Primary Substance and the Vis Cogitativa
An important corollary of this discussion is the role that primary substance plays in the functioning of the vis cogitativa. For Aquinas, the fundamental category of things in the external world is a primary substance. His ontological realism is one of individual substances in the space-time realm. A primary substance is an individual thing of a certain natural kind. ‘Natural kind’ refers to a species or common nature, which is determined by the substantial form of the thing. The vis cogitativa is the faculty of inner sense by which the perceiver is aware of a primary substance as a thing and not merely a thing reducible to a bundle of sensations. This mental awareness requires an interpretive function on the part of the vis cogitativa. In effect, with the vis cogitativa, inner sense is going beyond the data of the external sensorium. Moreover, inner sense is more than the acts of introspection common to modern philosophical discussions. Accordingly, not only does Aquinas have primary substances in his ontology, but his philosophy of mind is structured so that it is possible for the perceiver to be aware of these primary substances. Simply put, the vis cogitativa explains the possibility of the awareness of individual concreta, which are primary substances. The end result is that Aquinas affirms both that there are individual things in the external world—an aspect of his ontological realism—and that human knowers are aware of these individual things—an aspect of his epistemological realism. The possibility of being aware of things as individuals is accounted for by means of the phantasm-structured vis cogitativa. The external sensorium is limited to an awareness of unified wholes of proper and common sensibles. The vis cogitativa is aware of the primary substance that renders an awareness of the ‘unified whole’ into an awareness of an individual of a natural kind.
In discussing how an individual perceiver is aware of an individual, Stump argues that this occurs only because of the interplay between inner sense and the intellect. She writes: ‘for Hannah to see what is presented to her vision as a cat requires what Aquinas calls the first operation of the intellect, namely, determining the quiddity or whatness of a thing.’ She goes on to suggest that Aquinas uses the contemporary epistemological distinction between ‘seeing and seeing as’. Yet ‘seeing as’ requires the intellect: ‘sensory powers and phantasia are sufficient for seeing without being sufficient for seeing as.’ The focus of the analysis for the vis cogitativa developed in this chapter, however, is that on the level of perception a human agent can undertake ‘seeing as’; this results in Aquinas being able to distinguish between sensation and perception. The vis cogitativa has a necessary role to play in his philosophy of mind. This rendition adds a perceptual dimension to Stump’s analysis, which requires (so she argues) the immediate working of the intellectus possibilis.
Accordingly, Aquinas posits the vis cogitativa in order to account for human awareness of what Aristotle calls the ‘incidental object of sense’. By ‘incidental object of sense’, both Aristotle and Aquinas mean that a human perceiver is aware of this bundle of sensations [X] as Cleon’s son and this other bundle of sensations [Y] as Cleon’s daughter, and this white patch [P] as snow and this other white patch [Q] as flour. This awareness goes beyond the immediate data of sensation—i.e. the ‘concrete wholes’ that are the unified conjunctions of the proper and the common sensibles. Yet human perception, Aquinas suggests, is not exhausted by mere sense data. He continually stresses this point: ‘But the senses have also their indirect objects, and with regard to these they can be deceived. What seems to be white is indeed white as the sense reports. But whether the white thing is this or that thing, is snow, for example, or flour, is a question often answered badly by the senses, especially at a distance’ (Commentary on the Soul, no. 662).
The importance of this sense faculty in Aquinas’s philosophy of mind is obvious. One of the experienced data of the perceptual lives of human knowers, the pre-analytic data, is that perceivers are directed primarily towards an awareness of things rather than only to an awareness of collections of qualities or qualia. Accordingly, Megan, as a perceiver, is aware of Elin—as an individual—and not just a collection of proper and common sensibles. Contemporary philosophers, who claim that human knowers ordinarily talk as if they perceive things and not sense data, point out this same pre-analytic datum. Aquinas undercuts the sense data theories of early twentieth-century epistemology and the empiricism of Locke, Berkeley, and Hume by suggesting, in effect, that our experience is of things rather than of sense data. In addition, by using a metaphilosophical methodology entailing a faculty psychology, Aquinas provides the philosophy-of-mind machinery necessary to explain the possibility of an act of awareness of an object beyond the immediate data of the proper and the common sensibles. Once again, there is a similarity to Strawson, who claims that particulars—individual particular things—are the basic elements of a human perceiver’s conceptual scheme. Accordingly, Aquinas, like Strawson, Ryle, Wittgenstein, and Chisholm, suggests that it is a mistake to claim that human perceivers are primarily aware of bundles of sense data. To the contrary, human perceivers have a direct ‘thing consciousness’ or ‘individual consciousness’ Furthermore, this ‘consciousness’ and ‘intentional awareness’ are rudimentary for human perceivers.
