METAPHYSICS OF THOMAS AQUINAS. A CRITICAL RE-EVALUATION

The project “The Metaphysics of Thomas Aquinas: A Critical Re-Evaluation” is founded on the conviction that the time has come for a concerted effort—by many hands, by philosophers of many schools—to re-evaluate philosophical system of St Thomas Aquinas.

I share this conviction—I share it despite the fact that I am very far from being a Thomist. In the sequel, I will say something about why I reject Thomism, and shall then go on to say why it is that I enthusiastically support the proposed critical evaluation despite my rejection of Thomism.

At the most fundamental level, I am not a Thomist because that I am a Platonist. (At any rate a Platonist of a sort.) Because I am a Platonist, I reject many of the most fundamental postulates of the Aristotelians—and, apart perhaps from Aristotle himself, no philosopher is more of an Aristotelian than Thomas.

If I were to single out one particular aspect of Aristotelianism to be my point of fundamental disagreement with that philosophy, I would say that it was the distinction between the two relations that things in other categories than (primary) substance can bear to substances: they may be “said of” substances or they may “inhere in” substances. I reject the second. As a Platonist, I say: there are things that can be said of things (that is, there are attributes and relations), and there are things that cannot be said of things (substances). And there is nothing else. That is, there are no accidents, no things whose mode of being is to “inhere in” substances. (Nor are there things in other categories than “accident” that inhere in substances.)

The Platonism to which I adhere recognizes only two categories. Alternative names for each of these categories are listed in each of the two following columns; the names in each column have the same referents, although I do not contend that, e.g., ‘substance’ and ‘concrete object’ or ‘universal’ and ‘relation’ mean the same thing.

The objects that fall under the terms in the right-hand column are without spatial and temporal characteristics, necessarily existent, and incapable of entering into causal relations (and hence uncreated).

One interesting example of the consequences of my view has come to light in discussions of the metaphysics of the Eucharist with my Roman Catholic colleagues. They sometimes ask me, “Do you believe in transubstantiation?” I ask them to define ‘transubstantiation’. They reply, “Well, as Aquinas defines it.” And I can say only, “I’m sorry—I don’t understand even what he says about the unconsecrated bread.”

I say this because, according to Thomas, there inhere in the bread “the accidents of bread”—and these remain when the priest says “Hoc est corpus meum” and there is no longer bread on the paten. We in the congregation, when we look at the paten, see precisely what we saw before the words of consecration were pronounced: the accidents of bread. The role that accidents play in Thomas’s “Aristotelian Eucharist” is nicely brought out by contrasting it with a metaphysic of the Eucharist proposed by Descartes—a metaphysic in which “accidents” play no role. Descartes’s proposal was that, when the Words of Consecration are spoken, the bread and wine are annihilated and the flesh and blood of Christ are miraculously present on the paten and in the chalice; but our human sensory apparatus does not “register” this substantial chance because God creates within the minds of those present “sense data” of bread-on-the-paten and wine-in-thecup. This proposal was vehemently rejected by the Church on the ground that it violated the principle—a cornerstone of Descartes’s own philosophy—that God is not a deceiver, not a purveyor of optical illusion. Obviously, the adherents of the Aristotelian metaphysic of the Eucharist argued, if what was present to the senses before the consecration—that is, the accidents of bread and wine; for substance is only ever present to our human senses vicariously, only through our sensory awareness of the accidents that inhere in it—continues to be present to the senses after the consecration, then our post-consecration sensory representation of what is present on the paten and in the chalice is not an illusion.

Although I am no friend of the Cartesian Eucharistic theology, neither can I accept its Aristotelian rival. I cannot accept it because I simply have no idea, no idea whatever, what the words ‘the accidents of bread’ mean. But I am sure of one thing: if the phrase means anything at all, then the existence of “the accidents of bread” is incompatible with Platonism.

