Few religious figures allow their sacred texts to be reconciled with others from different traditions. Even if the latter were religious texts, being associated with another religion or sect is enough reason to disregard them. Nevertheless, it is difficult to think about contemporary questions like “reconciling religion/faith with science/reason” or openness to the other, without delving deeply into the works of the Dominican monk Thomas Aquinas. He was one among the world’s most famous builders of bridges linking divergent traditions, and those who have studied his most prominent works, “Summa Theologica” (“Summary of Theology) and “Liber De Veritate Catholicae Fidei Contra Errores Infidelium” (Book on the Truth of the Catholic Faith against the Errors of the Unbelievers) see him as having done more than anyone else to imbue Western Christian culture with ideas from elsewhere.
Aquinas builds on and develops the foundations laid by Saint Augustine, a theologian and philosopher of the fourth and fifth centuries who was profoundly influenced by Plato. Aquinas studied under Albertus Magnus (also known as Saint Albert the Great), the German Dominican monk who has been canonized a saint. Magnus was the one to introduce Averroes (Ibn Rushd) to Christian thinkers, and he was the first to combine Aristotle and Christianity.
Aquinas has been associated with an array of concepts. One is that every person, Christian or not, can discover the great truths through their mind, the most important of God’s gifts. In fact, non-Christians can be wise without knowing Christ, as virtuous ideas can come from everywhere, regardless of the religions and backgrounds of their advocates. Since his intellectual achievements gave thought a universal quality, they opened the minds and eyes of Christians to all other human beings from across the eras and continents and their reflections on the world.
Born to a noble Italian family in 1225, he taught in Paris and took an interest in the ancient texts of the Greeks and Romans, which had only recently been discovered at the time. And a century after his death, the Catholic Church canonized him a saint.
The fact is that during the late High Middle Ages (1200-1300), it became possible to make contributions that deviated slightly from the Orthodox tradition. Indeed, ecclesiastical circles felt that there was a need for a rejuvenation that could put an end to the Church’s intellectual stagnation and calcification. This engendered greater acceptance of the idea that worldly and divine knowledge could coexist, which eventually gave rise to new distinctions and classifications within the religious worldview. In fact, Dante (who died in 1321) placed pagan philosophers in the first circle of hell, meaning that while they would not ascend to heaven, they would not suffer like the other pagans.
However, these breakthroughs do not nullify the deeply entrenched difficulties. Aristotelian principles had been considered destructive pagan ideas by the Church, and they were forbidden up until 1277. The Archbishop of Paris condemned the teachings of Aristotle, Averroes, and Aquinas twice, once in 1270 and another in 1277. For his part, Dante placed Aquinas's spirit “in the sky of the sun” and claimed that he had been poisoned. It was only in the sixteenth century that a consensus emerged around Aquinas and his legacy, with his works becoming universally recognized as a component of Catholic belief. After that, in 1880, he was declared the patron saint of teachers and educational institutions because he had spent his life teaching.
Aquinas, whose philosophy is called “Scholasticism” and “Thomism,” is more indicative of the development of medieval Christian thought than any else. He also did more to link the Greco-Roman tradition with Christianity and reconcile classical teachings with paganism and Christian teachings. As for Aristotle, whom Aquinas called “the philosopher,” his writings had an unparalleled influence on him after having been brought to Europe by Muslims and Arabic translations. As is well known, Averroes' explanation and commentary on the Greek philosopher’s ideas remain among his most prominent intellectual contributions. Taking after Aristotle, Aquinas believed that nature was organized to serve beneficial and benign ends, and he also agreed that knowledge is not within us a-priori but attained through our senses and logical reasoning.
He borrowed ideas from other pagans as well, particularly Cicero, advocating his notion of natural laws as moral and normative laws that can be accessed through reason, regardless of any revelation. He also took great interest in Jewish and Muslim cultures, as represented by Maimonides and Averroes, who passed away two decades before his birth. Nonetheless, this did not prevent him from critiquing some of their ideas.
As for his starting point, it was that some of the world’s greatest thinkers and reformers are Pagans or non-Christians, meaning one can usefully discover the world through reason as well as faith. Some useful fields and activities, in economics, construction, and others, require only compliance with natural laws to navigate, with no need to refer to divine law. And there are evil acts, like children killing their parents, whose wickedness we do not need scripture to ascertain. On the other hand, if philosophy can prove the existence of God, it cannot prove the existence of the Christian Trinity, which is what theology sought to do. Though he puts forward “Five Ways” to demonstrate the existence of God, they are unfalsifiable claims that Aquinas formulates as logical arguments that can stand alone, without the need to reference theology and holy scripture. Nonetheless, some questions of reason can be answered by the knowledge presented by theology, and vice versa.
In general, Aquinas recognized the need for a division of labor, so to speak, through which non-religious spaces and ideas can emerge and evolve. Indeed, faith and reason are not the same, but they are not contradictory, as they have separate spheres and fields.
Aquinas’ ideas (which addressed countless issues) arose at a time when Islamic culture was struggling, with regard to reconciling reason and faith, with problems which resembled those that Christian culture had been struggling with. Averroes famously had his books burned and was persecuted and exiled, after Andalusia, Morocco, and Egypt had enjoyed a period of prosperity and openness. Thus, Aquinas wanted, among other things, to spare the Christian world of the pains that had been inflicted on the neighboring Islamic world.
And so, despite the robustness of his faith, he was largely successful in establishing a framework for free scientific research buttressed by openness to others and their ideas. Knowledge only becomes knowledge when it comes from several different sources: from revelation but also from science, from intuition but also from reason, and from monks but also from pagans and non-Christians. With this contribution, especially his coupling of Aristotle and Christianity, Aquinas took a great leap on the path to advancing rationality and crystallizing confidence in free and independent thought.