In order to explicate this faculty of inner sense, it is appropriate to compare the acts of awareness of the vis cogitativa with what one common-sensibly refers to as ‘experience’. The first time Megan sees Elin, she obviously does not recognize her as Elin. Nonetheless, Megan perceives an individual of a natural kind. As far as being Elin to Megan the perceiver, on the level of the external sensorium alone, Elin is no more than a mere bundle of sensations. Of course, with the structured mental act of the vis cogita- tiva, Megan perceives an individual person of a natural kind, which is more than is possible using the external sensorium alone. Yet after Megan has got to know Elin, then she immediately recognizes Elin ‘as Elin’ as soon as Elin comes into view. It is important to realize that Aquinas is not claiming that Megan remembers this particular bundle of sensations—i.e. the concrete whole—as Elin. Rather, she perceives her to be Elin, the individual of a natural kind. Yet ‘being Elin’ is not an ontological property that is directly perceivable in the external world. ‘Being Elin’ is not a proper or a common sensible, which are the only two categories of objects of direct sense experience in the external sensorium. This is an important part of Aquinas’s theory of sense perception; thus, Elin is an incidental or accidental object of sensation. Accordingly, Megan is directly aware that this ‘concrete whole’ is Elin—a particular individual of a natural kind. That such an individual property is unperceivable per se is consistent with Aquinas’s position on individuation. The ontological problem of individuation is resolved in his metaphysics by the assertion that ‘materia prima signata quantitate’ is the principle of individuation. Following Aquinas’s principles of intentionality, only a form can be knowable directly. Since materia signata, which is the direct opposite of a form, is the individuator, there is nothing as such in the external world that could be the object of the mental act of direct sensation regarding an individual as an individual. Hence, there is no specific form of individuation per se. It is apparent that Aquinas and Scotus differ radically on this point, given Scotus’s individual form of haeccaeitas. Metaphilosophically, Aquinas builds his epistemology from the demands of his ontology. Aquinas does not move from epistemology to ontology. Given his metaphilosophy conjoined with his ontological realism and his externalism, it would seem odd that in his philosophy of mind he would neglect to provide the necessary machinery for a perceiver to be aware of those very external objects that constitute a significant primacy and fundamental role in his ontology. The active contribution on the part of the vis cogitativa in its acts of intentional awareness enables Aquinas to account for the perception of individuals. This structured mental act accounts for the isomorphism. It is as if the vis cogitativa is ‘always on the go, as it were, attempting to be aware of individuals as primary substances. Aquinas accepts the fact that this kind of awareness is a pre-analytic datum; in other words, human perceivers have a ‘thing consciousness’ and not a ‘quality consciousness’. The vis cogitativa accounts for the possibility of how this pre-analytic datum—the awareness of an individual concretum—can be explained. Put simply, the vis cogitativa is ‘hard-wired’ by intentiones insensatae to perceive the external world in terms of individuals of natural kinds. Accordingly, Aquinas makes use of the vis cogitativa as the faculty of the internal sensorium, which accomplishes our awareness of individuals and not just of ‘concrete wholes’.
-  Stump, Aquinas, 261.
-  Often this sense object is translated as ‘the accidental object of sense’. This indicates that the meaningof this sense object is that its content is beyond what is attained by the external senses.
-  Chisholm referred to this as a ‘particularist epistemology’: Roderick Chisholm, The Problem of theCriterion (Milwaukee, Wis.: Marquette University Press, 1973), 12-14. Chisholm argued for the priority of ‘thing consciousness’ for epistemology rather than for a ‘bundle view’.
-  Cf. De Ente et Essentia, ch. 2. In this early text, Aquinas considers in some detail the role matter playsas the individuator of individuals; see also the Commentary on The Metaphysics, bk XII.
-  Once again, Haldane’s recommendation becomes important; Aquinas’s metaphilosophy is one ofexplanation and not justification.
-  The question of the nature of phantasms is of critical import here. The analysis of this concept isforthcoming following discussion of the nature of an intentio non sensata.