Jacques Maritain Center: Thomistic Institute

From Augustine's Mind to Aquinas' Soul

John O'Callaghan
Creighton University

I. Introduction

In this paper I consider the institute topic of Aquinas' sources by examining a shift in Aquinas from an Augustinian philosophy of mind toward a more full blooded Aristotelian psychology. My method will be to argue against the philosophy of mind that Anthony Kenny attributes to Aquinas in his recent work Aquinas on Mind. Almost all of the reviews of Aquinas on Mind managed in the end to give it a qualified recommendation, this despite the fact that most of the reviewers found at least one serious and distinct difficulty with the work.(1) Still, none recognized the most fundamental problem with Kenny's account: there is no philosophy of mind in Aquinas, and in particular precisely where Kenny says it is to be found, in the first part of the Summa Theologiae in the questions often referred to as the "Treatise on Man." The main reason Aquinas has no philosophy of mind, is that Aquinas does not think there is a mind and for Aristotelian philosophical reasons that's a good thing too!

Kenny's Mind

In the long paper I have a lengthy discussion of Kenny's analysis. For reasons of time, I will only state here the crucial claims that he makes in order to understand the themes I develop in my account of Aquinas.

1) Philosophy of mind is an element of the "irreducible core amenable only to philosophy," along with epistemology, philosophy of language, metaphysics, and ethics, left over from the advance of modern science. We will always have it.

2) "Since the greatest medieval philosophers were theologians first and philosophers second, it is to their theological treatises rather than to their commentaries on De anima that one turns for their insights into philosophy of mind."(2)

3) Corollary: Aquinas was primarily a theologian, so his philosophy of mind is to be found in the Summa Theologiae in the "Treatise on Man."

4) Intellect is the capacity for acquiring linguistic and symbolic abilities.

5) 'Mind' and 'intellect' are not simply two words for the same thing.(p.42)

6) Will is the capacity for the pursuit of rational goals.

7) Mind is a "single indivisible capacity" "essentially consituted" from intellect and will.

8) Sensation is not a part of the mind, but is a contrast or foil against which to better understand the mind.

9) Mind for Aristotelians "sets us off" from other animals.

10) Kenny's reading of Aquinas in these respects is for all practical purposes identical to his own in The Metaphysics of Mind.

11) The difference is that Kenny does not want to allow for soul in his work, so he uses 'psyche' to refer to the sense powers, and 'mind' to refer to the indivisible power essentially constituted from intellect and will.

Absence of Mind in Aquinas

Aquinas has no such philosophy of mind, because for Aristotelian reasons he does not think that the term Kenny has analyzed successfully refers. The argument is divided into two parts. The first part looks at Aquinas' disputed question on mind in the De veritate. Here I grant that Aquinas holds a view roughly similar to the one Kenny attributes to him, but that it is Augustinian in form rather than Aristotelian. Once we recognize this early position, we are better prepared to recognize in the second part his decisive rejection of it in the Summa, under the influence of his commentary on Aristotle's De anima, the commentary that Kenny had advised we take no note of.

Augustine's De trintiate and the Early Thomistic Account of Mind

The most obvious Augustinian influence upon Aquinas in his early discussion of mind is Augustine's De trinitate, particularly in the last half of the work where Augustine turns from biblical exegesis toward a systematic examination of the Christian doctrine of the Holy Trinity. I can do no more than summarize Augustine's results as they bear on the De veritate. Augustine's goal is to find in creation the most adequate image of the Trinity of Father, Son, and Holy Spirit. In most of material creation one can find traces or signs, of God; nevertheless, it is only by turning away from sensible objects, inward toward his own conscious experience of himself as a spiritual, rational being that Augustine thinks he can find an adequate image of the Holy Trinity. He describes this movement as the transition from the outer man to the inner man. Success is guaranteed here because if the mind simply recalls itself to itself from its alienation; the mind "simply cannot not know itself;"(3) all it need do is remember. The image must be adequate to the doctrine Augustine holds by faith, namely that there is but one being, God, and three distinct Persons, who are yet each said to be the one being who is God. After trying out a number of possible images, each of which is found to be inadequate, he finds the adequate image in the mind remembering itself, knowing itself, and loving itself. So the key triad is identified as consisting of memory, intellect and will.

Augustine argues a number of theses about this trinity in the mind. First, "love and knowledge, [and presumably memory], are not in the mind as in a subject, but they too are substantially, just as the mind itself is; and even if they are posited relatively to each other, still each of them is its own substance."(p.273) Indeed, "the mind therefore and its love and knowledge are three somethings, and these three are one thing, and when they are complete they are equal."(4) Finally, "memory, understanding, and will, are not three lives but one life, nor three minds but one mind. So it follows of course that they are not three substances but one substance."(5) For Augustine, this is the inner man, that part of the soul which is mind, as opposed to the outer man, that part of the soul that involves sensation of bodily things and bodily life. Thus sensation is not part of the mind for Augustine, even if it is part of the soul. And the life of the mind is effectively distinguished and isolated from what we share in common with animals.

Echoing his analysis of the Holy Trinity, the term mind, like 'God', is said absolutely of memory, intellect, and will, and it signifies being or substance; memory is mind, intellect is mind, and will is mind. The terms memory, intellect, and will, like 'Father', 'Son', and 'Holy Spirit' are said relatively, that is, with reference to another. Thus, Augustine's thesis is that memory, intellect, and will are not three minds, but one; and these are not powers or faculties of the mind; they are the three distinct acts of the one mind.

