Jackson on Popper on materialism

While we’re on the subject of mind-body interaction, let’s take a look at Frank Jackson’s article on Karl Popper’s philosophy of mind in the new Cambridge Companion to Popper, edited by Jeremy Shearmur and Geoffrey Stokes.  Popper was a dualist of sorts, and Jackson’s focus is on the role Popper’s “World 3” concept and the issue of causal interaction played in his critique of materialism.

Post-intentional depression

A reader asks me to comment on novelist Scott Bakker’s recent Scientia Salon article “Back to Square One: toward a post-intentional future.”  “Intentional” is a reference to intentionality, the philosopher’s technical term for the meaningfulness or “aboutness” of our thoughts -- the way they are “directed toward,” “point to,” or are about something.  A “post-intentional” future is one in which we’ve given up trying to explain intentionality in scientific terms and instead abandon it altogether in favor of radically re-describing human nature exclusively in terms drawn from neuroscience, physics, chemistry, and the like.  In short, it is a future in which we embrace the eliminative materialist position associated with philosophers like Alex Rosenberg and Paul and Patricia Churchland.

Do machines compute functions?

Robert Oerter has now replied to my most recent post about his criticisms of James Ross’s argument for the immateriality of the intellect.  Let me begin my rejoinder with a parable.  Suppose you presented someone with the argument: All men are mortal; Socrates is a man; therefore, Socrates is mortal.  He says he is unconvinced.  Puzzled, you ask him why.  He replies that he is surprised that you think Socrates is mortal, given that you believe in the immortality of the soul.  He adds that all you’ve done in any case is to make an epistemological point about what we know about Socrates, and not really given any reason to think that Socrates is mortal.  For though the conclusion does, he concedes, follow from the premises, and the premises are supported by the evidence, maybe for all we know there is still somehow more to men than what the premises tell us.

Churchland on dualism, Part V

Paul Churchland has just published a third edition of Matter and Consciousness, his widely used introductory textbook on the philosophy of mind.  The blog Philosophy of Brains has posted a symposium on the book, with contributions from Amy Kind, William Ramsey, and Pete Mandik.  Prof. Kind, who deals with Churchland’s discussion of dualism, is kind to him indeed -- a little too kind, as it happens.  Longtime readers will recall a series of posts I did several years ago on the previous edition of Churchland’s book, in which I showed how extremely superficial, misleading, and frankly incompetent is its treatment of dualism.  Prof. Kind commends Churchland’s “clear writing style and incisive argumentation” as “a model for us all.”  While I agree with her about the clarity of Churchland’s style, I cannot concur with her judgment of the quality of the book’s argumentation, for at least with respect to dualism, this new edition is as bad as the old. 

Reading Rosenberg, Part VIII

And now, dear reader, our critical look at Alex Rosenberg’s The Atheist’s Guide to Reality brings us to the pseudoscience du jour.  Wittgenstein famously said that “in psychology there are experimental methods and conceptual confusion” (Philosophical Investigations, II, xiv, p. 232).  He might as well have been talking about contemporary neuroscience -- or, more precisely, about how neuroscience becomes distorted in the hands of those rich in empirical data but poor in philosophical understanding.  Every week seems to bring some new sensationalistic claim to the effect that neuroscience has “shown” this or that -- that free will is an illusion, or that mindreading is possible, or that consciousness plays no role in human action -- supported by arguments notable only for the crudeness of the fallacies they commit.  

Tyler Burge has given the label “neurobabble” to this modern intellectual pathology, and Raymond Tallis calls it “neurotrash,” born of “neuromania.”  I’ve had reason to comment on it in earlier posts (here and here) and an extreme manifestation of the disease is criticized in the last chapter of The Last Superstition.  M. R. Bennett and P. M. S. Hacker subject neurobabble to detailed and devastating criticism in their book Philosophical Foundations of Neuroscience, and Tallis does a bit of housecleaning of his own in Aping Mankind.  Neurobabble is a key ingredient in Rosenberg’s scientism.  Like so many other contemporary secularists, he has got the brain absolutely on the brain, and maintains that modern neuroscience vindicates some of his more outrageous metaphysical claims.  In particular, he thinks that so-called “blindsight” phenomena establish that consciousness is irrelevant to our actions, and that neuroscientist Benjamin Libet’s experiments cast doubt on free will.  (Jerry Coyne, in a recent article, has made similar claims about free will.  What I’ll say about Rosenberg applies to Coyne as well.)

