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A Brief Interlude

What is surprising about all of this, when considered from the historical distance of more than a half-century, is that, while the twin characteristics of philosophical realism and an adherence to the role of common sense permeated the discussions of the early analytic philosophers, as well as the later work of Wittgenstein, Ryle, and Austin, the great realist philosophers of the Aristotelian tradition were, for all practical purposes, overlooked, neglected, and ignored. The analysis put forward in this chapter suggests that this oversight is a conceptual pity. The Aristotelian philosophy of mind tradition, especially as found in the writings of Thomas Aquinas, offers insights regarding the nature of sensation and perception that might have moved these perception discussions forward in important ways. Hence, the analysis of philosophical concepts found in the writings of Aquinas, especially as spelled out in his detailed Commentary on Aristotle’s De Anima, are philosophical themes with much more than historical interest. These discussions encompass analyses of intentionality theory, adopting a role of common sense, rendering a distinction between sensation and perception, elucidating a naturalistic philosophy of mind, treating what Davidson once called an ‘anomality of the mental’, rejecting what Putnam refers to as ‘the inner theatre of the mind, and finally transcending the limits of British empiricism. Putnam’s denial that the mind is an ‘inner theatre’ is akin structurally to the common-sense philosophy of mind defended by Aquinas.[1] Putnam’s ‘inner theatre’ model is a direct reference to representationalism, which is familiar in all Cartesian and Lockean philosophy of mind and is found in Russsell’s writings.

In responding to Russell and others, representationalism entails that efficient causation is a sufficient condition to explain sensation and perception. Secondly, representationalism assumes what McDowell and Putnam call ‘the highest common factor’ for a veridical awareness and a non-veridical awareness (e.g. an illusion). Both Putnam and McDowell suggest, on the other hand, that this analysis is a ‘disjunctive account’ lacking the common factor that most representationalists assume. This account suggesting the lack of a common property linking sense perception with illusion is most helpful in understanding Aquinas on intentionality theory, for Aquinas too acknowledges this disjunction. In writing about direct realism—what he sometimes refers to as ‘natural realism’—Putnam comments on McDowell’s work along the same lines, which is similar to what Aquinas might have said:

McDowell argues persuasively that this picture, whether in its classical version or in its modern materialist version, is disastrous for just about every part of metaphysics and epistemology. In McDowell’s terminology the key assumption responsible for the disaster is the idea that there has to be an interface between our cognitive powers and the external world. [. . .] Accounts of perception that reject this claim are conventionally referred to as ‘direct realist’ accounts. [. . .] But there is less to some versions of ‘direct realism’ than meets the eye. [. . .] All one has to do to be a direct realist about visual experience, for example, is to say, ‘We don’t perceive visual experiences, we have them. [. . .] ‘We perceive external things—that is, we are caused to have certain subjective experiences in the appropriate way by those external things’, such a philosopher can say.[2]

While agreeing with this account in both Putnam and McDowell, Haldane raises the question about how this account of direct realism is possible. Like Aquinas, Haldane requires as a necessary condition some connection between the object in the external world and our intentional awareness of that object. It is at this juncture that Haldane, reverting to his Aquinas thrust, requires some account of both an efficient cause and a formal cause. This aspect of formal cause is a necessary condition in order for Aquinas to render an account of direct realism. One must take Aquinas literally here—there is a strict, formal identity of form between the knower and the known. This is what Aquinas means when he claims, Sensus in actu est sensible in actu, and Intellectus in actu est intelligible in actu. What makes knowledge possible is that the form known is identical with the form in the thing. This holds for both sense knowledge and intellectual knowledge. Haldane comments: ‘What does this mean? And how is it possible? It means that when I think of something, that which makes my thought to be the kind of thought it is [. . .] is formally identical to that which makes the object of my thought to be the kind of thing it is.’[3]

This concludes the extended analysis of Principle D-1, which is the foundational claim upon which Aquinas builds his thesis of intentionality.

  • [1] Hilary Putnam, Aristotle’s Mind and the Contemporary Mind, in Demetra Sfendoni-Mentzou,Jagdish Hattiangadi, and David M. Johnson (eds), Aristotle and Contemporary Science (New York: Lang,2000), vol. 1, 7-28.
  • [2] Hilary Putnam, ‘Sense, Nonsense, and the Senses: An Inquiry into the Powers of the Human Mind, Journal of Philosophy 91(9) (1994), 453-4.
  • [3] Haldane, ‘A Return to Form in the Philosophy of Mind, 54. A cognitive capacity has the ontologicalpower to have an esse intentionale, which is that by means of which a thing in the external world is known.
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