There are a number of points in Augustine's analysis that need to be noted before I move on to discuss his influence on St. Thomas' early account of the mind. First, there is the simple truism that one has a mind, as well as what it consists in. In the beginning, Augustine had asked rhetorically, "what after all is so intimately known and so aware of its own existence as that by which things enter into our awareness, namely the mind"(p.248) Second, there is the methodological procedure of turning within, and away from the body and a presumed knowledge of sense objects. The methodological focus upon the mind apart from the body and its acts finds its justification in the major distinction within the soul between the outer man and the inner man. The outer man is the soul focussed upon its relation to body, while the inner man is the soul focussed upon the spiritual and the inner presence of eternal truth. However, this is not simply a nominal distinction, as if two words of different sense applied to the same thing. It finds its justification in a distinction within the soul between the mind, and the principle that Augustine speaks of enigmatically as "quickening" the body. He writes:

Anything in our consciousness that we have in common with animals is rightly said to be still part of the outer man. It is not just the body alone that is to be reckoned as the outer man, but the body with its own kind of life attached, which quickens the body's structure and all the senses it is equipped with in order to sense things outside.

Whether this "life" of the body that "quickens the body's structure" is a principle distinct from the soul, or is a part within the soul is left unclear by Augustine. That it is not part of the soul is suggested when he writes that it is the body's "own kind of life attached." On the other hand, that it is a part of the soul is suggested when he writes "we observe that we share even with animals those other parts of the soul which are impressed with the likenesses of bodies."(p.293) This would seem to suggest that whatever "quickens the body's structure and all the senses" is a part of the soul of which mind is another distinct part, rather than a distinct soul of the body. In any case, what is clear is that it is distinct from the mind, since it is not the role of the mind to "quicken the body's structure and all the senses." And the mind itself has a special unity apart from the lower powers of the soul.

Recalling Kenny, the parallel with what he called psyche stands out, as is the consequent methodological turning away from the life of the body as an appropriate part of the philosophy of mind. Indeed, the life of the body and sensation plays the same role in Augustine's discussion as it does in Kenny and Kenny's account of Aquinas, namely, as an external foil against which to study the mind, as something to be turned away from to reach a clearer and more pure understanding of mind. So, if we look to Augustine, Kenny seems to be right about how mind distinguishes us from animals.

The Augustinian Mind in Aquinas' Quaestiones disputatae de veritate.

In the De veritate Aquinas devotes question 10 to the topic of mind. It was delivered in the second year of his first Parisian regency, between 1257-58, more than a decade before he produced the commentary on Aristotle's De anima, and the "Treatise on Man." The theme of the question is Augustinian, as it is entitled, "concerning the mind, in which there is an image of the Trinity, and in the first article it is asked, insofar as there is in the mind an image of the Trinity, whether the mind is the essence of the soul, or some power of it." Augustine is cited mostly in the objections, which establishes his place as the authority for the question at hand. And all but one of the citations come from books IX-XIV of the De trinitate, the source of my discussion of Augustine. Indeed, the structure of the question itself follows Augustine's plan of turning from the outer man to the inner, and then upward to God, as Aquinas begins by asking about the mind's cognition of material things, then its knowledge of itself, and then whether God can be known in this life, finally ending with the question whether the Trinity of Persons can be known in this life through natural reason.

However, it would be a mistake to conclude that this Augustinian background excludes the very strong presence of Aristotelian themes throughout the discussion, as if Aristotle were for all practical purposes unknown in the discussion. Nothing could be further from the truth. The issue at play throughout the entire question is how to incorporate Aristotelian themes within the discussion of the mind as imago dei in Augustine's De trinitate. The tension shows itself in a number of ways. In the body of the response Aquinas clearly affirms that the mind is a power of the soul and not its essence. "The mind is said to be the highest power in our soul."(6) But the image of God is said to be in us according to what is highest in us, and so the image of God is only in us insofar as it is in the mind. Thus the mind, as containing the image, designates the power not the essence. Aquinas introduces here an Aristotelian theme that the soul itself is named from its highest power, which here he asserts is mind. So the soul itself can be called mind, secondarily and by analogy. Augustine, on the other hand, had been very careful to avoid calling the human soul a mind because of its function of "quickening" the body, a function that is shared with animal souls. Aquinas has no such qualm.

This willingness to call the entire soul by its highest power enables Aquinas to handle a distinct challenge from the authority of Augustine. Recall that Augustine had written that memory, intellect, and will are "one mind, one essence, one life." And it was clear in Augustine that these three are not distinct powers of the soul, but three acts of the mind. But there was that ambiguity in Augustine about the mind and the soul. The mind seems to be what is essential to, and the substance of the soul; but Augustine had not identified the mind with the whole soul, having made the distinction between the part of the soul that is the mind, and the sensitive part that "quickens" the body. But then the problem for Aquinas, brought about by the Aristotelian analysis of powers, is that against the authority of Augustine he has identified the mind with a distinct power of the soul, not its "essence or substance." And in the body of the response had he made no reference to memory, intellect, and will, the Augustinian triad. He had only written of understanding. He wrote:

'Mind' or 'mens' is taken from the verb to measure (mensurando)….So, the word mind is applied to the soul in the same way as understanding is. For understanding knows about things only by measuring them.

It is on the basis of its being said in the same way as 'understanding' that mind is said to be the highest power of the soul, such that the soul is appropriately called by the same name.

But in the responses to the objections, he will introduce the trinity of memory, intellect and will So, in response to the fifth objection, he explicitly takes up Augustine's thesis about the unity of the mind, only to reaffirm that these are three powers. Nevertheless, explaining what Augustine "meant" he writes, "these three are one essence insofar as they proceed from the one essence of the mind,…, one mind insofar as they fall under the one mind as parts under a whole, just as sight and hearing fall under the sensitive part of the soul." It is easy to overlook that here he is using 'mind' in two different senses. When he says "one essence insofar as they proceed from the one essence of the mind," he is using mind in the analogous sense in which it applies to soul, since the powers flow from the essence of the soul. But when he says that they are "one mind insofar as they fall under the one mind as parts under a whole," he is using 'mind' in its proper sense as applied to the highest power of the soul, as the comparison to the sense powers makes clear.

