he saw, he abandoned his routine and refused to dictate to his socius Reginald of Piperno. When Reginald begged him to get back to work, Thomas replied: “Reginald, I cannot, because all that I have written seems like straw to me” (mihi videtur ut palea). As a result, the Summa Theologica would remain uncompleted. What exactly triggered Thomas’ change in behavior is believed by Catholics to have been some kind of supernatural experience of GOD. After taking to his bed, he did recover some strength.
In 1054 the Great Schism had occurred between the Latin Church following the Pope (known as the Catholic Church) in the West, and the Patriarchate of Constantinople in the East (known as the Eastern Orthodox Church). Looking to find a way to reunite the Eastern Orthodox Church and the Catholic Church, Pope Gregory X convened the Second Council of Lyon to be held on 1 May 1274 and summoned Thomas to attend. At the meeting, Thomas’ work for Pope Urban IV concerning the Greeks, Contra errores graecorum, was to be presented.
On his way to the Council, riding on a donkey along the Appian Way, he struck his head on the branch of a fallen tree and became seriously ill again. He was then quickly escorted to Montecassino to convalesce. After resting for a while, he set out again, but stopped at the Cistercian Fossanova Abbey after again falling ill. The monks nursed him for several days, and as he received his last rites he prayed: “I receive Thee, ransom of my soul. For love of Thee have I studied and kept vigil, toiled, preached and taught….” He died on 7 March 1274 while giving commentary on the Song of Songs.
Thomas was a theologian and a Scholastic philosopher. However, he never considered himself a philosopher, and criticized philosophers, whom he saw as pagans, for always “falling short of the true and proper wisdom to be found in Christian revelation.” With this in mind, Thomas did have respect for Aristotle, so much so that in the Summa, he often cites Aristotle simply as “the Philosopher.” Much of his work bears upon philosophical topics, and in this sense may be characterized as philosophical. Thomas’ philosophical thought has exerted enormous influence on subsequent Christian theology, especially that of the Catholic Church, extending to Western philosophy in general. Thomas stands as a vehicle and modifier of Aristotelianism and Neoplatonism. In fact, Thomas modified both Aristotelianism and Neoplatonism by way of heavy reliance on the Pseudo-Dionysius. This source has arguably been assessed not as a communicator of tradition, but as a polemicist, who tried to alter Neo-Platonic tradition in a novel way for the Christian world that would make notions of complicated Divine Hierarchies more of an emphasis than notions of direct relationship with the figure of Christ as Mediator. Indeed, a number of Catholic sources contend that Thomas was influenced more by this concoction than any other source, including Aristotle.
Commentaries on Aristotle
Thomas wrote several important commentaries on Aristotle’s works, including On the Soul, Nicomachean Ethics and Metaphysics. His work is associated with William of Moerbeke’s translations of Aristotle from Greek into Latin.
Thomas believed “that for the knowledge of any truth whatsoever man needs divine help, that the intellect may be moved by GOD to its act.” However, he believed that human beings have the natural capacity to know many things without special divine revelation, even though such revelation occurs from time to time, “especially in regard to such (truths) as pertain to faith.” But this is the light that is given to man by GOD according to man’s nature: “Now every form bestowed on created things by GOD has power for a determined act[uality], which it can bring about in proportion to its own proper endowment; and beyond which it is powerless, except by a superadded form, as water can only heat when heated by the fire. And thus the human understanding has a form, viz. intelligible light, which of itself is sufficient for knowing certain intelligible things, viz. those we can come to know through the senses.”
Thomas’ ethics are based on the concept of “first principles of action.” In his Summa theologiae, he wrote:
Virtue denotes a certain perfection of a power. Now a thing’s perfection is considered chiefly in regard to its end. But the end of power is act. Wherefore power is said to be perfect, according as it is determinate to its act.
Aquinas emphasized that “Synderesis is said to be the law of our mind, because it is a habit containing the precepts of the natural law, which are the first principles of human actions.”
According to Aquinas “…all acts of virtue are prescribed by the natural law: since each one’s reason naturally dictates to him to act virtuously. But if we speak of virtuous acts, considered in themselves, i.e., in their proper species, thus not all virtuous acts are prescribed by the natural law: for many things are done virtuously, to which nature does not incline at first; but that, through the inquiry of reason, have been found by men to be conductive to well living.” Therefore, we must determine if we are speaking of virtuous acts as under the aspect of virtuous or as an act in its species.
