Wednesday, October 29, 2008

Some brief arguments for dualism, Part IV

The arguments for dualism considered so far in this series (see here, here, and here) have been more or less “modern” rather than “classical.” They focus on those aspects of the mind most familiar to contemporary philosophers, namely intentionality (the meaningfulness or directedness beyond themselves of thoughts and the like) and qualia (those aspects of a conscious experience which are directly knowable only via introspection, and thus only by the one undergoing the experience). And they contend that, given the mechanistic conception of matter taken for granted by modern philosophers (dualists and materialists alike), these features of the mind are necessarily immaterial.

Classical arguments for the immateriality of the mind, by which I mean the sort common within Western philosophy prior to Descartes and defended by the likes of Plato, Aristotle, and Aquinas, are very different. You won’t find the latter thinkers going on about either qualia or intentionality, because the very notions of qualia and intentionality, as usually understood, are artifacts of the modern mechanistic re-conception of the material world. “Qualia” are what you get when you deny that matter can have anything like the sensible qualities it seems to have in ordinary experience. “Intentionality” is what you get when you insist that the material world is devoid of anything like final causality, when you go on accordingly to relocate all meaning and purpose within the mind, and when you also go on in turn to characterize mental states as internal “representations” of an external reality. I have said a little bit about all of this in earlier posts, and it is a theme I explore in great detail in The Last Superstition.

For Plato, Aristotle, Aquinas, and other ancients and medievals, the main reason why the mind has to be immaterial concerns its affinity to its primary objects of knowledge, namely universals, which are themselves immaterial. When properly fleshed out and understood, this sort of argument is in my view decisive. Yet it has received very little attention from contemporary philosophers, partly, I think, because of their general ignorance of what the ancients and medievals thought, and partly because the logic of the mechanistic revolution inaugurated by Galileo, Descartes, Hobbes, Locke, et al. has pushed them into so cramped and narrow a conceptual space that they can hardly even conceive any alternative to it. The result is that when they do address the arguments of the ancients and medievals (concerning this subject or any other), they almost always distort them in the most grotesque fashion, anachronistically reading into them assumptions that make sense only if one takes for granted conceptions of matter, mind, causation, etc. that the older thinkers in question would have regarded as deeply mistaken and muddleheaded. (Thus is Aristotle made out to be a “functionalist” vis-à-vis the mind, Aquinas’s Fifth Way is read as if it were an anticipation of Paley’s feeble “design argument,” etc.)

In The Last Superstition, I explain at length why some form of realism about universals is rationally unavoidable. (Whether it is the Platonic form of realism, the Aristotelian one, or the Scholastic one that we should endorse is a separate matter irrelevant to present purposes.) I am not going to attempt to summarize that case here, but the examples to follow should suffice to give a sense of how an argument from the reality of universals to the immateriality of the mind might proceed. Readers wanting a fuller treatment should consult TLS.

Consider that when you think about triangularity, as you might when proving a geometrical theorem, it is necessarily perfect triangularity that you are contemplating, not some mere approximation of it. Triangularity as your intellect grasps it is entirely determinate or exact; for example, what you grasp is the notion of a closed plane figure with three perfectly straight sides, rather than that of something which may or may not have straight sides or which may or may not be closed. Of course, your mental image of a triangle might not be exact, but rather indeterminate and fuzzy. But to grasp something with the intellect is not the same as to form a mental image of it. For any mental image of a triangle is necessarily going to be of an isosceles triangle specifically, or of a scalene one, or an equilateral one; but the concept of triangularity that your intellect grasps applies to all triangles alike. Any mental image of a triangle is going to have certain features, such as a particular color, that are no part of the concept of triangularity in general. A mental image is something private and subjective, while the concept of triangularity is objective and grasped by many minds at once. And so forth. In general, to grasp a concept is simply not the same thing as having a mental image. (Again, see TLS for more details.)