Aquinas also introduces an Aristotelian principle that he employs throughout the question, taken from De anima II.4 (415a14-16), where Aristotle begins to discuss his own classifications of soul against the background of his predecessors. The principle is that souls are distinguished by their powers, powers are distinguished by their acts, and their acts are distinguished by their objects. This Aristotelian principle is the cornerstone for at least one clear way in which Aquinas departs from the Augustinian background of the De trinitate, toward a more distinctively Aristotelian position. He does this by employing a second Aristotelian principle, namely, that a thing is known only insofar as it is in act. The mind, however, can only be known from its powers. But from the second principle, it follows that the powers can only be known from their acts. But then from the first principle it follows that the powers can only be known by their objects, since it is their objects that distinguish their acts. However, Aquinas argues that the proper object of the human intellect is the understanding of material nature. Therefore, insofar as the other powers of the mind come into act consequent upon the act of intellect, it follows that the mind can only be known by knowing how it engages the material world. But its engagement with the material world presupposes acts of sensation. Thus, it follows that the proper study of the mind essentially involves a consideration of the body and its sense powers, a clear rejection of the Augustinian methodological claim that the mind can only be known clearly insofar as it turns away from its prior and alienating engagement with the body and the sense powers. Study of sensation is an integral part of the philosophy of mind for Aquinas, not a contrast or foil. For Augustine the mind separated from the world is transparent to itself, while for Aquinas it is more or less opaque apart from the world.

And in answer to the question whether God can be known in this life through his essence, Aquinas employs the distinction that is familiar from the Posterior Analytics, between demonstration quia that God exists and demonstration propter quid about what God's existence consists in. Because of the orientation of the mind to material nature the first demonstration is available to natural reason, while the second escapes it.

So it would be a mistake to think of Aristotle's influence here as slight or occasional. It permeates the discussion, and sets the stage for most of the dialectic with Augustine. Nonetheless, the controlling theme is Augustine's discussion in the De trinitate. All of the articles are about the mind, not the soul. Despite the argument above about the need in the study of the mind to understand how the body engages the material world through the sense powers, in practice very little is said of the soul, other than the discussion of how memory, intellect, and will flow out of the essence of the soul as some of its powers.

More importantly, even if the soul can be called mind from its highest power, the mind is not identical with the soul. I noted how Aquinas argues that memory, intellect, and will are a unity by arguing that they are distinct powers flowing from the essential unity of the soul. But of course, if that is how they are a unity, then for the very same reason they form a unity with the powers of growth, nutrition, reproduction, all the powers of sensation, and so on. All the powers of the human soul flow from its essential unity. But then in that sense, the mind forms a unity with all the powers of the human soul. And there appears to be no particular philosophical reason for singling out memory, intellect, and will for special consideration as the subject of a disputed question, much less a philosophy. But from Augustine the mind is supposed to be recognizable as a special unity of three, memory, intellect, and will, recognizable even to those who cannot recognize it as an image of the Holy Trinity. What the light of faith adds to the recognition of this mental trinity is the ability to see in it an Imago Dei, "as in a mirror darkly."

Why then for Aquinas should the mind rather than the soul be singled out for special consideration as the topic of the disputed question? Why isn't this the disputed question on the soul that Aquinas will deliver eight years later as he embarks upon his commentary on the De anima, and the writing of the "Treatise on Man?" Because here he is concerned with a theological question the governing authority of which is Augustine's discussion of the mind. Like Augustine before him, and unlike Aristotle, Aquinas is pursuing a discussion of the image of God in the mind of man. However, if there is no mind, there is nothing to be discussed. So the key to understanding Aquinas' disputed question is his ability to find a special Augustinian unity in the mind that constitutes its special status, over and above the Aristotelian unity its powers share with all the powers of the human soul as flowing from its essence.

It is in the response to the objections to the first article that we observe Aquinas finding just such a special unity. In response to the second objection, Aquinas had argued that considering intellect and will as issuing from the essence of the soul, will is "on a par with(7) intellect," as opposed to the inferiority of the other appetitive powers. This is an important point for him to make, since in the actual body of the response he had not actually discussed the trinitarian character of the mind, but simply associated it verbally with understanding. Now in engaging the authority of Augustine he develops what he had done in the body of the response. "mind includes within it will and intellect, without at the same time being the essence of the soul, insofar as it names a certain class of powers of the soul."(8) However, all that is asserted here is that the mind denotes a collection of the highest powers of the soul. It does not assert that there is a unity to those powers that goes beyond the unity they possess as powers of the soul.

This response is important, however, because it singles out will as "on a par" with intellect as opposed to all the other powers of the soul. Recall that Augustine had said that they are equal. A year later Aquinas will abandon this position when he delivers question 22 of the De veritate, which is addressed to the will itself. In article 10 of question 22, he argues that the will and the intellect are distinct powers of the soul. Then in article 11, he argues that taken simply the intellect is a power superior to the will. And it is interesting to note that throughout question 22, the term mind disappears from the discussion. The major terms used are 'soul', 'intellect', and 'will'. 'Mind' occurs only twice, in both instances within objections, one quoting Augustine's De trinitate on the image of God, and the other paraphrasing Aristotle's claim in the Metaphysics (1027b20-25) that truth is "in the mind." In the latter case, the objector uses 'mind' as a straightforward synonym for 'intellect', but in his response Aquinas does not use 'mind' at all, but rather 'intellect'. In responding to the quotation from Augustine, he substitutes 'intellective part of the soul' for 'mind'. At this point, this may just be a terminological shift, since by the intellective part Aquinas clearly has in mind intellect and will. And that is not inconsistent with, but rather reflects the class of powers that he had said 'mind' names back in question 10. So perhaps mind or the intellective part of the soul is nothing more than that class of powers, which leaves unanswered the question as to whether they possess any special unity beyond the unity they share with all of the powers of the soul.