Mind-body problem roundup

For readers who might be interested, I thought it would be useful to gather together in one place links to various posts on the mind-body problem and other issues in the philosophy of mind.  Like much of what you’ll find on this blog, these posts develop and apply ideas and arguments stated more fully in my various books and articles.  Naturally, I address various issues in the philosophy of mind at length in my book Philosophy of Mind, of which you can find a detailed table of contents here.  (The cover illustration by Andrzej Klimowski you see to the left is from the first edition.)  You will find my most recent and detailed exposition of the Aristotelian-Thomistic (A-T) approach to issues in the philosophy of mind in chapter 4 of Aquinas.  There is a lot of material on the mind-body problem to be found in The Last Superstition, especially in various sections of the last three chapters.  And there is also relevant material to be found in Locke, in the chapter I contributed to my edited volume The Cambridge Companion to Hayek, and in various academic articles.

Scientism roundup

In several recent posts we have dealt at least indirectly with scientism, the view that the only real knowledge is scientific knowledge.  Scientism is an illusion, a bizarre fantasy that makes of science something it can never be.  Seemingly the paradigm of rationality, it is in fact incoherent, incapable in principle of being defended in a way consistent with its own epistemological scruples.  It should go without saying that this in no way entails any criticism of science itself.  For a man to acknowledge that there are many beautiful women in the world does not entail that he doesn’t think his own wife or girlfriend is beautiful.  Similarly, to say that there are entirely rational and objective sources of knowledge other than science does not commit one to denying that science is a source of knowledge.  Those who cannot see this are doubly deluded – like a vain and paranoid wife or girlfriend who thinks all women are far less attractive than she is and regards any suggestion to the contrary as a denial of her own beauty.  Worse, like an already beautiful woman whose vanity leads her to destroy her beauty in the attempt to enhance it through plastic surgery, scientism threatens to distort and corrupt science precisely by exaggerating its significance.

Against “neurobabble”

Every written token of the English word “soup” is made up of marks which look at least vaguely like “s,” “o,” “u,” and “p.”  Of course, it doesn’t follow that the word “soup” is identical to any collection of such marks, or that its properties supervene on the material properties of such marks, or that it can be explained entirely in terms of the material properties of such marks.  Everyone who considers the matter knows this.

To borrow an example from psychologist Jerome Kagan, “as a viewer slowly approaches Claude Monet's painting of the Seine at dawn there comes a moment when the scene dissolves into tiny patches of color.”  But it doesn’t follow that its status and qualities as a painting reduce to, supervene upon, or can be explained entirely in terms of the material properties of the color patches.  Everyone who considers the matter knows this too.

Somehow, though, when neuroscientists discover some neural correlate of this or that mental event or process, a certain kind of materialist concludes that the mind’s identity with, or supervenience upon, or reducibility to, or complete explanation in terms of neural processes is all but a done deal, and that the reservations of non-materialists are just so much intellectually dishonest bad faith.  In a recent online op-ed piece for The New York Times, and in an apt phrase, philosopher of mind Tyler Burge criticizes this tendency as “neurobabble,” which produces only “the illusion of understanding.”  For it is as fallacious as any parallel argument about words or paintings would be.

Popper’s World 3

The Self and Its Brain: An Argument for Interactionism, a long exchange between philosopher Karl Popper and neuroscientist John Eccles, is among the most significant 20th century defenses of mind-body dualism. I do not agree with every aspect of their approach, but the book is filled with interesting things and deserves more attention than it has received in contemporary philosophy of mind.

Popper famously distinguished between three “worlds” or levels of reality. (Though whether “levels” of reality is the right gloss on Popper’s theory is not clear. “Kinds”? “Aspects”?) World 1 is the world of physical entities and states – tables, chairs, rocks, trees, fundamental particles and forces, human bodies and behavior, and so forth. World 2 is the world of thoughts, sensations, and mental phenomena in general. World 3 is the world of scientific and philosophical theories, arguments, stories, social institutions, works of art and the like. World 3 differs from World 1 in that the entities comprising it are abstract; for example, though a theory or argument might be embodied in a particular book (a World 1 object) it does not depend for its reality on the existence of that book, or on any book or World 1 object at all. We could still consider the Pythagorean theorem, know it to be true, prove it, etc. even if every geometry textbook that had ever existed were destroyed. World 3 differs from World 2 in being objective or public, whereas World 2 is subjective or private. Your thoughts and experiences are directly knowable only to you, but World 3 objects are equally accessible to everyone.

The objectivity or “autonomy” of such World 3 objects as theories and arguments is especially evident in Popper’s view from the fact that they have logical relations – and in particular, unforeseen implications and unnoticed inconsistencies – that may not be noticed until well after we first consider them, but which were evidently there all the time waiting to be discovered. Naturally, he takes mathematics to illustrate the point vividly, but it is in his view no less evident from empirical scientific theories. The clearest mark of the reality of all three worlds is in Popper’s judgment the fact that World 3 has a causal influence on World 1, and does so only via World 2. For example, the scientific theories which entailed the possibility of nuclear weapons have had an obvious impact on the material world – they have resulted in various nuclear tests, in the destruction of Hiroshima and Nagasaki, and so forth – but only because scientists carried out the mental activity of working out the implications of the theories and applying them.