Thomas defined the four cardinal virtues as prudence, temperance, justice, and fortitude. The cardinal virtues are natural and revealed in nature, and they are binding on everyone. There are, however, three theological virtues: faith, hope, and charity. Aquinas also describes the virtues as imperfect (incomplete) and perfect (complete) virtues. A perfect virtue is any virtue with charity, charity completes a cardinal virtue. A non-Christian can display courage, but it would be courage with temperance. A Christian would display courage with charity. These are somewhat supernatural and are distinct from other virtues in their object, namely, GOD:
Now the object of the theological virtues is GOD Himself, Who is the last end of all, as surpassing the knowledge of our reason. On the other hand, the object of the intellectual and moral virtues is something comprehensible to human reason. Wherefore the theological virtues are specifically distinct from the moral and intellectual virtues.
Thomas Aquinas wrote “Greed is a sin against GOD, just as all mortal sins, in as much as man condemns things eternal for the sake of temporal things.”
Furthermore, Thomas distinguished four kinds of law: eternal, natural, human, and divine. Eternal law is the decree of GOD that governs all creation. It is, “That Law which is the Supreme Reason cannot be understood to be otherwise than unchangeable and eternal.” Natural law is the human “participation” in the eternal law and is discovered by reason. Natural law is based on “first principles”:
. . . this is the first precept of the law, that good is to be done and promoted, and evil is to be avoided. All other precepts of the natural law are based on this . . .
Whether the natural law contains several precepts, or one only is explained by Aquinas, “All the inclinations of any parts whatsoever of human nature, e.g., of the concupiscible and irascible parts, in so far as they are ruled by reason, belong to the natural law, and are reduced to one first precept, as stated above: so that the precepts of the natural law are many in themselves, but are based on one common foundation.”
The desires to live and to procreate are counted by Thomas among those basic (natural) human values on which all human values are based. According to Thomas, all human tendencies are geared towards real human goods. In this case, the human nature in question is marriage, the total gift of oneself to another that ensures a family for children and a future for mankind. To clarify for Christian believers, Thomas defined love as “to will the good of another.”
Concerning the Human Law, Aquinas concludes, “…that just as, in the speculative reason, from naturally known indemonstrable principles, we draw the conclusions of the various sciences, the knowledge of which is not imparted to us by nature, but acquired by the efforts of reason, so to it is from the precepts of the natural law, as from general and indemonstrable principles, that human reason needs to proceed to the more particular determination of certain matters. These particular determinations, devised by human reason, are called human laws, provided the other essential conditions of law be observed….” Human law is positive law: the natural law applied by governments to societies.
Natural and human law is not adequate alone. The need for human behavior to be directed made it necessary to have Divine law. Divine law is the specially revealed law in the scriptures. Aquinas quotes, “The Apostle says (Hebrews 7.12): The priesthood being translated, it is necessary that a translation also be made of the law. But the priesthood is twofold, as stated in the same passage, viz, the levitical priesthood, and the priesthood of Christ. Therefore the Divine law is twofold, namely, the Old Law and the New Law.”
Thomas also greatly influenced Catholic understandings of mortal and venial sins.
Thomas Aquinas, refers to animals as dumb and that the natural order has declared animals for man’s use. Thomas denied that human beings have any duty of charity to animals because they are not persons. Otherwise, it would be unlawful to use them for food. But this does not give humans the license to be cruel to them, for “cruel habits might carry over into our treatment of human beings.”
Thomas contributed to economic thought as an aspect of ethics and justice. He dealt with the concept of a just price, normally its market price or a regulated price sufficient to cover seller costs of production. He argued it was immoral for sellers to raise their prices simply because buyers were in pressing need for a product.
Aquinas’ theory of political order became highly influential. He sees man as a social being that lives in a community and interacts with its other members. That leads, among other things, to the division of labour.
Thomas thinks that monarchy is the best form of government, because a monarch does not have to form compromises with other persons. Moreover, according to Thomas, oligarchy degenerates more easily into tyranny than monarchy. To prevent a king from becoming a tyrant, his political powers must be curbed. Unless an agreement of all persons involved can be reached, a tyrant must be tolerated, as otherwise the political situation could deteriorate into anarchy, which would be even worse than tyranny.
The kings are GOD’s representatives in their territories. But the church, represented by the popes, is above the kings in matters of doctrine and morality. As a consequence, the kings and other worldly rulers are obliged to adapt their laws to the Catholic church’s doctrines and ethics. For example, the worldly authorities have to execute persons whom the church has sentenced to death for heresy and they have to fight and subdue groups of heretics such as the Albigenses and Waldensians to restore the unity of the church.
Following Aristotle’s concept of slavery, Thomas justifies this institution on the grounds of natural law.