However, returning to the objections in article 1 of question 10, lest we think that the mind is merely a collection or classification of the higher powers of the soul, we can turn to the response to the seventh objection, where we see Aquinas finding just the special unity of intellect and will required. The objector argues that "acts that are specifically different do not come from one power. Yet Augustine says that [memory, understanding, and will] all come from the mind. Therefore, [since these acts are specifically different], the mind is not a power of the soul, but is the essence of the soul itself." Aquinas responds,

Just as the sensitive part of the soul is not understood to be some one power over and above the particular powers contained within it, but is a certain potential whole containing all of them as parts, so also the mind is not some one power over and above memory, intellect, and will, but is a certain potential whole containing these three, just like we see that the power to build homes contains the power to cut stones, and erect walls.(9)

Here we see Aquinas arguing that the three form a potential whole, distinct from that formed by the sensitive powers. Thus the mind is a part of the soul, not simply a classification of its highest powers, just as the sensitive part is not simply a classification of its lower powers. The members of the mental class form a distinct potential whole within the soul.

However, the character of that potential whole may still seem somewhat ambiguous, since Aquinas says that it is not a power over and above the other powers. Then what is it? It is a power of the soul, as the body of the article, and the response to the next objection, number 8, inform us. The objection had argued that mind must be the essence of the soul, since a power of the soul cannot be the subject of other powers. However the mind, as Augustine had said, is the subject of the image of the Trinity which is constituted by memory, intellect, and will. Aquinas responds:

When 'mind' names the power itself, it is not compared to the understanding and the will as subject, but more as whole to parts. But if 'mind' is taken for the essence of the soul, according as it naturally flows as a power from the soul, then it names the subject of the powers.(10)

Recall that one of the results of Aquinas' response to the article was that the soul could be named from its highest power which is mind. But 'mind' properly speaking names a potential whole constituted by the powers of memory, intellect, and will. And that potential whole, as this response tells us, is itself a power, while the subject of any power is the soul.

But then it appears that there is a conflict with the response to the seventh objection, since it had said that the mind is not a power over and above the three powers, while the response #8 seems to suggest that it is. The mind is not identical to memory, intellect, and will each taken singly. So, not being identical to them but containing them, it seems it has to be a power over and above them. The conflict is resolved in the very next response to objection 9, the last objection and response of the article. The objector had argued that "no power includes within itself many powers. But the mind includes intellect and will. Therefore it cannot be a power, but is the essence of the soul." Aquinas responds that "one particular power does not include under itself many powers, but nothing prohibits many powers as parts from being included under one general power, just as under one part of the body are included many organic parts, the fingers under the hand, for example." So the mind is a potential whole of three powers, that is itself a power, but it is a general power as opposed to the particular powers that it unites.

In the case of the mind, then, we are to think that memory, intellect, and will are like the fingers of the hand. We can analyze them in thought apart from the mind, but they cannot exist as the powers that they are apart from the power of the mind. They cannot do what particular powers do if they are not united as constituting the general power of the mind, just as fingers cannot do what fingers do except as integral parts of a hand. So the power of the mind just is the powers of memory, intellect, and will; it is not a power over and above them. Indeed, here, in the Aristotelian language of powers, we see Aquinas beautifully succeeding in preserving precisely Augustine's strong emphasis upon the image of the Trinity in the unity of the mind constituted from the three; a unity of one thing absolutely, and yet constituted from three relatively.

So the mind as a part of the soul has its own special unity beyond the unity of the soul, and is thus distinguished from the sensitive part of the soul that we share in common with animals. This is just the philosophy of mind that Kenny had argued is to be found in the Summa Theologiae written more than a decade later, the joint power essentially constituted from intellect and will It is now appropriate to turn to the Summa to see if Kenny is correct in his assessment of it.

Aquinas and the Summa Theologiae on Mind(11)

There a three parts to my argument about the Summa, the first semantic, the second systematic, and the third properly philosophical. The discussion of the first two is much more expansive in the paper, but here I just one to say something brief about them, in order to go right to the philosophical claim.

The Semantic Claim

In this section I show that in the Summa, 'mens' is just a synonym for 'intellect'; contrary to Kenny's claim, they are just two words for the same thing, said in the same way. Generally, in the "Treatise on Man," and in the discussion of the imago dei itself, if Augustine is quoted as asserting that mind is composed of intellect, memory, and will, Aquinas will time and again interpret that as the manner of speaking by analogy in which mind or intellect applies to the soul, or where will is associated with intellect or mind. But no suggestion is made that there is a general power including memory, intellect, and will. Indeed, the usefulness of comparing his analysis in the Summa with the De veritate is clear, since it makes it obvious that Aquinas is trying to avoid that general power. So, careful attention to how Aquinas actually uses the term mind shows that Kenny has not grasped what it means in the Summa discussion.

But let me consider one particular instance. In question 82, article 3, Aquinas raises the question of whether the power of intellect is a power higher than the will, the issue he raised in question 22 of the De veritate. Recall that he argued there that the intellect is absolutely speaking a higher power, against the Augustinian position of their equality that he had taken a year earlier in question 10. In question 22, Aristotle was quoted in one of the objections as saying that truth is in the "mind or intellect." But in his response, Aquinas made no use at all of 'mind', and confined himself to using only 'intellect'. Here in the Summa discussion, by contrast, Aquinas argues the same point that intellect is a higher power than will. But the difference is that now he uses the quotation from Aristotle in his own response:

The philosopher says that good and evil which are the objects of the will, are in things; the true and the false which are objects of the intellect, are in the mind.

