Thomas Aquinas: Revolutionary and Saint

Thomas Aquinas (1225–1274) is one of the two most famous Catholic theologians and philosophers; the other is Augustine (354–430). Seven hundred years ago, on 18 July 1323, Pope John XXII presided at Aquinas’s canonization as a saint. In 1567, Pope Pius V proclaimed Aquinas to be a “Doctor of the Church,” one whose teachings occupy a special place in Catholic theology. Thomas was the first thinker after the time of the Church Fathers to be so honored. In 1879 Pope Leo XIII issued a famous encyclical, Aeterni Patris: On the Restoration of Christian Philosophy, calling on all Catholic educational institutions to give pride of place to the theology and philosophy of Thomas Aquinas. Although today he is a well-established authority in both philosophy and theology, in his own time he was considered a revolutionary thinker whose views challenged the accepted intellectual establishment of the West.

As a young man in Italy, Thomas joined the recently founded Dominican Order. Along with the Franciscans, the Dominicans were part of a widespread reform movement within the Catholic Church. In many ways these new religious orders were urban-based youth movements and, to be effective in their apostolate of reform in the Church, the Dominicans sought out the ablest young men and quickly established houses of study in the great university centers, such as Bologna, Paris, and Oxford.

Thomas traveled north to Paris (1245) to study with Albert the Great at the University of Paris. Albert was already well known for his work in philosophy, theology, and the natural sciences. Like other Dominicans of his time, Thomas walked to Paris from Italy; and then, with Albert, he walked to Cologne (1248) where the Dominicans were establishing another center of studies. He came back to Paris (in 1252) to complete his studies to become a Master of Theology. After three years in Paris, he spent the next ten years in various places in Italy, only to return to Paris in the late 1260s. There, he once again occupied a chair as Master of Theology and confronted various intellectual and institutional challenges, especially concerning the proper relationship between philosophy and theology.

 

Aristotelian Revolution

Universities in the thirteenth century were relatively new institutions—centers of lively intellectual life. In addition to a liberal arts faculty, the universities had advanced faculties of law, medicine, and theology. Paris was especially famous for its faculty of theology. Thomas was a member of a brand-new religious order, and his professional life was often connected with this new institution in the West, the university. The growing intellectual authority, and relative institutional autonomy, of the new universities often represented a challenge to the established order, both religious and secular.

Thomas lived at a critical juncture in the history of Western culture. The vast intellectual revolution in which he participated was the result of the translation into Latin of almost all the works of Aristotle. Aristotle offered, so it seemed, a comprehensive understanding of man, of the world, and even of God. In the Divine Comedy, Dante’s Virgil calls Aristotle “the master of those who know.”

Aristotle’s works came to the Latin West in the late twelfth century and first half of the thirteenth century, with a set of very compelling, and often conflicting, interpretations from Muslim and Jewish sources: thinkers such as Avicenna, Averroës, and Maimonides. How should Christian theologians react to this new way of understanding things? Aristotle’s claims about the eternity of the world, the mortality of the human soul, and how to understand happiness seemed to represent a fundamental challenge to Christian revelation. Should the teaching of Aristotle be rejected, or at least restricted? Many Christian thinkers in the thirteenth century thought so, and there were various attempts—mostly unsuccessful—throughout the century to ban Aristotle from the curriculum of the new universities. The most famous were lists of condemned propositions in 1270 and 1277, issued by the Bishop of Paris, Étienne Tempier.

Thomas, following his teacher Albert, was among the first to see, and to see profoundly, the value for Christian theology that Aristotle’s scientific and philosophical revolution offered. Thomas was first of all a theologian, committed to setting forth clearly the fundamentals of the Christian faith. But, precisely because he was a theologian, he recognized that he had to be a philosopher and have scientific knowledge as well. His most famous theological work, the Summa Theologiae, contains many philosophical arguments that have their own formal independence and validity, yet are organized in the service of Christian truth. Thomas recognized that whatever truths science and philosophy disclose cannot, in the final analysis, be a threat to truths divinely revealed by God: after all, God is the author of all truth—the truths of both reason and faith. Thomas thought that by reason alone it was possible to demonstrate not only that there is a God but that this God is the creator of all that is. He argued that faith perfects and completes what reason can tell us about the Creator and all creatures.

 

As an astute student of Aristotle, Thomas was critical not only of those who ignored Aristotle, but also of those who, sometimes in the tradition of Averroës, read Aristotle in a way that did indeed result in contradictions of Christian belief. Thomas’s philosophical position was not mainstream in his own day; rather, his more traditional colleagues’ views were more widely accepted. Nowhere was this difference more apparent than in debates about the proper relationship between philosophy and theology on a wide variety of questions about human nature and the doctrine of creation. Those opposed to Thomas came from what can broadly be called an Augustinian tradition, which resolutely insisted that philosophy must always teach what faith affirms. Thomas did reject the kind of excessive philosophical autonomy found in Averroës, but he also rejected the tendency toward fideism found in his more traditionalist opponents.

