Wednesday, October 1, 2008

Some brief arguments for dualism, Part III

In the previous post in this series, I argued that the “mechanistic” conception of the natural world adopted by the early modern philosophers more or less entails a kind of dualism insofar as its banishment of final causes from the material world effectively makes intentionality necessarily immaterial. Intentionality, of course, is one of two features of the mind to which contemporary philosophers of mind have paid special attention. The other is consciousness, and in particular the “qualia” that are said to make consciousness uniquely difficult to explain in material terms. There is a good reason for this difficulty – indeed, impossibility – and it is the same reason why intentionality is impossible to explain in materialistic terms. It lies in the mechanistic conception of matter itself.

The early modern philosophers and scientists were obsessed with quantification. There were several reasons for this, one of them being their desire to reorient intellectual efforts toward the improvement of life in this world and away from the otherworldliness of the ancients and medievals. This entailed a new emphasis on technology and more generally on the control and exploitation of the natural world in the interests of bettering man’s material condition. Since quantification would facilitate this, those aspects of nature that could be described in purely mathematical terms took on a special importance, and those which could not came to seem, from the point of view of this new, worldly approach to learning, irrelevant at best and a distraction at worst. Thus did final causes, hidden powers, substantial forms and the like go out the window. So too did the qualitative aspects of nature. Colors, odors, tastes, feels, sounds, and the like, at least as understood by common sense, vary from observer to observer – think of old philosophical chestnuts like the room temperature water that feels warm to one hand and cool to the other, colorblindness, and so forth – making them a poor fit for a science looking to make nature subject to human prediction and control. Out the window with them too, then. The physical world would be redefined as comprised of colorless, odorless, tasteless particles in motion; and color, temperature, and the like would be redefined entirely in terms of the quantifiable relations holding between these particles (e.g. heat and cold in terms of molecular motion). What about color, odor, taste, and so forth as common sense understands them? They in turn were redefined as entirely mind-dependent “secondary qualities” (or rather, ideas of secondary qualities), the ancestors of the contemporary philosopher’s concept of qualia. On the view in question, they do not exist in the physical world as it is in itself, but only in our perceptual representation of that world.

It should be obvious, then, how, as with intentionality, the notion that qualia are incapable of materialistic explanation is not some desperate attempt to avoid the implications of modern science, but is rather precisely a consequence of modern science. The mechanistic conception of matter that underlies science (or rather underlies what, since the 17th century, is allowed to count as science) itself entails that qualia (as we call them today) are immaterial or non-physical. Many early modern thinkers – Descartes, Cudworth, and Locke, for example – saw this, which is part of the reason they were dualists. Given the mechanistic conception of matter, these thinkers concluded that “secondary qualities,” “sensory qualities,” “qualia,” or whatever else you want to call them are necessarily immaterial, precisely because matter got (re)defined by the mechanical philosophy by contrast with these qualities.

Some contemporary naturalists – Joseph Levine, Thomas Nagel, and John Searle, for example – have more or less recognized this, acknowledging that there is nothing more to the contemporary materialist’s concept of matter (which derives from the 17th century “mechanical” conception) other than its contrast with the “qualitative” (and intentional) features of our experience of the world. Precisely for this reason, all three of these thinkers have (in their different ways) regarded modern materialism as deeply conceptually problematic, though they have also stopped short of embracing dualism. But other contemporary naturalists – Dennett and the Churchlands, for example, not to mention countless lesser lights of the sort who write crude atheist pamphlets and pop neuroscience books – cluelessly suggest that there is no good reason to think that the mind will fail to yield to the same sort of reductive explanation in terms of which everything else in nature has been accounted for.

In fact there is a very good reason why the mind should be uniquely resistant to such “explanation,” and it precisely because everything that doesn’t fit the mechanistic-cum-quantificational picture of the natural world has not been “explained” by science at all, but simply swept under the rug of the mind and treated as a mere “projection.” This is true in particular of anything in nature that seems to smack of final causality or to have an irreducible qualitative (as opposed to quantitative) character. It is conceptually impossible that the mind itself should be “explained” in the same way – that is to say, by further sweeping – which is why modern philosophy has a “mind-body problem” of a sort that did not exist before the mechanistic revolution, and why all materialist attempts to “explain” the mind are really disguised versions of eliminative materialism. The tiresome canard that “everything else has already been explained in materialistic terms” is thus a gigantic shell game, pure sleight of hand, a complete fraud from start to finish. (This is a theme I first explored in my book Philosophy of Mind and develop at length in The Last Superstition.)

In any case, we have now a third brief argument for dualism, which can be summarized as follows: Given the materialist’s own (mechanistic-cum-quantificational) conception of matter, colors, odors, tastes and the like as we experience them do not exist in the material world itself; but these qualities do exist in our perceptual representations of the material world; therefore, there exist features of the world – namely these sensory qualities or “qualia” that characterize our perceptual experiences – that are not material or physical features.

Obviously this argument raises questions about how these immaterial features relate to the material ones – Are they basic or emergent? How can they causally interact with the material ones? Do they inhere in a physical or a non-physical substance? – but the fact that it raises them has no bearing on the cogency of the argument itself. My own view is that the standard (Cartesian) dualist answers to such questions are problematic precisely because they buy into the same mechanistic conception of matter to which materialists are beholden. The right approach is to challenge that conception of matter, and return to the Aristotelian-Scholastic picture it replaced. But whether I am right about this or not is also irrelevant to the argument just given, which does not assume any Aristotelian-Scholastic premises, but simply draws out the consequences of the very conception of matter to which materialists themselves are committed. Whatever the deficiencies of Cartesian dualism, they do not approach the sheer incoherence and cluelessness of contemporary materialism.

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