But this clearly uses 'mind' as a synonym for 'intellect' as distinguished from 'will'. If we look at the appropriate place in Aquinas' commentary on the Metaphysics, we see the expression over and over, namely "in the mind, that is, in the intellect," ("in mente, idest in intellectus"). The reason for this use of 'mind' seems to be that where Aristotle's Greek text had 'dianoia' or 'thought', so that the sense of the text is that 'the true and the false are in thought', the Latin translation that Aquinas had has 'mente' for 'dianoia', not 'intellectus'. Thus, it is Aquinas who is explaining that by 'mente' or 'mind' we should understand 'intellectus' or 'intellect.' The clarification is his, not something in the Latin text of the Metaphysics (1027b20-25) that he is looking at. And I think the explanation of this is clear. He had commented on the De anima three years earlier in 1268. But the De anima for all practical purposes doesn't use 'mens', but rather 'intellectus'; and in the few instances in which it does use it, it is a straightforward synonym for 'intellectus'. One important instance in the De anima commentary is when he quotes this same Metaphysics passage in the discussion of intellect's acts of simple and complex understanding at L.III, lc.11. But throughout the entire discussion he had been using 'intellectus', not 'mens'. 'Mens' only appears in the direct quotation from Aristotle; indeed it is one of only two instances of the term 'mens' throughout the whole commentary on the third book. Thus, in reading the Metaphysics passage, when he writes "in the mind, that is, in the intellect," he is simply rendering it consistent with the De anima text that he knew so well from his commentary.

The Systematic Claim

Briefly, the systematic claim is that there simply is no discussion of the joint power in the Summa. There is a discussion of the soul, its powers, the distinction between the sensitive powers, intellect, and will, but no discussion of the joint power essentially constituted from intellect, and will. Given that it was present in the De veritate, why not here in the Summa?

The Philosophical Claim

So, granted that Aquinas does not use the term 'mens' to refer to the thing that Kenny describes, and granted that the Summa contains no discussion, philosophical or otherwise, of the thing that Kenny describes, isn't it still possible to mine the Summa for Aquinas' philosophical insights that can be suitably extended and applied to the thing that Kenny describes? Even though he never discussed it, what would Aquinas have to say about it, given what he does write in the Summa. After all, the philosophy of mind is now understood to be one of the core areas of contemporary philosophy, a subject that Kenny believes will always give philosophers something to do; to be relevant to today, musn't Aquinas and contemporary Thomists have something to say about it? No. My claim is given what he does say, Aquinas would deny that there is any such thing as Kenny describes, which brings me to the properly philosophical substance of my argument.

There are at least two very good Aristotelian reasons why there should be no such discussion of mind. The first has to do with the object and act of the mind. To be sure, the acts of intellect and will do not occur in isolation from one another; their interaction is very intimate for Aquinas. (I.82.4) The will like an efficient cause moves the intellect to its act, while the intellect provides the intelligible form of the will's movement. But they do not come together in a common power. Why? Kenny has the resources to answer this question, were he to ask it. In question 77, article 3 Aquinas argues that powers of the soul are distinguished from one another by their acts, which are in turn distinguished by their objects. We saw that this principle from De anima II.4 was present in the De veritate discussion; and Kenny makes extensive use of it throughout his work, but especially in his chapters 10 and 12. 'Object' here does not have the contemporary metaphysical sense of 'thing that exists' or 'value of a bound variable', but rather whatever affects a passive power, or whatever the goal is of an active power. Aquinas uses color as the object of vision for an example of an object of a passive power, and physical maturity as the object of an active power like growth. And of course we might say the object of chess is to mate one's opponent, without thereby positing some thing in the world. Kenny summarizes Aquinas' discussion this way:

Powers are specified by their exercises (S 1, 77, 3). That is to say, you can only understand what the power to φ is if you know what φing is. One power differs from another if its exercises and its objects differ; for instance the ability to swim is different from the ability to fly, because swimming is different from flying; and the ability to bake bread is different from the ability to bake biscuits, because bread is different from biscuits.(12)

Thus, the principle requires that one determine the powers of the substance, for example, a human person, by an analysis of the acts engaged in by the substance. A brief way to describe the principle is like this: what does the power do? Unless you can say what the power does, what it achieves, there is no reason for the Aristotelian to posit the existence of a power. There is a danger, as Kenny puts it, of "multiplying powers without multiplying their exercises."(13)

But, though Kenny applies the principle to the intellect alone, and to the will alone, in his analysis of Aquinas on mind, he never bothers to stop and ask much less answer, "what does the mind do?" Intellect has its object, universal truth. Will has its object, universal good.(I.82.4.ad 1). But then, according to the Aristotelian principle, if the mind is a power other than the intellect alone, and other than the will alone, it must have a determinate act that distinguishes it from these powers. We don't want to "multiply powers without multiplying their exercises." But what is that act? If we proceed according to the Aristotelian principle, we must distinguish its specific act by its specific object. So what is the specific object of mind? If it is a passive power, what distinctly affects the mind? If it is an active power, what does the mind distinctly achieve? Do the objects of intellect and will combine to form a joint object of mind, namely the true-good, or the good-truth, as opposed to the false-good, or the bad-truth? No, according to Aquinas, the good and the true are found wherever being is found. It is the act of intellect to respond to the truth of being, while it is the act of will to move toward the goodness of being. The transcendenatl unity of truth and goodness that is found in being is not reflected in a joint power that essentially unites will and intellect. That unity is to be found in the soul, for which intellect and will are powers, the soul that is the first principle of life of a human being whose telos is to live the good life of a rational animal informed by the truth of things.

But, if we look back at the De veritate, it is clear that Aquinas simply takes the existence of the mind for granted from Augustine's discussion, in order to specify what it is, not that it is. Aquinas uses the principle in the De veritate to distinguish will from intellect, and both from the sense powers. But he himself never applies it to the mind. In other words, he never tells us what it is that the mind does. By contrast, Augustine's mind is absent from the Summa, precisely because it has nothing to do, and Aquinas now knows it.