Now the thought you are having about triangularity when you grasp it must be as determinate or exact as triangularity itself, otherwise it just wouldn’t be a thought about triangularity in the first place, but only a thought about some approximation of triangularity. Yet material things are never determinate or exact in this way. Any material triangle, for example, is always only ever an approximation of perfect triangularity (since it is bound to have sides that are less than perfectly straight, etc., even if this is undetectable to the naked eye). And in general, material symbols and representations are inherently always to some extent vague, ambiguous, or otherwise inexact, susceptible of various alternative interpretations. It follows, then, that any thought you might have about triangularity is not something material; in particular, it is not some process occurring in the brain. And what goes for triangularity goes for any thought that involves the grasp of a universal, since universals in general (or at least very many of them, in case someone should wish to dispute this) are determinate and exact in a way material objects and processes cannot be.

As James F. Ross has argued, some of the best-known arguments of twentieth-century analytic philosophy reinforce this judgment. For instance, Quine’s arguments for the indeterminacy of translation and Kripke’s argument regarding “quaddition” show that there is in principle nothing in the facts about human behavior or physiology, or in any other physicalistically “respectable” set of facts, that can determine (say) whether by “gavagai” I mean “rabbit” or “undetached rabbit part,” or whether I am doing addition rather than “quaddition.” Indeed, these arguments show that this same indeterminacy afflicts everything I say or do. Yet it is simply false that everything I say or do is indeterminate in this way. For example, should I deploy modus ponens in defending a Quine- or Kripke-style argument, what I will be deploying is indeed modus ponens and not some mere approximation of modus ponens; certainly it had better be modus ponens and not some mere approximation, otherwise my arguments would all be invalid. Nor will it do to suggest that maybe all my arguments really are invalid, for even to deny that I ever really use modus ponens but only ever approximate it requires that I first grasp determinately what modus ponens is before judging that I never really engage in it. Similarly, if someone wanted to deny that we ever really grasp perfect triangularity, he would first have to grasp it himself before going on to judge (obviously falsely, in that case) that it is something we never grasp.

So, there is no coherent sense to be made of the suggestion that all of our thoughts are indeterminate. But if at least some of them are determinate, and no physical process or set of physical facts is ever determinate, it follows that at least some of our thoughts are not physical. (Ross’s argument, by the way, is elegantly developed in his article “Immaterial Aspects of Thought,” which appeared in the Journal of Philosophy in 1992. A later version of this article is available at his website, in the form of a chapter of his book manuscript Hidden Necessities.)

That is one way an argument from realism about universals to the immateriality of the mind can be developed. There are other ways too, which I will summarize in future posts.

Whatever one thinks of arguments like this, it is important to understand that (like the other arguments I’ve presented in this series) they are not the sort that might be undermined by the findings of neuroscience, or any other empirical science for that matter. They are not “soul of the gaps” arguments which purport to give a quasi-scientific explanation of some psychological phenomenon that we simply haven’t got enough empirical data to explain in a materialistic way. Rather, they purport to show that it is in principle impossible, conceptually impossible, for the intellect to be accounted for in a materialistic way. If such arguments work at all, they establish conclusively that the intellect could no more be identified with processes in the brain than two and two could make five. If they are mistaken, they would be mistaken in the way one might make a mistake in attempting to carry out a geometrical proof, and not by virtue of having failed to take account of this or that finding of brain research.


  1. Hello Professor Feser. Thank you for providing another thoughtful article. I've been interested in your discussions on these subjects ever since I read "The Philosophy of Mind: A Short Introduction." I have not read "The Last Superstition" yet, but I do have it on order, so excuse me if I ask anything that's already been addressed by the book.

    It seems the central argument in the later part of this article is that the concept of universals are not material, therefore thoughts about the concept of universals are not material. Is my understanding here correct? Would not the materialist reply that this is indeed a "soul of the gaps" argument? i.e. We simply don't know how abstract concepts are formed in the brain yet. However, we are well on our way to showing how other types of thoughts are formed. Therefore it's reasonable to assume that abstract thoughts will be eventually discovered in the same way?

  2. Ed

    This is a great article and I will certainly get my hands on your book.