Popper’s World 3 is often compared to Plato’s realm of the Forms, and Popper himself acknowledges that there are similarities. But he also emphasizes the significant differences between his view and Plato’s, not the least of which is that he takes World 3, despite its objectivity or autonomy, to be something “man-made,” its objects in the strict sense being what the human mind “abstracts” from their World 1 embodiment. Though Popper does not take note of the fact or develop the theme in much detail, this is clearly reminiscent of an Aristotelian or “moderate realist” approach to the traditional problem of universals, as distinct from the “extreme realism” of Platonism. (See here and here for a useful short account of the traditional Aristotelian-Thomistic-Scholastic approach to the issue and its significance.)

In other ways too Popper’s views as expressed in The Self and Its Brain overlap to some extent with Aristotelian ones. The emphasis on abstract thought – and thus on what is unique to human beings – as what is of greatest interest in the debate over dualism is very much in line with the classical Platonic-Aristotelian-Scholastic approach to this subject, which is quite different from the contemporary obsession with “qualia” and the like. There is also Popper’s acknowledgement of the reality of “downward causation” in physical systems and his consequent rejection of physicalistic reductionism even where non-mental phenomena are concerned. And there is his affirmation of the existence of objective “propensities” in nature, which (possibly) hints at something like the Aristotelian notion of potencies. (Though these last two themes take us beyond the World 3 thesis itself.)

On the other hand, there are some decidedly un-Aristotelian themes in Popper as well. There is, for instance, his denial of substance in favor of a “process” conception of the material world; and there is his rejection of essentialism, which he seems to assume is inherently Platonistic and committed to an a priori or “armchair” methodology. (This is a serious misunderstanding, and a very common one, which we Aristotelian-Thomistic (A-T) types find it rather tiresome constantly to have to rebut. See Oderberg’s Real Essentialism for the most thorough rebuttal, and pp. 30-38 for a reply to Popper specifically.)

All the same, any Aristotelian must admire the non-ideological character of Popper’s approach to the mind-body problem. Unlike so many contemporary philosophers of mind, he does not fatuously pretend that a presumption in favor of materialism has somehow been established by modern science, or that dualism rests on “intuitions” or the like. He does not present the problem situation as if it were a matter of determining whether we ought to wedge the evidence of our ordinary experience into the Procrustean bed of naturalism or instead to lop it off entirely – as if these were the only alternatives worth taking seriously. Nor does he have any theological ax to grind; he deliberately avoids getting into the question of the soul’s immortality (and even expresses the view that he would prefer not to be immortal). He merely observes that reality clearly comprises at least the three sorts of thing in question and that any serious solution to the mind-body problem will simply have to accommodate this plain fact. As The Self and Its Brain shows, Popper is also much better informed about the actual history of the mind-body problem than contemporary naturalists tend to be. (As my series of posts on Paul Churchland indicated, many naturalists seem unfamiliar with anything other than the crudest caricatures of what non-naturalist philosophers of mind have actually said.)

In short, at least where the mind-body problem is concerned, Popper does not attack straw men and he respects Butler’s famous dictum that “Everything is what it is, and not another thing.” (I put to one side for present purposes Popper’s views in political philosophy and philosophy of science, contexts in which he is more open to criticism on these grounds.) He thereby stands acquitted of a charge John Searle raised in The Rediscovery of the Mind against his fellow contemporary philosophers of mind:

[W]e let our research methods dictate the subject matter, rather than the converse. Like the drunk who loses his car keys in the dark bushes but looks for them under the streetlight, "because the light is better here,” we try to find out how humans might resemble our computational models rather than trying to figure out how the conscious human mind actually works…

[W]e ought to stop saying things that are obviously false. The serious acceptance of this maxim might revolutionize the study of the mind. (p. 247)

Like Searle, Popper is in my estimation better as a critic than as a positive theorist. (I discussed an important anti-materialist argument of his in an earlier post.) Still, from an A-T point of view even his positive theorizing is closer to the mark than that of most other contemporary dualists.

Churchland on dualism, Part IV

Daniel Stoljar’s remarks on dualism, which I criticized in an earlier post, bring to mind some similar remarks made by Paul Churchland in response to Frank Jackson’s famous “knowledge argument” against physicalism. You’ll recall that Stoljar claimed that objections to a physicalist account of intentionality would apply no less to a dualist account. Churchland makes the same claim with respect to qualia – the introspectible features of a conscious experience, in virtue of which there is “something it is like” to have that experience. (Stock examples of qualia would be the way pain feels, the way red looks, or the way coffee tastes and smells.)