In his own account of mind, The Metaphysics of Mind, Kenny had said that the mind can be defined as "the capacity for behavior of the complicated and symbolic kinds which constitute the linguistic, social, moral, economic, scientific, cultural and other characteristic activities of human beings in society."(14) Roger made reference to this passage the other day. But Kenny offers no good argument that there is any such capacity. At best he has given a nominal definition of a term that might be used in an argument to show that there is such a capacity. But simply defining it nominally does not make it so; otherwise there'd be unicorns and philosophies of them. Kenny simply takes 'mind' to be a successful referring expression, and attributes that commitment to Aquinas. Descartes thought simple reflection upon oneself made it impossible to doubt that one is a thinking thing. Kenny, on the other hand, thinks that simple reflection upon one's activity of reading makes it clear that one has a mind. He writes, "you have a mind, as is proved by the fact that you read and understand what I have written."(15) But the existence of the mind doesn't follow from that. What follows, by Kenny's own analysis of the terms, is that I have an intellect, since it is the intellect that is the power to comprehend and manipulate symbols; it might follow that I have a will, since presumably I have chosen to engage in the act of reading. But it very definitely doesn't follow that I have a power that is essentially constituted from intellect and will. As if sensing this failure, Kenny subsequently adds "that human beings in general have minds and bodies…is simply a truism,"(16) which is to say, in no need of proof.

Thus, Kenny offers no good argument that the complexity of his description of the capacity he calls mind involves a single unified object, which he would have to do in order to justify the conclusion that such a power exists whose act is distinguished by that object. Indeed, there is no reason for thinking that the description refers to anything more than a complex of objects and acts united by the principle of human life, the soul not the mind of a rational, social, political animal like man. Kenny seems to forget that among the libraries, and concert halls, and stock markets, one finds the economic transactions of grocery stores, the construction of sewers, the licensing of sex, and the certification of birth. Just think of the great leap forward taken by human civilization when the Bodleian got indoor plumbing; who cares about landing on the moon.

The second Aristotelian reason for denying that there is a mind has to do with the definition of man: man is a rational animal. Kenny writes, "in the scholastic jargon, animal is the genus, man is the species, and 'rational' indicates the specific difference which marks out the species within the genus."(17) However, Aquinas writes in the Summa (I.76.4 ad 4) that we can consider what is common to man and other animals separately from that in which they differ. What is common is sensation, and the genus animal is taken from this commonality. The difference is taken from the "something more" that a man can do that other animals cannot, namely, reason in virtue of his intellect. Though Kenny eschews consideration of Aquinas' commentary, this is the general movement of Aristotle's De anima as it considers the hierarchy of souls from the vegetative, through the sensitive, to the rational, with each grade of soul including within itself the powers of the soul below it; and it is here that the familiar principle from the De anima that the soul is named from its highest power finds its greatest application. Kenny goes on to note that "a specific difference is, according to Aristotelian theory, a form. Therefore the intellectual principle which is denoted by the word 'rational' must be the human being's form."(p.145) Kenny then goes on to identify the highest power with the mind, the joint power of intellect and will as he has analyzed it. So, if he is right, we would expect that the definition of man would be mental animal, and this would mean something more than rational or intellectual animal. We saw that this is precisely what Aquinas does say in the De veritate, that man is called a mental animal from his highest power. But he does not write this in the Summa, preferring always to say rational animal. Why not? Because there is no such thing as the mind essentially constituted from intellect and will.

I think that here Aquinas' negative position in the Summa on the plurality of souls debate is crucial for understanding this absence of mind in Aquinas. Aquinas argued for the unity of the vegetative, sensitive, and rational principles in the human being, against those who would assign a principle or principles for the vegetative and sensitive life of the human being, and another distinct principle for the rational or mental life of the human being, which second principle would include within it the intellect and will. One can see the seed of this 13th century debate in the ambiguity of Augustine's treatment of the soul and mind, as the soul quickened the body, and yet had a mental life clearly distinguished from the life of the body, a mental life so distinct that Augustine identified a part of the soul, the mind, with the substance and essence of the soul, and spoke only fleetingly of its "quickening" function. And it was to a certain extent ambiguous whether the quickening principle was a part of the same soul of which the mind was a part. What the later plurality of souls position does is clarify Augustine's ambiguity in favor of separating clearly the animal life from the mental. Now in the 13th century, employing Aristotelian terms, it is clear that the human being, having two principles of life, in effect lives two lives. He lives the life of an animal animated by his animal soul, and he lives a distinct mental life animated by his mental soul. So the definition mental animal, in its manifest complexity tracks two distinct forms of life, one higher and another lower. It distinguishes the human species from the genus animal, in the sense of separating or "setting off" rational life from animal life.

On the contrary, for Aquinas we live but one life, the life of a rational animal. Aquinas argues that the principle of rational life just is identically the principle of animal life in the human being. Thus the life of the mind or intellect just is identically the life of the animal. He takes this position explicitly in order to preserve the integrity and unity of human life.

If it were the case, therefore, that a man lives from one form, namely the vegetative soul, is an animal from another form, namely the sensitive soul, and is a man from another, namely the rational soul, it would follow that a man would not be absolutely one thing.(S.T. I.76.3)


Therefore it is necessary that it is the same form through which a thing is an animal, and through which it is a man; otherwise a man would not truly be an animal, and so animal could not be predicated in the definition of man.(S.T.I.76.3)

Both of these quotations come from question 76, so we see the fateful step that Kenny takes when he says Aquinas' philosophy of mind starts only in question 79. The second quotation leaves absolutely no doubt about Aquinas' desire to emphasize the absolute unity of human life in all its manifestations; animal could not be included in the definition of man, if the principle of animal life were not identically the same as the principle of rational life in man. Of course the argument goes both ways, and the conclusion also follows that rational could not be included in the definition of any animal; no animal could "truly be" rational. On the contrary, for Aquinas, to be an animal and to be rational is the same form of life in a human being. So, the definition rational animal distinguishes the species not in the sense of separating or "setting off" distinctively human mental life from animal life. Rather it distinguishes the form of life that being an animal takes in being human. It displays the character of animal life in a human being as rational, as the life of an animal that eats reasonably, reproduces reasonably, grows reasonably, and employs the senses reasonably, or at least ought to given what he is; rational is not a distinct principle preceding these bodily acts and interacting causally with them, but the human form of them. Now someone might object that Aquinas argues that the act of intellect is a non-bodily act, and therefore cannot be an animal act. But that only follows if every act of an animal is the act of a bodily organ. And that is precisely the point at issue. When Aquinas argues that the act of intellect is not the act of a bodily organ, he is not showing that there is a non-animal act engaged in by human beings. He is showing, rather, that not every act of an animal is a bodily act.

