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The Awareness of Individuals

In the case of a human perceiver in contrast with a sensing animal, Aquinas refers to an important change regarding the act of awareness of this internal sense: what in animals is the vis aestimativa in humans is the vis cogitativa. There is, however, at least an analogous relationship between the vis aestimativa in animal sensing and the vis cogitativa in human knowledge. Passages in the Summa Theologiae continue the discussion of sensation and perception:

Now, we must observe that regarding sensible forms there is no difference between human persons and other animals. For they are similarly immuted by external sensibles. [...] But there is a difference as to the above intentions [i.e. of the internal senses and intentiones non sensa- tae]: for other animals perceive these intentions only by some sort of natural instinct, while human persons perceive them also by means of a certain comparison. Therefore, the power which in other animals is called the natural aestimative in humans is called the cogitative, which by some sort of comparison discovers these intentions. Therefore, it is also called the particular reason, to which medical persons assign a particular organ, namely, the middle part of the head. For it compares individual intentions, just as the intellectual reason [intellectus possibilis] compares universal intentions. (Summa Theologiae, I q. 78 a. 4)

In this passage, Aquinas notes clearly that the vis cogitativa is neither identical nor coextensive with the instinct associated with the vis aestimativa. It follows that, regarding content, there are no innate ideas in the cognitive capacities in human per- ceivers. Rather than being natural instinct, the vis cogitativa makes comparisons regarding the awareness of individual things. The vis cogitativa is that sense faculty by means of which the human perceiver is aware of an individual as an individual—i.e. as a concretum—and not merely as a bundle of conjoined proper and common sensibles. Aquinas writes about the vis cogitativa: ‘[It . . . ] distinguishes individual intentions and compares them with one another’ (Summa Contra Gentiles, bk II, ch. 60). Aquinas writes that a human knower may consider ‘universal notions, which belong to the intellectual faculty, or about particular matters, which belongs to the sensitive faculties [ . . . the latter being . . . ] an act of the cogitative power’ (Summa Theologiae, I—II art. 1). It appears that the concept of ‘comparison’ is reducible to a comparison of one individual primary substance with another. In other words, this is the faculty or cognitive power with the built-in ability to be aware of a specific individual as an individual and thus, by comparison, separate one incidental object of sense from another. One might ask whether the animal ‘perceives’ the object of which it is afraid as an individual, or only as a collection of proper and common sensibles. Aquinas is unclear on this distinction. It appears, however, that what is perceived—i.e. what would be the epistemological force of the vis aestimativa—is reducible to an innate reaction, e.g. fear, in the very act of perceiving itself. This might be similar to a Gestalt conditioning of the act of awareness of a fearful object.

Aquinas writes the following about the vis cogitativa; several texts are included here because this topic is central to the general overall theme of this study.

Having seen how we should speak of the absolute or essential sense objects, both common and proper, it remains to be seen how anything is a sense object ‘incidentally’. Now for an object to be a sense object incidentally, it must first be connected accidentally with an essential sense object; as a human person, for instance, may happen to be white, or a white thing may happen to be sweet. Secondly, it must be perceived by the one who is sensing. If it were connected with the sense object without itself being perceived, it could not be said to be sensed incidentally. But this implies that with respect to some cognitive faculty of the one sensing it, it is known, not incidentally, but absolutely. Now this latter faculty [ . . . ] (is) the vis cogitativa. (Commentary on the Soul, no. 395; emphasis added)

This faculty is part of the ‘machinery’ of sensation and perception for Aquinas:

But, speaking precisely, this is not in the fullest sense an incidental sense object; it is incidental to the sense of sight, but it is essentially sensible. Now what is not perceived by any special sense is known by the intellect, if it be a universal; yet not anything knowable by intellect in sensible matter should be called a sense object incidentally, but only what is at once intellectually apprehended as soon as a sense experience occurs. (Commentary on the Soul, no. 396)

Aquinas suggests that the act of awareness of the vis cogitativa is of ‘something incidental’:

Thus as soon as I see anyone talking or moving herself, my intellect tells me that she is alive and I can say that I see her alive. But if this apprehension is of something individual, as when, seeing this particular coloured thing, I perceive this particular person or beast, then the cogitative faculty (in the case of human persons) is at work, the power which is also called the ‘particular reason’ because it correlates individualized notions, just as the ‘universal reason’ correlates universal ideas. (Commentary on the Soul, no. 396)

Later in the Commentary, Aquinas argues that the incidental object of sense is not directly perceived by any external sense:

Thus I perceive indirectly that so and so is Cleon’s son, not because he is Cleon’s son, but because he is white. Whiteness as such only happens to be connected with Cleon’s son. Being the son of Cleon is not (like sweetness) indirectly visible in such a way as to imply its being directly perceived by some other sense. (Commentary on the Soul, no. 580)

Aquinas writes that the vis cogitativa ‘is always of a man as this man, and of a tree as this tree’ (no. 398). This faculty of inner sense, therefore, is aware of a human person as this particular human person and of a tree as this particular tree. A dimension of ‘this particular, concrete thing’ becomes important for Aquinas’s theory of perception. The direct object of the act of awareness of the vis cogitativa is the particular individual as a primary substance. This primary substance is not reducible to a mere collection of incidental or essential properties. This kind of awareness is beyond the limits imposed by a ‘bundle’ view of perception articulated by most empiricists.[1]

Klubertanz argues that the function of the vis cogitativa is akin structurally to the vis aestimativa. He writes: ‘In St. Thomas, the vis cogitativa is the human estimative, concerned with the singulars of action [operabilia] as standing under the intelligible light of reason.’26 Klubertanz thus limits the vis cogitativa to ‘practical knowledge’. Hence, he also argues that what Averroes proposed for the virtus cogitativa differs fundamentally from what Aquinas proposes. Klubertanz suggests that for Averroes, the virtus cogitativa functions in the following way: ‘[It] is a kind of aestimative and compositive imaginatio, concerned with the singulars corresponding to intelligible knowledge (singular substance, singular accidents, individual substantial differences, and so forth).’27 What the analysis articulated in this book argues, to the contrary, is that the vis cogitativa, at its core, has more than the practical function Klubertanz puts forward. It is akin structurally to what Klubertanz proposed for the virtus cogitativa of Averroes. The vis cogitativa is the faculty of inner sense whereby, by means of intentiones insensatae, the human knower is aware of an individual—a primary substance—as an instance of a natural kind. The role of practical knowledge follows after the individual as individual is known. What is surprising is that even Klubertanz, in sketching the differences between Averroes and Thomas on the object ofthe vis cogitativa, notes that for Aquinas the object is ‘the individual as standing under a common nature; this person as this person.28 Yet Klubertanz, it appears, cannot get beyond his paradigm of interpretation for the vis cogitativa as directed only towards particular actions to be undertaken—the ‘operabilia’ of the passage noted above.

In a passage from his early Commentary on the Sentences, Aquinas, at this formative stage of his prolific philosophical career, was cognizant of the role of a per accidens object of sensation:

Per accidens is sensed which does not affect the sense inasmuch as it is a sense, nor as it is this sense, but as joined to these things which of themselves affect the sense, as ‘Socrates’ and ‘the son of Diares,’ and ‘friend’ and other like things. These things are known in the universal by the intellect; in the particular, they are known by the discursive power [vis cogitativa] in human persons and by the estimative [vis aestimativa] in other animals. Such things the external sense is said to sense, even thought only per accidens, when from that which is sensed in itself, the apprehensive power [the vis cogitativa] whose task it is to know them in themselves, immediately, without hesitation or reasoning, knows them; as we see that someone lives from the fact that she speaks. (In IVSent., 49 q. 2 a. 2; emphasis added) as something intelligible. Qua sensible, a physical particular is something material, which has (or is an aggregate of) sensible properties: colors, smells, weight, solidity, extension, shape, etc. These are all properties that we perceive by the senses’: Kurt Tranoy, ‘Aquinas’, in D. J. O’Connor (ed.), A Critical History of Western Philosophy (New York: Free Press, 1964), 105. It is unclear what Tranoy is referring to as the ‘physical particular’. If it is the hoc aliquid in the external world, then Tranoy has adopted a reductionist view and posits that the physical object is nothing but ‘an aggregate of sensible properties’. This would be the bundle view adopted by Berkeley and Hume. This denies any role for the incidental object of sense and for the vis cogitativa in Aquinas’s account of perception. This proposal put forward by Tranoy appears consistent with many such accounts offered of Aquinas’s analysis of sensation and perception by mid-20th-c. historians of philosophy.

26 Klubertanz, The Discursive Power, 278-9. 27 Ibid., 278. 28 Ibid., 278.

Commenting on this extended passage from the Commentary on the Sentences, Klubertanz writes: ‘St. Thomas is here writing on a problem of immediate perception.’29 Yet Klubertanz does not develop this point, which he claims is a ‘single text in the Scriptum Super Sententiam’. In his Quaestiones Disputatae de Veritate, Aquinas, however, writes: ‘This power is also called the discursive, and it has a definite organ in the body, which is the middle cell of the head. Now it is not possible to apply the universal judgment [...] to a particular act, except through some intermediate power that apprehends the singular’ (De Veritate X, 5).