Jackson’s argument goes roughly like this. Imagine that Mary, a master neuroscientist of the future, has lived her entire life in a black and white room, never having had any experience of colors. But she knows everything there is to know about the physical facts concerning the physics and physiology of color perception. Thus, though she’s never seen a red object herself, she knows exactly what happens in other people’s eyes and nervous systems when they see red, as well as all the relevant facts about light, surface reflectance properties of red objects, and so on. Eventually she leaves the room and sees a red object for the first time. Does she learn something new? Jackson says she clearly does – she learns what it’s like to see red. And that (so the argument goes) suffices to refute physicalism. For physicalism claims that to know all the physical facts about human beings is to know all the facts about them, period. But though Mary knew all the relevant physical facts about color perception prior to her release from the room, she didn’t know all the facts, because she learned something new upon her release. Hence there is more to human nature than is captured by a description of the physical facts. In particular, facts about qualia (such as the facts about what it’s like to see red) are additional facts, beyond the physical facts.

I will have more to say about the knowledge argument – and in particular about Jackson’s later change of heart about it – in a future post. For now let’s consider Churchland’s objection, which he first stated in his paper “Reduction, Qualia, and the Direct Introspection of Brain States” and repeated in his later paper “Knowing Qualia: A Reply to Jackson.” (Both papers are reprinted in Churchland’s book A Neurocomputational Perspective, which is the source of the quotes below.) In the course of making several other criticisms of Jackson, Churchland says that if the knowledge argument were sound, it would refute substance dualism for the same reasons it would refute materialism. For we need only run the argument by imagining instead that Mary is a master “ectoplasmologist” with knowledge of the “hidden constitution and nomic intricacies” of ectoplasm, and in particular of “everything there is to know about the ectoplasmic processes underlying vision” (“Reduction, Qualia, and the Direct Introspection of Brain States,” p. 63). Since Mary would learn something new upon leaving the room despite knowing everything there is to know about ectoplasm, this parallel argument “would ‘show’ that there are some aspects of consciousness that must forever escape the ectoplasmic story” (“Knowing Qualia,” p. 72, emphasis in the original).

But Churchland is just making the same mistake we saw Stoljar make. What philosophical dualist ever said anything about “ectoplasmic processes,” or about the “hidden constitution” or “nomic intricacies” of an immaterial substance? Even apart from the “ectoplasm” nonsense – which is, of course, just a rhetorical flourish intended to make dualism sound ridiculous before it is even given a hearing – Churchland’s description of dualism is a ludicrous caricature. He makes it sound as if the dualist were committed to the existence of an object which is just like a material object in having various parts arranged in a certain way so as to behave according to law-like regularities, only one made out of some ghostly kind of stuff rather than of matter. But that is precisely the opposite of what a Plato, an Aquinas, or a Descartes actually held. For them, as for philosophical dualists generally, the soul is necessarily something simple or non-composite, and thus without parts of either a material or a quasi-material sort. Hence it has no “hidden constitution” or “nomic intricacies” of the sort Churchland has in mind. It is not a kind of ghostly mechanism because it is not a “mechanism” at all. (True, Descartes was a mechanist, but only concerning the material world, not the mind.)

For the Cartesian dualist, who is Churchland’s immediate target, the essence of the soul is just to think, and thought is (on this view) essentially conscious. As Descartes says in a letter to Mersenne, “nothing can be in me, that is to say, in my mind, of which I am not conscious” (Descartes, Philosophical Letters, p. 90, emphasis in original), and as he writes in the replies to the Second Set of Objections, “thought is a word that covers everything that exists in us in such a way that we are immediately conscious of it” (Haldane and Ross, Philosophical Works of Descartes, vol. II, p. 52, emphasis in original). In the Fifth Set of Objections, Gassendi had complained that Descartes fails to provide an account of the “internal substance” of the mind, which would require something analogous to the “chemical investigation” by which we discover what unseen properties of wine determine its surface features (Cottingham, Stoothoff, and Murdoch, Philosophical Writings of Descartes, vol. II, p. 193). Descartes replied, in words that could have been directed at Churchland: “You want us, you say, to conduct ‘a kind of chemical investigation’ of the mind, as we would of wine. This is indeed worthy of you, O Flesh, and of all those who have only a very confused conception of everything, and so do not know the proper questions to ask about each thing” and (in response to another of Gassendi’s objections) that “your purpose was simply to show us what absurd and unjust quibbles can be thought up by those who are more anxious to attack a position than to understand it” (Ibid., pp. 248-49). For Descartes, your res cogitans isn’t something which, by virtue of some hidden internal constitution, generates your consciousness; your res cogitans just is your consciousness.