Thomas wrote extensive commentaries on major Aristotelian treatises, such as the Physics, the De Anima (On the Soul), the Posterior Analytics, the Metaphysics, and the Nicomachean Ethics, in which he sought to present comprehensive views of these subjects. One can see Thomas employing principles drawn from Aristotle, as well as from other sources in Greek philosophy, in his wide-ranging collections of disputed questions On Truth and On the Power of God, in Summa contra Gentiles, and even in his biblical commentaries.

Creation and Causality

Throughout his writings, Thomas is keen to emphasize the importance of thinking analogically: recognizing, for example, that to speak of God as cause and of creatures as causes requires that the term “cause” be predicated of both God and creatures in a way that is both similar and different. For Thomas, an omnipotent God, complete cause of all that is, does not challenge the existence of real causes in nature, causes that, for example, the natural sciences disclose. God’s power is so great that He causes all created causes to be the causes that they are.

One of his greatest insights concerns a proper understanding of God’s act of creating and its relationship to science. The natural sciences explain changes in the world; creation, on the other hand, is a metaphysical and theological account of the very existence of things, not of changes in things. Such a distinction remains useful for discussions in our own day about the philosophical and theological implications of evolutionary biology and cosmology. The subject of these disciplines is change, indeed change on a grand scale. But as Thomas would remind us, creation is not a change, since any change requires something that changes. Rather, creation is a metaphysical relationship of dependence. Creation out of nothing does not mean that God changes “nothing” into something. Any creature separated from God’s causality would be nothing at all. Creation is not primarily some distant event; it is the ongoing causing of the existence of whatever is.

In one of the more radical sentences written in the thirteenth century, Thomas claimed that “not only does faith hold that there is creation, but reason also demonstrates creation.” Here he is distinguishing between a philosophical and a theological analysis of creation. Arguments in reason for the world’s being created occur in the discipline of metaphysics: from the distinction between what it means for something to be (its essence) and its existence. This distinction ultimately leads to the affirmation that all existence necessarily has a cause.

The philosophical sense of creation concerns the fundamental dependence of any creature’s being on the constant causality of the Creator. For Thomas, an eternal universe would be just as much a created universe as a universe with a temporal beginning. From the time of the Church Fathers, theologians always contrasted an eternal universe with a created one. Thomas did believe that the universe had a temporal beginning, but he thought that such knowledge was exclusively a matter of divine revelation, as disclosed in the opening of Genesis and dogmatically affirmed by the Fourth Lateran Council (1215).

The theological sense of creation incorporates the philosophical sense. Thomas viewed creation as much more than what reason alone discovers. With faith, he sees all of reality coming from God as a manifestation of God’s goodness and ordered to God as its end. This relationship is a grand panorama of out-flow and return, analogous to the dynamic life of the Persons of the Trinity.

 

As the German philosopher and historian Joseph Pieper observed, the doctrine of creation is the key to almost all of Thomas’s thought. The revolutionary nature of Thomas’s position on creation is evident in the way it differs from that of his teacher, Albert the Great, and his colleague at the University of Paris, Bonaventure. Both thought that the fact of creation could only be known by faith and that a created world necessarily meant a world with a temporal beginning. Neither fully appreciated Thomas’s observation that creation is not a change. In fact, one of the condemnations of 1277 by the Bishop of Paris noted that it was an error to hold that creation is not a change.

It may be difficult for us to appreciate the radical nature of Thomas’s thought, especially his brilliant synthesis of faith and reason that honored the appropriate autonomy of each. Thomas does not fit easily into a philosophical or a theological category. He thought that human beings could come to knowledge of the world and of God, but he also recognized that a creature’s knowledge of the Creator must always fall short of what and who the Creator is.

For Thomas, reason—deployed in all the intellectual disciplines (including philosophy and the natural sciences)—is a necessary complement to religious faith. After all, a believer is a human being: a rational animal. Faith perfects but does not abolish what reason discloses. In deploying his understanding of the relationship between reason and faith, Thomas offered what were for his time radically novel views about nature, human nature, and God. What commends these views to us—and what was later realized by the Catholic Church—is not their novelty but their truth. Ironically, in the context of today’s intellectual currents that reject metaphysics and embrace various forms of materialism, Thomas’s thought is once again a radical, if not revolutionary, enterprise.