White initially mentions the important role that the vis cogitativa plays in Aquinas’s account of perceiving the individual, and explains that this is a necessary condition for explaining the abstractive process of the intellectus agens. ‘[In] the Commentary on the Posterior Analytics [...] Aquinas makes it clear that the cogitative power’s apprehension of “this human” is a necessary condition for the intellectual apprehension of “human”. ’[2] White then goes on, much like Klubertanz, to argue that the principal function of the vis cogitativa is in determining actions to be undertaken in the here and now (hic et nunc). He fails to pursue the important insight that he gathered from his reading of the Commentary on the Posterior Analytics, where Aquinas writes:

Then [at 100a4] Aristotle elucidates something asserted in the preceding solution, namely, that the universal is taken from experience bearing on singulars. And he says that what was stated above, albeit not clearly—namely, how from the experience of singulars the universal is formed in the mind—must now be discussed again and explained more clearly. For if many singulars are taken which are without differences as to some one item existing in them, that one item according to which they are not different, once it is received in the mind, is the first universal, no matter what it may be, i.e. whether it pertains to the essence of the singulars or not. For since we find that Socrates and Plato and many others are without difference as to whiteness, we take this one item, namely, white, as a universal, which is an accident. Similarly, because we find that Socrates and Plato and the others are not different as to rationality, this one item in which they do not differ, namely, rational, we take as a universal, which is an essential difference. (Commentary on the Posterior Analytics, lect. 20)

In the next paragraph, Aquinas argues that the sense powers must render a contribution to the intellectual powers before it is possible to explain how, as Aristotle argues, ‘the universal comes to be in the soul’. Aquinas continues:

But how this one item can be taken he now explains. For it is clear that sensing is properly and per se of the singular, but yet there is somehow even a sensing of the universal. For sense knows Callias not only so far forth as he is Callias, but also as he is this human person; and similarly Socrates, as he is this individual human person. As a result of such an attainment pre-existing in the sense, the intellective soul can consider human nature in both. But if it were in the very nature of things that sense could apprehend only that which pertains to particularity, and along with this could in no wise apprehend the nature in the particular, it would not be possible for universal knowledge to be caused in us from sense-apprehension.

29 Ibid., 175-6.

Then he manifests this same point in the process, which goes from species to genus. Hence he adds: ‘Again in these, namely, in human nature and horse, ‘the mind lingers in its consideration, until it attains to some thing indivisible in them, which is universal’. For example, we consider such an animal and another one, say an individual human person and an individual horse, until we arrive at the common item, ‘animal, which is universal; and in this genus we do the same until we arrive at some higher genus. Therefore, since we take a knowledge of univer- sals from singulars, he concludes that it is obviously necessary to acquire the first universal principles by induction. For that is the way, i.e. by way of induction, that the sense introduces the universal into the mind, inasmuch as all the singulars are considered. (Commentary on the Posterior Analytics, lect. 20)

In these often overlooked texts from Commentary on the Posterior Analytics, Aquinas is quite specific that sense, by which he means the vis cogitativa, renders an indispensable contribution to the process of explaining abstraction in his adoption of Aristotle’s philosophy of mind. In the Summa Contra Gentiles, often Aquinas refers explicitly to the vis cogitativa: ‘For, since the cogitative power is operationally limited to particular things, makes its judgements on the basis of particular intentions, and acts by means of a bodily organ, it is not above the generic level of the sensitive soul’ (Summa Contra Gentiles, bk II, ch. 73, no. 14). ‘Nor, again, does the cogitative power bear any ordered relationship to the possible intellect whereby a human knower understands, except through its act of preparing the phantasms for the operation of the agent intellect [intellectus agens] which makes them actually intelligible and perfective of the possible intellect’ (no. 6). ‘Moreover, the dispositions of the cogitative and imaginative powers are relative to the object, namely, the phantasm, which, because of the well-developed character of these powers, is prepared in such a way as to facilitate its being made actually intelligible by the agent intellect. Now, dispositions relative to objects are not habits, but dispositions relative to powers are habits’ (no. 28; emphasis added). ‘Even so, it can be said that the agent intellect is, in itself, always acting, but that the phantasms are not always made actually intelligible, but only when they are disposed to this end. Now, they are so disposed by the act of the cogitative power, the use of which is in our power’ (Summa Contra Gentiles, bk II, ch. 76, no. 8).