    What do you think of the work of Saul Kripke and Hillary Putnam on definitions and its relations to philosophy of mind? Does it lend credence to the Aquinas definition of essential essences?

  3. Hello Chen-song,

    No, the point is that an abstract concept could not, even in theory, be material, given that concepts are determinate and material things are indeterminate. So to suggest that we'll eventually "discover" that concepts are properties of the brain is like saying we might someday "discover" that 2 + 2 = 5.

    Hello Damien,

    Thanks. Re: Kripke and Putnam, while their revival of the idea of essences is a welcome development, from an Aristotelian-Thomistic point of view it is still inadequate. The differences between Aristotelian essentialism and contemporay Kripke-Putnam essentialism have been discussed by David Oderberg in his book Real Essentialism and his article "How to Win Essence Back from Essentialists," and by Gyula Klima in his article "Contemporary 'Essentialism' vs. Aristotelian Essentialism." Oderberg's and Klima's articles are available on their respective websites, which you'll find links to here on my blog under "Recommended philosophers' websites."

  4. Thank you for the reply. So the idea here is that thoughts about abstract concepts contain abstract concepts, and so those thoughts are not reducible to material origins? I just wanted to get the idea clear here.

    Also, I found a rather disturbing development in this New Scientist article:

    See the confusion of any objection to materialism with ID/creationism displayed here. It could be that in the future, any non-materialist might get tainted with the "creationist" brush over a debate that doesn't even concern science at all.

  5. Prof Feser,
    I like to observe, in connection, with a previous post actually, that CS Lewis held thinking to be an instance of Supernature and that mind does move atoms about.
    (Miracles). I had thought this picture to be unsatisfactory and now I feel I have got a better picture of soul-body relation from your post.

  6. Materialism gets itself into a hole in the foundational problems of quantum mechanics what with conscious observers required to collapse wavefunctions and associated paradoxes. The very matter seems to be quite immaterial.
    The existing interpretations of quantum mechanics all suffer from one problem or another. The current favorite though seems to be Many-World interpretation.

    I wonder if your viewpoint based upon Aristotle could provide an alternative
    interpretation of quantum mechanics. It would be quite a sensation and also very muh needed as every wonderful theory needs applications

  7. While I respect the metaphysical realist position to some extent--a better argument for immaterialism of some sort than intentionality, I would aver-- it's again a matter of addressing competing claims, and not merely saying it's impossible for empiricists, nominalists, materialists, and the rest to account for universals (or apparent universals), logical/mathematical entities, taxonomies, "Justice", beauty etc.

    I don't pretend to be a master of platonic or Aristotelian metaphysics, but I strongly suspect that taxonomy was worked out over centuries: the noun "mammal" describes a class of warm-blooded, hairy vertebrates (attributes, as y'all say) which exist in the real, observable world. However quotidian or even vulgar that seems, that's a universal (at least on earth). The terms/nomenclature could be changed, but the class is out there in some sense.

    Cardinal numbers, triangles, functions, modus ponens, etc. might seem like a slightly different problem (and it is), but I believe that the class of triangles are more like Mammalia--abstracted from experience--than it is, well, the mind of JHVH (or Plato). Blind people would not likely have developed geometry (or physics, if not mathematics as a whole), regardless of what a Kant or Plato insists upon.

    Again, it's a matter of the lack of knowledge of learning mechanisms: what seemed mysterious (or knowledge dependent on an immortal soul) to Aristotle's students or Aquinas is not so mysterious now, and in a few centuries the learning process associated with mathematical knowledge will probably be neurologically mapped out. Not really so sublime, but then neither is human history......

  8. Isn't this an example of the content fallacy that Pasnau has shown Aquinas to fall into?

    Just because we are thinking of something red doesn't mean our thoughts must be red. Likewise, just because we are thinking of something immaterial doesn't mean our thoughts must be immaterial.