For that reason, there can be no “knowledge argument” against substance dualism parallel to Jackson’s argument against physicalism. If the Mary of Churchland’s alternate scenario does not know what it is like to experience red before leaving the room, then she just does not and cannot know everything there is to know about res cogitans, because experiencing red is nothing more than a mode of consciousness and (therefore) a mode of res cogitans. To know everything there is to know about a res cogitans would not involve knowing about its internal constitution, the causal relations holding between its parts, etc. (for it has none of these things) but would involve instead knowing every kind of conscious thought or experience it might have – including experiencing red. The “gap” between two kinds of fact that Jackson’s original argument points to does not have even a prima facie parallel in the substance dualist case. The physicalist has to acknowledge at least a conceptual difference between physical facts and facts about consciousness; the only question is whether there is also a metaphysical difference. But there is, according to the Cartesian dualist, not even a conceptual difference between facts about res cogitans and facts about consciousness. That’s Descartes’ whole point.

Whatever other objections the physicalist might raise against dualism, then, the tu quoque strategy employed by Churchland and many other contemporary materialists is simply incompetent. It rests on a fundamental misunderstanding of what the dualist means by an “immaterial substance.” Equally incompetent is any critique of dualism that treats it (as Churchland evidently does in “Knowing Qualia”) as a kind of quasi-scientific empirical theory – that is, as if it were “postulating” the existence of immaterial substance as the “best explanation” of mental phenomena among the various alternatives. As I noted in a previous post on Churchland, that is not at all what the most significant dualists in the history of philosophy were up to. Their arguments for dualism are intended instead as strict metaphysical demonstrations of the existence of the soul. One may or may not think the attempted demonstrations succeed, but one will not refute them unless one first understands what sort of argument they are intended to be. Dualists traditionally tend to regard metaphysical inquiry as an enterprise every bit as rational as, but distinct from and more fundamental than, empirical science. Committed as they often are to scientism, contemporary materialists would no doubt deny that there can be any such form of inquiry, but they cannot deploy this denial in an argument against dualism without begging the question.

Their unreflective scientism is no doubt one source of contemporary materialists’ systematic misunderstanding of dualism. Since they think all rational inquiry must be a kind of scientific inquiry, they tend to (mis)interpret the claims of dualists (as they often do the claims of theists) as if they were feeble exercises in empirical hypothesis formation. It seems to me that another source might be the enormous influence Gilbert Ryle’s book The Concept of Mind had on mid-twentieth century philosophy. For Ryle there characterized Descartes’ position, absurdly, as a “para-mechanical hypothesis” on which minds are “rather like machines but also considerably different from them,” being “spectral machines” that are “complex organized unit[s]” which run on “counterpart” principles to those of physical substances, “made of a different sort of stuff and with a different sort of structure” which might be thought of “not [as] bits of clockwork [but rather] just bits of not-clockwork” and where the “bits” are arranged into a “field of causes and effects” (pp. 18-20). It is as if Churchland’s generation of materialists got their “knowledge” of what dualists believe from reading Ryle, and the generations since have gotten their “knowledge” from reading people like Churchland.

In any event, the materialist who characterizes the soul in terms of “ectoplasm” is like the atheist who compares the God of classical theism to the “Flying Spaghetti Monster” or thinks that the cosmological argument starts with the premise that “Everything has a cause…” Not to put too fine a point on it, neither one knows what the hell he is talking about or has any business opening his mouth on the subjects in question.

Stoljar on intentionality

Daniel Stoljar’s new book Physicalism is a very useful overview of its subject. However, its brief treatment of intentionality (and of some other topics too) evinces a deep misunderstanding of dualism, a misunderstanding that seems to be very common in contemporary philosophy of mind.

Stoljar begins his discussion with the following characterization of intentionality:

The intentionality of a mental state is its aboutness. When I think of Vienna or believe that the computer is on the desk or fear that the planet will get hotter, I instantiate mental states which are in a hard to define sense about Vienna, or the computer on the desk or planet Earth. The idea is that mental states (and speech acts) have a property rather like signs, sentences, and gestures; that is, they are about or represent things other than themselves. (p. 200)

So far so good; at least, that is an accurate characterization of what modern philosophers, whether physicalists, dualists, or idealists, tend to mean by “intentionality.” (Whether they are right to think of it this way is a question I will return to later.) Stoljar then suggests that the reason intentionality is philosophically problematic is that it is supposed to involve a relation that might hold between a thinker and something else, and yet lacks three key features one would expect such a relation to have. First, if I bear a relation to something else, one would expect that that something else exists; and yet I can think about something that does not exist (e.g. Valhalla). Second, if I bear a relation to something else, one would expect that there is some particular thing I bear it to; but I can think about a man without there being some man in particular I am thinking of. Third, if I bear a relation to some thing A and A = B, then one would expect that I thereby bear that relation to B; but if I am thinking about Vienna, then even though Vienna is the birthplace of Schubert, it doesn’t follow that I am thinking about the birthplace of Schubert, about whom I may know nothing. (To use the technical jargon, ascriptions of intentional mental states are often non-extensional or intensional, insofar as we cannot always substitute co-referring expressions salve veritate; that is to say, intentionality-with-a-t is often – though, it is important to note, not always – associated with intensionality-with-an-s.)