This role for the vis cogitativa is a necessary condition to explicate fully what Aquinas means by perception. In his essay on ‘Instinct and Custom, White suggests that in the writings of Thomas, there are three roles or functions exhibited by the vis cogitativa.[3] Nonetheless, White’s account, while more thorough than most classical and recent commentaries, is but a partial rendition of the roles that the vis cogitativa exercises in Aquinas’s philosophy of mind. All three of these roles depend upon some awareness by the vis cogitativa of the individual primary substance, which is the cause of these various mental activities. Hence, a principal role of this power of inner sense is to be able to use the intentio non sensata as a means to perceive directly the individual hoc aliquid. Once the knowing ability of the vis cogitativa to be aware of this holistic object of perception is elucidated, the other three roles mentioned by White fit together in a more coherent and structured whole.

It is somewhat surprising that Stump spends little time and space with the internal sensorium: ‘in what follows, I will consider only phantasia and imagination among the internal senses.’[4] Stump, it appears, does not grasp the two uses that Aquinas has for phantasia: (a) phantasia as equivalent to the vis imaginativa, which Aquinas use in the Prima Pars of the Summa Theologiae; and (b) the use of phantasia in the Commentary as a generic umbrella term for the three faculties of the internal sensorium: the vis imaginativa, the vis cogitativa, and the vis memorativa. Furthermore, she appears to identify the vis aestimativa with the vis cogitativa: ‘In human beings, the estimative power compares “individual intentions”, as the intellect compares universal intentions’[5] Kemp also blurs these two faculties.[6]

Pilsner too avoids discussion of the vis cogitativa as well as any analysis of the incidental object of sense. While it is correct that the principal focus of Pilsner’s treatise is on undertaking an analysis of Aquinas on moral actions, nonetheless he believes that an analysis of the objects of sensation, perception, and intellectual understanding are necessary conditions in order to understand fully these concepts that are foundational in Aquinas’s overall philosophy. Pilsner provides a sophisticated analysis of the role of the proper and common sensibles in Aquinas’s writings. He then refers to ‘a third category of qualities [. . . that] include incidental properties which can be “sensed” only through their association with the sensibles already mentioned’.[7] What is interesting in Pilsner’s analysis is that he suggests that it is ‘incidental properties’ that are known by the vis cogitativa and the vis aestimativa. The argument to be explored, however, suggests that it is the incidental object of sense—the individual primary substance also called the hoc aliquid—that Aquinas postulated as the sensible object of the vis cogitativa. Hence, it is not a set of properties that is known by the vis cogitativa, but the individual primary substance itself existing as a hoc aliquid. Pilsner, in a rather comprehensive table of objects, acts, and powers, does suggest that the inner sense faculty of the vis cogitativa has as its object ‘intentions.[8] This is more than likely rooted in a reading of Avicenna. However, Pilsner leaves this important philosophical concept hanging in the air, avoiding any analysis of what it might mean. Later in his chapter, Pilsner considers a substance—what he means by a ‘primary substance’—but he avoids any discussion about how this individual entity might be known.

  • [1] In his mid-century analysis of Aquinas’s philosophy, Tranoy provided at best a muddled account ofwhat the object of perception is for Aquinas: ‘This is to say that from an epistemological point of view anyphysical particular presents two different aspects. We can know it, first, as something sensible, and secondly,
  • [2] A. Leo White, ‘Instinct and Custom’, The Thomist 66 (2002), 578.
  • [3] ‘This higher level of awareness is reflected in the three roles that Aquinas attributes to the vis cogitativa in humans. The first and most obvious role—one that roughly parallels that of the vis aestimativa inbrutes—is to evoke the passions that help energize our actions. The second role has to do with the way thatthe cogitative power enables universal reason to apply its judgments to particular individuals during practical reasoning. The third role is the cogitative power’s preparation of the phantasm for abstraction’: ibid.,380-81.
  • [4] Stump, Aquinas, 248. 33 Ibid.
  • [5] 34 To quote Kemp (Medieval Psychology, 57-8): ‘Indeed, Thomas Aquinas believed that there were onlyfour inner senses and discarded the cogitative power completely on the grounds that the power to combineimages was unnecessary for animals, and performed by the imagination alone in humans.’ Kemp confusesthe vis imaginativa with the vis cogitativa. In the account of inner sense in the Prima Pars of the Summa
  • [6] Theologiae, Aquinas explicitly keeps these two faculties of inner sense separate and distinct.
  • [7] Joseph Pilsner, The Specification of Human Actions in St Thomas Aquinas (Oxford: Oxford UniversityPress, 2006), 93.
  • [8] Ibid., 100.
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