Eppur si muove: The Legend of Galileo

There are few images of the modern world more powerful than that of the humbled Galileo, kneeling before the cardinals of the Holy Roman and Universal Inquisition, being forced to admit that the Earth did not move. The story is familiar: that Galileo represents science fighting to free itself from the clutches of blind faith, biblical literalism, and superstition. The story has fascinated generations, from the philosophes of the Enlightenment to scholars and politicians in the nineteenth and twentieth centuries.

The specter of the Catholic Church’s condemnation of Galileo continues to influence the modern world’s understanding of the relationship between religion and science. In October 1992, Pope John Paul II appeared before the Pontifical Academy of the Sciences to accept formally the findings of a commission tasked with historical, scientific, and theological inquiry into the Inquisition’s treatment of Galileo. The Pope noted that the theologians of the Inquisition who condemned Galileo failed to distinguish properly between particular biblical interpretations and questions pertaining to scientific investigation.

The Pope also observed that one of the unfortunate consequences of Galileo’s condemnation was that it has been used to reinforce the myth of an incompatibility between faith and science. That such a myth is alive and well was immediately apparent in the way the American press described the event in the Vatican. The headline on the front page of The New York Times was representative: “After 350 Years, Vatican Says Galileo Was Right: It Moves.” Other newspapers, as well as radio and television networks, repeated essentially the same claim.

The New York Times story is an excellent example of the persistence and power of the myths surrounding the Galileo affair. The newspaper claimed that the Pope’s address would “rectify one of the Church’s most infamous wrongs—the persecution of the Italian astronomer and physicist for proving the Earth moves about the Sun.” For some, the story of Galileo serves as evidence for the view that the Church has been hostile to science, and the view that the Church once taught what it now denies, namely, that the Earth does not move. Some take it as evidence that teachings of the Church on matters of sexual morality or of women’s ordination to the priesthood are, in principle, changeable. The “reformability” of such teachings is, thus, the real lesson of the “Galileo Affair.”

But modern treatments of the affair not only miss key context surrounding the Inquisition’s condemnation of Galileo; they also misinterpret what the Catholic Church has always taught about faith, science, and their fundamental complementarity.

 

Galileo and the Inquisition in the Seventeenth Century

Galileo’s telescopic observations convinced him that Copernicus was correct. In 1610, Galileo’s first astronomical treatise, The Starry Messenger, reported his discoveries that the Milky Way consists of innumerable stars, that the moon has mountains, and that Jupiter has four satellites. Subsequently, he discovered the phases of Venus and spots on the surface of the sun. He named the moons of Jupiter the “Medicean Stars” and was rewarded by Cosimo de’ Medici, Grand Duke of Tuscany, with appointment as chief mathematician and philosopher at the Duke’s court in Florence. Galileo relied on these telescopic discoveries, and arguments derived from them, to bolster public defense of Copernicus’s thesis that the Earth and the other planets revolve about the sun.

When we speak of Galileo’s defense of the thesis that the Earth moves, we must be especially careful to distinguish between arguments in favor of a position and arguments that prove a position to be true. Despite the claims of The New York Times, Galileo did not prove that the Earth moves about the sun. In fact, Galileo and the theologians of the Inquisition alike accepted the prevailing Aristotelian ideal of scientific demonstration, which required that science be sure and certain knowledge, different in some ways from what we today accept as scientific. Furthermore, to refute the geocentric astronomy of Ptolemy and Aristotle is not the same as to demonstrate that the Earth moves. Danish astronomer Tycho Brahe (1546–1601), for example, had created another account of the heavens. He argued that all the planets revolved about the sun, which itself revolved about a stationary Earth. In fact, Galileo himself did not think that his astronomical observations provided sufficient evidence to prove that the Earth moves, although he did think that they called Ptolemaic geocentric astronomy into question. Galileo hoped eventually to argue from the fact of ocean tides to the double motion of the Earth as the only possible cause, but he did not succeed.

 

Cardinal Robert Bellarmine, Jesuit theologian and member of the Inquisition, told Galileo in 1615 that if there were a true demonstration for the motion of the Earth, then the Church would have to abandon its traditional reading of those passages in the Bible that appeared to be contrary. But in the absence of such a demonstration (and especially in the midst of the controversies of the Protestant Reformation), the Cardinal urged prudence: treat Copernican astronomy simply as a hypothetical model that accounts for the observed phenomena. It was not Church doctrine that the Earth did not move. If the Cardinal had thought that the immobility of the Earth were a matter of faith, he could not argue, as he did, that it might be possible to demonstrate that the Earth does move.

The theologians of the Inquisition and Galileo adhered to the ancient Catholic principle that, since God is the author of all truth, the truths of science and the truths of revelation cannot contradict one another. In 1616, when the Inquisition ordered Galileo not to hold or to defend Copernican astronomy, there was no demonstration for the motion of the Earth. Galileo expected that there would be such a demonstration; the theologians did not. It seemed obvious to the theologians in Rome that the Earth did not move and, since the Bible does not contradict the truths of nature, the theologians concluded that the Bible also affirms that the Earth does not move. The Inquisition was concerned that the new astronomy seemed to threaten the truth of Scripture and the authority of the Catholic Church to be its authentic interpreter.