Now, Stoljar acknowledges that these features of intentionality are philosophically puzzling. But he claims that they pose no special difficulty for physicalism. In particular, they give us no reason to favor dualism over physicalism, for they are as problematic on the former view as on the latter. Says Stoljar: “[S]uppose classical dualism is true and I am some sort of complex of an ordinary physical object and soul; it is still impossible for me to stand in a relation to things that don’t exist! In sum, the paradoxes of intentionality will remain whether physicalism is true or not, hence they do not concern physicalism.” (p. 201)

There are two problems with this. First, it does not get to the heart of the problem of intentionality. Second, it rests on a misunderstanding of dualism. Let’s take them in order.

Consider the following dialogue:

Policeman: Ma’am, some bad news, I’m afraid. Your son just robbed a liquor store. Caught him red-handed with the cash tucked in the glove compartment, along with a few bottles of Tanqueray, vermouth, and tipsy olives that he tossed in the back seat.

Mom: Oh dear. I suppose he’s in trouble for being under 21. Or was he speeding in the getaway car?

Policeman: Well, there is that, I guess. But here’s the main thing: He robbed a liquor store.

Stoljar reminds me a little bit of Mom. Yes, the “paradoxes of intentionality” that he calls attention to are important. But it is intentionality itself, and not the “paradoxes,” that is of the greatest interest. Even if the objects I thought about always existed, or were always particular, or never generated non-extensional contexts – that is to say, even if intentionality exhibited none of the “paradoxical” features in question – the “aboutness” of my thoughts would remain. And it is that “aboutness” that the dualist takes to pose the chief difficulty for physicalism.

There are at least two ways to see how – a commonsense way and a more technical way. The commonsense way is this. Consider the word “cup” as you might write it in ink. Now consider a set of splotches that forms after your ink bottle leaks overnight, among which there are three right next to each other that by chance look vaguely like this: CUP. The set of splotches looks like the word, but it isn’t. The word has meaning, the splotches do not. But this has nothing to do with the physical properties of either. The ink is the same in both cases, as are the shapes. We can even imagine a case where your penmanship is bad enough and/or the splotches are distinct enough that their appearance is indistinguishable from the word “cup” that you’ve written. In general, it is not the intrinsic physical properties of letters, words, and sentences, whether written or spoken, that give them the meaning they have. Rather, their meaning derives from the conventions established by language users. It is an accident of history that the sequence of shapes cup has meaning and the sequence of shapes - ( ^ does not. Intrinsically, the first sequence is as meaningless as the second. But what is true of ink splotches and sounds seems no less true of all other physical phenomena. They all seem obviously devoid of meaning until someone decides to use them to convey meaning. As John Searle puts it, words, sentences, and the like, considered as material objects, have only “derived intentionality.” We are able to impart meaning to them by virtue of having thoughts with “original intentionality” – your thought about a cup represents or means cup without anyone having to form a convention of using it to mean that. But if neural processes are as devoid of original intentionality as ink marks, sounds, and the like, then it is hard to see how thoughts could be identified with neural processes, or claimed to supervene upon them. And the same is true of any other purported physicalistic basis for mental phenomena.

Now, there are various things a physicalist might want to say in response to this, but the point is that the problem intentionality is claimed to pose for physicalism here can obviously be stated in a way that makes no reference to the “paradoxes of intentionality.” If the commonsense point just made constitutes a difficulty for physicalism, it would do so even if the paradoxes in question did not exist.

The more technical way of making the point is to emphasize that the conception of “the physical” that physicalism typically presupposes is a mechanistic one – that is to say, one which (as I have discussed ad nauseam, e.g. here) takes matter to be devoid of any immanent or intrinsic final causality or teleology of the sort affirmed by the Aristotelian-Scholastic tradition the early moderns sought to overthrow. For the Scholastics, efficient causes in the natural order inherently “point to” or are “directed at” their effects, and in sweeping aside immanent final causality the moderns rejected the claim that any natural phenomenon inherently and irreducibly “points to” or is “directed at” anything at all. Intrinsically, the natural world is for them comprised instead of “nothing but” meaningless, purposeless particles in motion or the like. (Descartes, Locke, Boyle, Newton, and other early mechanists did of course think of ends or goals being imposed on the world by God, but precisely because they were mechanists opposed to Aristotelianism and Scholasticism, they saw the resulting purposes or meanings as extrinsic to the world rather than inherent. See the great many posts on this theme that I’ve written over the last several months, as well as the discussions in The Last Superstition and Aquinas.)

