It’s Not Just Physical

In the last three posts in this series on mind-body interaction, we looked at some of the more serious objections to what is known as “interactionist ‘substance’ dualism”. After laying out a litany of difficulties with this model, I ended the previous entry by asking why anyone would defend such a view.

There are several reasons. Let’s look some of them over.

The most obvious problem arises from the uniqueness of the phenomenon in question. Materialist science concerns itself with the objectively observable features of the world, but the subjectivity of my conscious experience means that it is available only to one observer only, namely me. These subjective “experiencings” — the redness of an apple, the taste of a Martini, the painfulness of pain — are known as qualia, and nothing else that science has ever examined is like them. It is difficult to see how any description of brain activity, physical states, or electrochemical processes will ever “explain” my qualia. As a commenter at Maverick Philosopher put it in a recent thread:

“Now could it be true that all of my sensing, perceiving, thinking, etc. is just complex processes transpiring in my brain and central nervous system?”

In short, NO, for it’s an incoherent notion.

Just insert the elided word: ‘…complex material processes…’. As in micro-neuro-biochemical processes, which science has revealed are nothing but atoms bumping into each other. Now exactly where in that bustling arena of meaningless atomic motion do I find the ‘sensing, perceiving, thinking, etc.’?

Nowhere. Therefore that notion doesn’t make ‘prima facie sense’. Nothing in that picture of complicated processes but thoughtless protons, electrons, and neutrons, responding 1E26 times per second to the zero-point field, and incidentally, far more slowly to some extremely minor perturbations we call molecular forces.
(I believe Locke raised this objection long ago but I guess it’s been ignored ever since.) No room left over for reductionism, eliminativism, or epiphenomenalism. In principle, our mentality is wholly inexplicable in material terms.

Fair enough. Our mentality is inexplicable in material terms, given our current inventory of “material terms”. Another word that pops up often in this context is “unintelligible“.

But other aspects of the physical world have seemed “unintelligible” as well, until science formed a conceptual framework for them: magnetism, for example (how can a stone move another stone without touching it?) or the propagation of light waves through empty space (the existence of the luminiferous ether was considered an unassailable fact prior to the Michelson-Morley experiment, because of the “unintelligibility” of waves traveling through a vacuum). Despite this history of mystery yielding to comprehension through the slow and patient weathering of scientific effort, though, there are dualists who flatly insist that it is a settled fact that there can never be a materialistic account of consciousness. One of them, of course, is Dr. Vallicella himself, who, weary of my “maybe-it’s-just-too-soon-to-tell” objections whenever such blunt assertions were made, excommunicated me altogether. (I think it’s telling that he had also recently written this post, in which he expresses the view that there is little to be learned from history.)

Another argument in support of dualism has been given by philosopher David Chalmers, who invokes the idea of the “zombie”: something that looks like a person, and behaves just like a person, but that has no inner life whatsoever — no consciousness, no qualia, no experiencing at all. Chalmers argues that since we can imagine a zombie that is identical down to the smallest details of brain structure and activity, but which has none of the subjective experiences that we do, then there must be something that is “left over” after the physical description has been completely elucidated.

The strength of this argument depends on the assumption that because we can conceive of such zombies, they are actually possible. But this is not necessarily a valid assumption; this sort of question was examined by the philosopher George Seddon in a 1972 paper†† in which he asks us to conceive of a floating bar of iron. Iron does not float, as we know; if we imagine, then, a floating iron bar, something has to give somewhere. Either the bar is not what we usually mean by “iron” (a metal having a certain specific gravity, etc.), or it is not floating on “water”, or it isn’t really “floating”. In the same way, I suspect that Chalmers’ assumption that permits the existence of zombies that are physically indistinguishable from conscious humans may be an unjustifiable move, one based on our present ignorance of the physical underpinnings of consciousness.†††

There is also the issue of free will. For many, I think that one of the strongest motivations to accept a dualistic viewpoint is the reluctance to surrender our decisionmaking to a mechanism that proceeds according to everyday physical causality; this is seen by many as corrosive to our sense of moral responsibility, and indeed to our notion of ourselves as dignified autonomous agents. (I think this view is wrong, but to begin that discussion would be out of context here.) A dualistic model, while not answering all of the problems swirling around causality and will, does at least emancipate the mind from the shackles of merely physical causation, and I think that is a large part of its appeal. Note, however, that “it must be this way, because anything else would be just too awful” is not an argument, but merely a wish.

Finally, I think that many who endorse mind-body dualism are theists as well, and see our faculties of reason and moral responsibility as important aspects of our relationship to God. This is, of course, simply a matter of faith, as there are perfectly coherent accounts of both of these phenomena as products of our evolutionary history.