Now in question 10 of the De veritate, Aquinas shows no concern at all about the plurality of souls debate. And we recall that there he maintained the special unity of the mind apart from all the other powers of the soul in order to preserve Augustine's analysis in Aristotelian terms. On the other hand, the plurality of souls debate is one of the main initial topics in the "Treatise on Man." I claim that Aquinas drops the Augustinian power of mind that he had argued for in the De veritate, precisely because it left the door open for separating the mental life of man from his animal life almost exactly in the way that the plurality of souls position does. His opponents could very easily argue on Aristotelian grounds that if the mental life of intellect and will has the special essential unity that Aquinas attributes to it in the De veritate, apart from the essential unity of the soul shared with animals in the sensitive life, then such a special essential life can only be justified by a principle of mental life distinct from the principle of animal life. To resist that move could only be ad hoc on Aquinas' part.

So, by eliminating Augustine's mind in the Summa, Aquinas is effectively eliminating any suggestion that to be human is to be anything other than an animal whose form of life is rational. So the duality manifest in the definition rational animal does not correspond to a duality in the thing defined. On the contrary, the unity of the two elements of the definition corresponds to the absolute unity of the form of human life. The unity of intellect and will is not preserved in a special power that separates man from animals. Rather it is preserved in the unity of the soul that unites man to animals, insofar as it specifies the form that animal life takes in being human.

After Descartes, the problem with Aristotelianism, even for those like Kenny who eschew Cartesian metaphysics and introspective philosophical psychology, is that Aristotle wrote a De anima, not a De mente. What we see Kenny despairing of, in his defense of the philosophy of mind, is any serious philosophical study of the unity of human life. The natural life sciences study in an empirical way how we are similar to animals, while philosophy studies in a non-empirical way how we differ from animals. But there is no discipline, it seems, that studies what it is like to be a human animal, an animal whose form of life is rational. Does the mind distinguish us from animals, or does it distinguish us as animals?

"We are up against one of the great sources of philosophical bewilderment: a substantive makes us look for a thing that corresponds to it."(18) Insofar as we have a term, 'mind' that functions as a referring term in our use, we assume that there must be some thing, the mind, that it refers to. Kenny's assumption of the legitimacy of the philosophy of mind is a primary example of that fundamental mistake pointed out by Wittgenstein on the first page of the Blue Notebook. Aquinas did not make that mistake. What Kenny misses is that Aquinas does not share the Cartesian obsession with consciousness, precisely because he does not share the Cartesian obsession with the mind.

The Larger Picture: Cartesian Philosophy of Mind versus Aristotelian Psychology

I don't want to end here, since it might give the impression that the whole point is to win a chess game with Anthony Kenny on the interpretation of Aquinas. Kenny thinks Aquinas is important to contemporary philosophy of mind and so do I, but obviously for different reasons. But I can only make a speculative suggestion. It is precisely Aquinas' commitment to the unity of human life in the soul that Thomists can contribute to contemporary philosophy of mind. Kenny straightforwardly assumes the legitimacy of the methodological dualism that for all practical purposes is the soul of contemporary philosophy of mind. Kenny had described how the progress of science has carved away at the philosophical disciplines present in Aristotle's corpus. Still, the philosophy of mind is an element of the "irreducible core amenable only to philosophy." Just as Rick and Ilsa will always have Paris, we philosophers will always have the philosophy of mind. The empirical sciences describe man empirically, while the philosophy of mind describes mind non-empirically but philosophically. As far as I am concerned this is just as much an expression of the "dread chasm that has rent the soul of Western man ever since the famous philosopher Descartes ripped body loose from mind and turned the very soul into a ghost that huants its own house,"(19) as are the metaphysical dualism and private instrospection of Descartes that Kenny rightly opposes.(20) But he leaves us with a study of the distinctively human, the mental that "set us off" from other animals, the "[thinking] thing that doubts, understands, affirms, denies, is willing and unwilling."(21) [One need not advocate the type-type identity theory of Smart and Place, to recognize the importance of the Cartesian turn taken in contemporary philosophy when it was rejected.]

What we Thomists need to insist upon and argue for is that this Cartesian methodological dualism fails to capture either human life empirically or the mind philosophically. We need to correctly identify the problem, the loss of form, of substantial form, and of soul, and remedy it. The temptation is to think that the mind tacks some level of reality on to the biological and physical life we share with animals. That additional reality of mind somehow engages biological life, and explains it by providing some mysterious causal relations. Here I think all the different varieties of reductive materialists in the philosophy of mind have grasped a Thomistic truth in the midst of the error of reductive materialism. They insist upon the unity of human life. Even the bete noir of philosophy of mind, Paul Churchland who argues that there is no mind, recognizes that when he tries to give an Ethics for eliminative materialism. What these reductionists lack is the natural principle of form, and in this case soul. We need to recover the understanding of the plurality of the sciences as modes of abstraction from the unity of being, rather than hermetically sealed conceptual schemes that need to be identified one to another, reduced, or eliminated.