Now, if intentionality involves something “pointing to” or being “directed at” or “about” something beyond itself, and the mechanistic conception of matter underlying physicalism holds that there is no such thing in nature as something inherently and irreducibly being “directed at” or “pointing to” something else, then it seems at the very least difficult to see how intentionality could possibly be something material or physical. I had reason to make this point in my recent post on Chomsky. But though Stoljar quotes the same passage from Jerry Fodor that I cited there, he does not see (as Fodor does, though Fodor does not make explicit reference to the anti-Aristotelian mechanistic revolution) that it is the moderns’ own conception of matter, rather than the “paradoxes of intentionality,” that generates the difficulty.

Again, the point is not that the physicalist might not have a good response to points like the ones I’ve been making – I don’t think so, but that’s another issue. The point is rather that it misses the point to address the problem of intentionality as if the paradoxes Stoljar calls attention to were at the heart of it, and as if it had nothing to do with the nature of “the physical.” Both the commonsense point and the technical point (as I have called them) show that the problem has very much to do with the nature of the physical, and nothing essentially to do with the paradoxes.

But how, the physicalist might still ask, does dualism fare any better? For as Stoljar suggests, wouldn’t any objection to a physicalist account of intentionality apply mutatis mutandis to any dualist alternative? Or as Clayton Littlejohn once objected in a remark in Victor Reppert's combox: “It seems like causal pathways in an immaterial substance would have the same content fixation problems as causal pathways in a physical substance.”

As I have said, this sort of objection seems increasingly common in contemporary philosophy of mind, but it is deeply confused. What dualist ever said anything about “causal pathways in an immaterial substance”? Stoljar and Littlejohn seem to think that what the dualist means by an immaterial substance or soul is something that is just like a material substance – and in particular, something with distinct and causally interrelated parts – only not material, but instead “made out of” some other kind of “stuff” (“ectoplasm” maybe). In short, a kind of ghostly machine, but a machine all the same. But that is precisely what dualists – whether of a Platonic, Thomistic, or Cartesian stripe – do not think the soul is. For dualists have typically held that the soul is simple or non-composite, and thus not “made out of” causally interrelated parts of any sort. That its activities cannot be modeled on those of a material substance is the whole point.

How should we think of it, then? For the Cartesian, the essence of the soul is thought, and that is the entirety of its essence. Descartes does not say: “Gee, it’s hard to see how intentionality could be explained in terms of causal relations between physical parts. I therefore postulate an immaterial substance with immaterial parts whose causal relations are capable of generating thought and intentionality.” That would imply that in addition to thought, a soul has of its nature the various parts in question and their characteristic interrelations. And that is just what Descartes denies. A Cartesian immaterial substance doesn’t generate thinking. It is thinking, and that is all that it is. For that reason, and contrary to what Stoljar assumes, the Cartesian conception of intentionality cannot possibly be open to the same objections raised against physicalism. To say “Maybe a Cartesian immaterial substance – that is to say, something which just is its activity of thinking – could, like a physical substance, exist in the absence of intentional mental states” is just incoherent. A physicalist might want to raise some other objection to the Cartesian view, but Stoljar’s tu quoque is not open to him.

Now, for the Thomistic or hylemorphic dualist, the soul is to be understood, not as pure thought, but rather as the substantial form of the living human body. And qua form, it is not a complete substance in the first place, much less a material or quasi-material one. (Talk of the soul as an “immaterial substance” is thus for the Thomist at least misleading, though he does hold that the soul subsists beyond the death of the body as an incomplete substance.) Here too, though, talk of interrelated quasi-material parts, “causal pathways,” and the like is completely out of place. But for the Thomist, the Cartesian’s talk of inner “representations” is out of place too; as I have discussed elsewhere (e.g. here and here) the “representationalist” conception of the mind is an essentially modern one that the ancients and medievals generally would have rejected. As a consequence, the ancients and medievals would reject too the essentially modern way of framing the issue of intentionality that I have, for the sake of argument, been following up to now in this post. For instance, if a broadly Aristotelian-Thomistic conception of nature is correct, then natural phenomena really do have intrinsic final causes after all, so that (for example) material efficient causes inherently “point beyond” themselves to their effects. It would follow that a thought’s “pointing beyond” itself cannot be what makes it immaterial; and indeed, that is not the sort of argument the ancients and medievals gave for the mind’s immateriality. (Nor did they argue from “qualia” – that too, as I have noted many times before, is a very modern sort of argument for dualism, and presupposes a mechanistic approach to nature.) The ancients and medievals focused instead on such features of our thoughts as their universality and determinacy, which they took to be essentially incompatible with thought’s having any material organ. (See here, here, chapter 4 of Aquinas and chapter 7 of Philosophy of Mind.)