So, I think it might have been premature for Daniel Dennett to claim †††† that dualism has, as he puts it:

…been relegated to the trash heap of history, along with alchemy and astrology. Unless you are also prepared to declare that the world is flat and the sun is a fiery chariot pulled by winged horses — unless, in other words, your defiance of modern science is quite complete — you won’t find any place to stand and fight for these obsolete ideas.

In fact, despite the points outlined in this series of posts, mind-body dualism is alive and well, and remains, for the present at least, beyond conclusive refutation by either science or philosophy.

That doesn’t mean it isn’t wrong, of course.

Related content from Sphere
  1. Not that I’m angry, mind you — though I was certainly surprised, and more than a little disappointed. Dr. V. is under no obligation to provide a forum for dissenting views.
  2. †† G. Seddon, Logical Possibility, Mind, 81 (1972), pp. 481–94
  3. ††† For a more in-depth look at this objection to Chalmers’ argument, see this paper, by Tamler Sommers, of Duke University.
  4. †††† in Kinds of Minds, 1996, p. 24


  1. The ‘zombie’ is an attempt at rebuttal of the notion that there could not be an entity that was functionally identical with a human being that did not have consciousness. It suggests that we can envisage such an entity in the form of a zombie and the picture that we proffer does not explode out of internal incoherence. The answer to that might be – ‘yes, perhaps, but the well of plausibility that you draw from is tainted by dualism’ to which the zombie wallah would retort – your functionalism is a transcendental position of which no proof is possible’. To which again would come – ‘there is only the material’.

    Is the cure worse than the disease? I happen to think that Wittgenstein exorcised the ghost in the machine in ‘Philosophical Investigations’ and that since then dualists in Philosophy are as rare as the white rhino. The hylomorphic dualism that you have heard of is more correctly termed hylomorphism and its scholastic proponents would deny that it was a dualism at all.

    Outside philosophy you have dualism such as that of Freud who held that there could be sexuality without hormones as in infantile sexuality. That is an odd and dangerous delusion.

    Posted April 9, 2007 at 4:59 pm | Permalink
  2. Malcolm says

    Hi Michael,

    Well, that’s certainly an interesting comment.

    I’m not as sure as you are that philosophical dualists are as rare as you say; if their ranks are considered to include those theists who believe in immaterial souls, they certainly outnumber white rhinoceroses. I admit that this series of posts was inspired by one nest of rhinos in particular.

    My purpose, of course, in all of this, both here and elsewhere, is not to settle the issue of mind-body dualism pro or con; it is, rather, just to defend the position that the question is still open. It vexes me that there are those in the philosophical community who, although they rightly insist on a respectable degree of rigor when discussing other topics, imagine that they can simply declare this case closed on the basis of dismissive proclamations about “unintelligibility”, and about what mere matter can and can’t do. Intelligibility, of course, depends upon an appropriate conceptual framework — and as I point out above, history teaches us that with patient scientific effort, and the occasional spark of genius, such frameworks continually, and progressively, evolve, allowing us to understand phenomena that had previously been regarded as impenetrable mysteries.

    As for Freud’s assertion that sexual drives can manifest themselves in infants, I’ll reserve comment, other than to say that informed opinions may vary on that one.

    Posted April 9, 2007 at 5:16 pm | Permalink
  3. Thanks Malcolm,
    Just on the immortal soul. The soul is the form of the body which is an analogical extension of the matter and form distinction of substantial entities. The matter of the bronze ball is bronze and it form is its sphericality. Strictly then the soul ought not to be capable of separate existence any more than the smile of the Chesire cat. In the somewhat muddled Christian doctrine of post mortem existence this is recognised in the eventual re-union of soul and body in the Final Judgment. That for personal immortality there has to be a body is the inchoate realisation evinced by this doctrine which of course is blurred by the interim orphan state.

    In Vedanta the same sort of realisation is expressed through the device of the subtle body which is a bridge from the body that is dropped to the new incarnation. Again there is a body in the picture so I would claim that even in the after-life there is a resistance to a purely dualistic doctrine. Most believers can handle a little inconsistency.

    Posted April 9, 2007 at 7:03 pm | Permalink
  4. Malcolm says

    Hi Michael,

    Yes, I’m familiar with the hylomorphic model you describe; I think Bill V. described it nicely when he allowed, in an email, that to some it must seem like “medieval mumbo-jumbo”. It is riddled with difficulties, and while it appears that its internal coherence can, by the most strenuous philosophical contortions, just barely be defended, it astonishes me that anyone would take it seriously.

    The Vedantic model could perhaps be interpreted as a materialist doctrine, as you say. There are other teachings from nearby areas that posit various sorts of interpenetrating materiality; there’s too much there for this comment box.

    Posted April 10, 2007 at 12:12 am | Permalink