  9. That isn't the argument, and there is no "content fallacy" -- one of these days I'm going to write up a reply to Pasnau. Briefly, though, the claim isn't "The objects of thought are immaterial, so thoughts are immaterial," which would of course be fallacious. The argument is rather "The objects of thought have property X (e.g. determinacy), which makes them immaterial; and since thoughts too have this property, they also are immaterial." No fallacy.

  10. I have a question. You say the following:

    For any mental image of a triangle is necessarily going to be of an isosceles triangle specifically, or of a scalene one, or an equilateral one; but the concept of triangularity that your intellect grasps applies to all triangles alike.

    But doesn't that also hold true for a material triangle? That is a material triangle is not an approximation of triangularity, because no single triangle is triangularity, even if it were a perfect material triangle.

    I think to argue that triangularity can't be material because all material triangles are imperfect is a flawed argument. Even if a material triangle was perfect, it still wouldn't be triangularity.

    So I don't think argument argues that triangularity can't be material.

    Am I misunderstanding something?

  11. I was led to this post right after reading Freddoso's reference to it in a footnote to his updated, revised (2012) paper. The note reads:

    "Edward Feser helpfully reviews various of these arguments in a blog entry entitled “Some brief arguments for dualism, part IV” ( and in the three other parts linked at the beginning of that entry. [...] Unlike Feser, I am very uneasy describing St. Thomas’s position as a form of dualism — even ‘hylemorphic dualism’ — since it is precisely the unity of the human being that St. Thomas wants to emphasize over against Plato’s position, which (as he interprets it) posits many substantial forms in the human composite. (The term ‘hylemorphic dualism’ originates, I believe, with David Oderberg in Real Essentialism (New York: Routledge, 2007).) This is largely a verbal disagreement, but I for one resist making Thomistic philosophical anthropology conform to what I believe to be the illegitimate contemporary taxonomy of ‘solutions’ to the alleged ‘mind-body problem’, according to which each solution is either a type of materialism or a type of dualism."

    - A. Freddoso, 2012. "Oh, My Soul, There's Animals and Animals..."

    I remember reading Orderberg and thinking to myself: "very interesting.. hmm.. right on point... hmmm... hylemorphic DUALISM? what?" I've always thought it is a rather infelicitous way of characterizing Aristotelian-Thomistic hylemorphism. Freddoso agrees with me! :)

  12. OK, I realize I'm a few years late with this comment, but: Cannot these abstract, exact, determinate concepts, like triangularity, or addition, or whatever, also be coded into a computer program? And if they can, does that make the computer program immaterial too?

  13. The computer program is programmed by us to produce certain symbols as outputs when certain symbols are given as inputs. Those symbols themselves, as well as the algorithms that produce them, have no meaning apart from an interpreting mind.

    The computer program is material. The programming and interpretation of the program, however, is done by minds, which must in principle be immaterial.

  14. @ John,

    "I think to argue that triangularity can't be material because all material triangles are imperfect is a flawed argument."

    But that is not the argument. It wouldn't matter if this or that material triangle actually had, e.g., perfectly straight sides; it would still be a triangle of one and only one kind (i.e. either scalene, isosceles or equilateral). It would also have other features that were accidental limits: e.g., it would be of such-and-such a size; whereas, triangles can be of any size, big or small. But any material triangle is thus going to be limited; whereas, the concept of triangularity is not so limited but includes all possible triangles. No material triangle could at the same time be all possible triangles (indeed this would involve impossible contradictions) simply and exactly because it is material.

    Moreover, any material triangle is also, e.g., subject to change because matter can always at least potentially change and take on a different form; whereas, triangularity does not change. This or that triangle could be made of a composite or patchwork of material or a single material but also potentially many other kinds of material; and each kind of material is in its turn potentially a different material.

  15. While reading The Last Superstition and Philosophy of mind, I found myself wondering about something. It seems that much time is spent discussing mind vs matter. And a strong (irrefutable, in my opinion) case is made for mind != matter. But what about energy? Energy is just as mysterious and immaterial and is just as similarly attached to matter. Why couldn't mind be energy? Or why, at least, does this not get discussed?