The Inquisition did not think that it was requiring Galileo to choose between faith and science. Nor, in the absence of scientific knowledge for the motion of the Earth, would Galileo have thought that he was being asked to make such a choice. Again, both Galileo and the Inquisition thought that science was absolutely certain knowledge, guaranteed by rigorous demonstrations. Being convinced that the Earth moves is different from knowing that it moves.

The disciplinary decree of the Inquisition was unwise and imprudent. But the Inquisition was subordinating scriptural interpretation to a scientific theory, geocentric cosmology, that would eventually be rejected. Subjecting scriptural interpretation to scientific theory is just the opposite of the subjection of science to religious faith!

In 1632, Galileo published his Dialogue Concerning the Two Chief World Systems, in which he supported the Copernican “world system.” As a result, Galileo was charged with disobeying the 1616 injunction not to defend Copernican astronomy. The Inquisition’s injunction, however ill‑advised, only makes sense if we recognize that the Inquisition saw no possibility of a conflict between science and religion, both properly understood. Thus, in 1633, the Inquisition, to ensure Galileo’s obedience, required that he publicly and formally affirm that the Earth does not move. Galileo, however reluctantly, acquiesced.

From beginning to end, the Inquisition’s actions were disciplinary, not dogmatic, although they were based on the erroneous notion that it was heretical to claim that the Earth moves. Erroneous notions remain only notions; opinions of theologians are not the same as Christian doctrine. The error the Church made in dealing with Galileo was an error in judgment. The Inquisition was wrong to discipline Galileo, but discipline is not dogma.

 

The Development of the Legend of Galileo

The mythic view of the Galileo affair as a central chapter in the warfare between science and religion became prominent during debates in the late nineteenth century over Darwin’s theory of evolution. In the United States, Andrew Dickson White’s History of the Warfare of Science with Theology in Christendom (1896) enshrined what has become a historical orthodoxy difficult to dislodge. White used Galileo’s “persecution” as an ideological tool in his attack on the religious opponents of evolution. Since it was so obvious by the late nineteenth century that Galileo was right, it was useful to see him as the great champion of science against the forces of dogmatic religion. The supporters of evolution were seen as nineteenth-century Galileos; the opponents of evolution were seen as modern inquisitors. The Galileo affair was also used to oppose claims about papal infallibility, formally affirmed by the First Vatican Council in 1870. As White observed: had not two popes (Paul V in 1616 and Urban VIII in 1633) officially declared that the Earth does not move?

The persistence of the legend of Galileo, and of the image of “warfare” between science and religion, has played a central role in the modern world’s understanding of what it means to be modern. Even today the legend of Galileo serves as an ideological weapon in debates about the relationship between science and religion. It is precisely because the legend has been such an effective weapon that it has persisted.

 

For example, a discussion in bioethics from several years ago drew on the myths of the Galileo affair. In March 1987, when the Catholic Church published condemnations of in vitro fertilization, surrogate motherhood, and fetal experimentation, there appeared a page of cartoons in one of Rome’s major newspapers, La Repubblica, with the headline: ‘In Vitro Veritas.’ In one of the cartoons, two bishops are standing next to a telescope, and in the distant night sky, in addition to Saturn and the Moon, there are dozens of test-tubes. One bishop turns to the other, who is in front of the telescope, and asks: “This time what should we do? Should we look or not?” The historical reference to Galileo was clear.

In fact, at a press conference at the Vatican, then-Cardinal Joseph Ratzinger was asked whether he thought the Church’s response to the new biology would not result in another “Galileo affair.” The Cardinal smiled, perhaps realizing the persistent power—at least in the popular imagination—of the story of Galileo’s encounter with the Inquisition more than 350 years before. The Vatican office that Cardinal Ratzinger was then the head of, the Congregation for the Doctrine of the Faith, is the direct successor to the Holy Roman and Universal Inquisition into Heretical Depravity.

There is no evidence that in 1633 when Galileo acceded to the Inquisition’s demand that he formally renounce the view that the Earth moves, he muttered under his breath, eppur si muove, “but still it moves.” What continues to move, despite evidence to the contrary, is the legend that Galileo represents reason and science in conflict with faith and religion. Galileo and the Inquisition shared common first principles about the nature of scientific truth and the complementarity between science and religion. In the absence of scientific knowledge, at least as understood by both the Inquisition and Galileo, that the Earth moves, Galileo was required to affirm that it did not. However unwise it was to insist on such a requirement, the Inquisition did not ask Galileo to choose between science and faith.