If we return to Kenny's own description of mind, that it is "the capacity for behavior of the complicated and symbolic kinds which constitute the linguistic, social, moral, economic, scientific, cultural and other characteristic activities of human beings in society,"(22) it is obvious that one cannot adequately reflect upon that complex reality without taking into consideration that we are living bodies. And if that reflection is going to be well informed, it must be informed by our scientific knowledge of ourselves as living bodies. On the other hand, we do not adequately understand our human growth, nutrition, and reproduction, those characteristics that at one level of description we share with animals and plants, if we do not understand it as reasonable and chosen. Just consider growth, the least obvious. It is surely conditioned and limited by the biological properties that at one level of description we share with other animals. And yet, when I was 10, my parents would not let me drink iced tea, because they said, "it will stunt your growth." Perhaps that was empirically false, but just consider if you will my beer belly. What do you think I should do about it? You know, and I know. I'm just not sure I have the will to follow through.

Now it is important not to misunderstand. Adverting to the intellectual and volitional aspect of human life does not provide a causal explanation of human bodily behavior; it provides the adequate description of human bodily behavior that is to be explained. The walking of a dog and the walking of a human share a description. But when we provide the description they share we have not yet provided an adequate description of what the human being does, so that we can even try to find any causal explanation of it. When we have provided an adequate description of human walking, which involves intellect and will, we no longer have a description that applies to dogs. And it is then that we can go about looking for an adequate explanation of a human walking. What we are doing here is recognizing the form of human action, and specifying its characteristics. In doing so, we recognize and specify the soul of a rational animal. I cannot confess to understanding quite what Wittgenstein himself means, so I rather more steal than quote from him: "my attitude towards him is an attitude towards a soul. I am not of the opinion that he has a soul," and "the human body is the best picture of the human soul."(II.iv.178)

The death of the soul in modern philosophy is the slow death of the mind, as the recent history of philosophy of mind suggests. Thomists need to be arguing for the reanimation of the mind, not contributing with Kenny to its funeral oration.

John O'Callaghan
Creighton University

1. Brian Davies, Religious Studies, p.128-130. James Ross, Philosophical Quarterly, p.534-537. 1993. Ross comes closest to a negative review of the book. Deborah Black, Journal of the History of Philosophy 33:2 April 1995. pp.338-341. C. J. F. Williams, International Philosophical Quaterly, vol. XXXIV, No. 3. (Septermber 1994) pp.375-376. Robert Pasnau, The Philosophical Review, vol. 103, no. 1 (October 1994). pp.745-748. John Haldane, ..., pp.242-244.

2. p.20.

3. p.291.

4. p.273

5. Bk.10, chpt.4, p.298

6. My translation.

7. "in eadem coordinatione cum intellectu" Schmidt trans.

8. "... huiusmodi potentiae secundum quod egrediuntur ab essentia animae, quae est subiectum earum, voluntas invenitur in eadem coordinatione cum intellectu;.... Et ideo mens potest comprehender voluntatem et intellectum, absque eo quod sit animae essentia; inquantum, scilicet, nominat quoddam genus potentiarum animae, ut sub mente intelligantur comprehendi omnes illae potentiae quae in suis actibus omnino a materia et conditionibus materiae recedunt." Quaestiones Disputatae de veritate, Thomas Aquinas. Turin: Marietti, 1948. 10.1 ad 2. From here on referred to as QDV.

9. My translation.

10. My translation.

11. Note: I am addressing the Summa discussion because that is where Kenny says the philosophy of mind is to be found. However, it is worth noting that the shift from earlier to later takes place earlier than the Summa. There is no discussion of mind in St. Thomas' disputed question on the soul, nor in the Summa Contra Gentiles.

12. Kenny, p.155.

13. p.156-157.

14. ibid..

15. The Metaphysics of Mind, p.17.

16. ibid., p.18..

17. p.145

18. The Blue and Brown Books: the Blue Book, Ludwig Wittgenstein. New York: Harper & Row, 1965. p.1.

19. Love in the Ruins, Walker Percy. New York: Avon Books, 1978. P.181.

20. Finally, there are striking parallels with Descartes. It is certainly well known that Descartes was indebted for his cogito, ergo sum argument to Augustine's si fallor sum argument, as it can be found in any number of works, including The Confessions, the Contra Academicos, and On Free Choice of the Will. Less well remarked are other parallels. Consider the determination of the essential characteristics of mind.

Nobody surely doubts,…, that he lives and remembers and understands and wills and thinks and knows and judges. At least, even if he doubts he lives; if he doubts, he remembers why he is doubting; if he doubts, he understands he is doubting; if he doubts, he has a will to be certain; if he doubts he thinks; if he doubts, he knows that he does not know; if he doubts, he knows that he ought not to give hasty assent. You may have your doubts about anything else, but you should have no doubts about these; if they are not certain, you would not be able to doubt anything.(p.296)

Consider also the fundamental principle for arguing that the mind cannot be a body. Both argue that the mind is only what it is certain that it is; it is not what it is not certain that it is. Augustine writes,

we are concerned now with the nature of mind; so let us put aside all consideration of thing we know outwardly through the senses of the body, and concentrate our attention on what we have stated that all minds know for certain about themselves.(p.296)… Let[the mind] set aside what it thinks it is, and mark what it knows it is; in this way it will be left with something even people who have thought mind is this or that sort of body can have no doubt about.(p.296)…If [the mind] refrains from affixing to itself any of these image-bound objects of its thoughts in such a way as to think it is that sort of thing, then whatever is left to it of itself, that alone is what it is.(p.297)

Where , who in the De trinitate had written:

these three [memory, understanding, and will] are one in that they are one life, one mind, and one essence. And whatever else they are called in respect to themselves, they are called together, not in the plural but in the singular.

21. Meditation 2, p.83. Cottingham, Stoothof, Murdoch.

22. ibid..