I remember once having had a pleasant discussion on various metaphysical topics with a Czech priest at a conference in Prague—a Dominican he must have been from his habit, a member of the same religious order as Thomas. It was, I say, a pleasant dispute, but my Dominican friend was becoming more and more impatient with my refusal to grant him what seemed to him to have been the most obvious of premises. Finally, I said to him, “I think I see the problem: you have never before encountered a Platonist, a living Platonist standing right before you. You have met Platonism only in books. Your teachers and every philosopher you have ever talked to have been Aristotelians.”

And I remember a second conversation with an Aristotelian, a Notre Dame graduate student who was an ardent Thomist. As the conversation progressed, I became as exasperated with what this young man was saying to me as the Czech Dominican had been with what I had said to him. I was exasperated because it seemed to me that he was populating the world with all sorts of imaginary particulars. (We Platonists are often accused of populating the world with all manner of invented universals; I accuse Aristotelians of populating the world with all manner of invented particulars.) My exasperation came to the point at which I thought I’d illustrate the absurdity of his ontology with a telling example. I placed two coins on the table and moved them toward each other till they touched. I asked him, “Did a certain particular thing come into existence at the moment the two coins touched—a thing called ‘the contact of the two coins’?” “Of course,” he replied.

What I have said is hardly the beginning of a statement of my difficulties with the metaphysics of Aristotle—and, therefore, with the metaphysics of Thomas.

I should say, however, that the word ‘metaphysics’ in the phrase “The Metaphysics of Thomas Aquinas: A Critical Re-Evaluation” seems to have its modern or post-Medieval meaning, a meaning that places under the heading “metaphysics” many topics that Thomas would not have regarded as belonging to metaphysica or Aristotle to prote philosophia. (I base this judgment on the “topics” listed in the document called Annex 2.) For example, “form and matter” would, before the seventeenth century, have been said to belong primarily to “physics” (although—I concede—there is an important discussion of this topic in Metaphysics Z). The medieval philosophers, moreover, would have said that their interminable disputes about nominalism and realism belonged to “logic” (which included what we’d call philosophical semantics today) and not to “metaphysics.” Although I reject almost everything Aquinas has to say on the topics he would have said belonged to metaphysica, I find much to agree with in his metaphysics in the broader, present-day sense of ‘metaphysics’.

If I may borrow a useful transitional device of Herodotus: let this suffice for a statement of my reasons for rejecting Thomism.

I now turn to my reasons for enthusiastically endorsing the project “The Metaphysics of Thomas Aquinas: A Critical Re-Evaluation.” There are three.

(a) Thomas is one of the greatest and most important of philosophers and theologians. (I am a staunch advocate of the thesis that theology—at any rate, much of theology—is blind without philosophy. A thesis that, in my view, the history of theology during the last two centuries amply demonstrates.)

(b) Thomas is one of the Doctors of the Church. (And, one might almost say, since Æterni Patris, the Doctor of the Church.) Well, the Roman Church—but I, although I am an Anglican, I nevertheless regard the Roman Church as the central pillar of Christianity. I believe that that all Christians must take any judgment of the Roman Church very seriously: if they disagree with it, it must be only after lengthy and careful reflection—reflection that must begin with an attempt to achieve absolute certainty that they understand it.

(c) It is important for a philosopher who rejects a system of philosophy—and particularly important if that system of philosophy is of great historical importance and is still accepted by many very able philosophers—to be sure that he or she has encountered the best version of or presentation of that system, and has listened to the best defenses of that system against the criticisms that are commonly brought against it. I reject the Thomistic system—for reasons that I have given—but I am virtually certain that I have not seen it presented as well as it might have been. And I am virtually certain that the arguments I would bring against it could be met with counter-arguments that are far better than any I have actually heard. The Project would almost certainly lead to a presentation of Thomism that I should find harder to dismiss than the presentations I have encountered.

_{1. I call this document a letter because I do not know what else to call it. Perhaps Heidegger’s title, “Brief Über den Humanismus” demonstrates that, as a literary term, ‘letter’ has a broad enough meaning that it may properly be applied to the present document.} 

Chapel Hill
10 August 2020

Peter van Inwagen
_{John Cardinal O’Hara Professor of Philosophy emeritus, the University of Notre Dame
Research Professor of Philosophy, Duke University
Honorary President, the International Society for Formal Ontology}