But that is a gigantic topic of its own. Suffice it for present purposes to note that with respect to Thomistic dualism no less than the Cartesian version, contemporary physicalists would do well to try better to “know their enemy” before dismissing him.

[For more on this theme, see my posts on Paul Churchland and dualism, here, here, and here.]

Churchland on dualism, Part III

To conclude our look at Paul Churchland’s critical discussion of dualism in his textbook Matter and Consciousness, let’s consider the arguments he presents against dualism. There are four of them, and they can be summarized as follows:

1. The argument from Ockham’s razor: Postulating two basic kinds of substance, material and immaterial, needlessly complicates our ontology if mental phenomena can be adequately explained in terms of material substance alone. That they can be so explained is indicated by the next two arguments:

2. The argument from the explanatory impotence of dualism: Materialist explanations can appeal to the many details of the brain’s structure and function revealed by modern neuroscience, while dualists have yet to provide a comparable account of the structure and function of immaterial substance.

3. The argument from the neural dependence of all known mental phenomena: As both everyday experience and neuroscientific research show, reasoning, emotion, and consciousness are all very closely correlated with various processes in the brain, which is not what we would expect if these mental phenomena were associated with an immaterial substance.

4. The argument from evolutionary history: The evolutionary process that gave rise to the human species proceeded via purely material mechanisms from a purely material starting point, so that the end result must itself be purely material.

Churchland acknowledges that none of these arguments is by itself absolutely conclusive. But he does think the third one “comes close to being an outright refutation of (substance) dualism,” and he clearly believes that in tandem the arguments consign dualism to the dustbin for all practical purposes. No doubt most materialists would agree with him. But in fact these arguments have, I maintain, no force at all against dualism. None. Dualism may or may not in fact be true – obviously I think it is true, but that is another issue. The point is that, even if it were false, these arguments have no tendency to show that it is.

How can I say that? Easy. Keep in mind first of all that, as I have emphasized in the earlier posts in this series, the chief proponents of dualism historically have not defended their position as an “explanatory hypothesis” put forward as the “best explanation” of the “empirical data.” That just isn’t what they are up to, any more than geometers or logicians are. They are attempting instead to provide a strict demonstration of the immateriality of the mind, to show that it is metaphysically and conceptually impossible for the mind to be something material. Their attempts may or may not succeed – again, that is another question. But that is what they are trying to do, and thus it simply misses the point to evaluate their arguments the way one might evaluate an empirical hypothesis. When Andrew Wiles first claimed – correctly, as it turned out – to have proven Fermat’s Last Theorem, it would have been ridiculous to evaluate his purported proof by asking whether it best accounts for the empirical evidence, or is the “best explanation” among all the alternatives, or comports with Ockham’s razor. Anyone who asked such questions would simply be making a category mistake, and showing himself to be uninformed about the nature of mathematical reasoning. It is equally ridiculous, equally uninformed, equally a category mistake, to respond to Plato’s affinity argument, or Aristotle’s and Aquinas’s argument from the nature of knowledge, or Descartes’ clear and distinct perception argument, or the Cartesian-Leibnizian-Kantian unity of consciousness argument, or Swinburne’s or Hart’s modal arguments, or James Ross’s argument from the indeterminacy of the physical, by asking such questions. As with a purported mathematical demonstration, one can reasonably attempt to show that one or more of the premises of such metaphysical arguments are false, or that the conclusion does not follow. But doing so will not involve the sorts of considerations one might bring to bear on the evaluation of a hypothesis in chemistry or biology.

Of course, Churchland, committed as he is to a Quinean form of scientism, thinks that all good theories must in some sense be empirical scientific theories. He rejects the traditional conception of metaphysics as a rational field of study distinct from and more fundamental than physics, chemistry, biology, and the like, and would deny that there is any such thing as sound metaphysical reasoning that is not in some way a mere extension of empirical hypothesis formation. But he cannot simply assume all of this in the present context without begging the question, because this sort of scientism is precisely (part of) what the dualist denies. (As we have seen in earlier posts on naturalism, this kind of circular reasoning is absolutely rife in naturalist thinking.)

It is obvious, then, why Churchland’s first two arguments have no force, for they simply misconstrue the nature of the case for dualism. If any of the dualist arguments just mentioned works, then the immateriality of the mind will have been demonstrated, and asking “But do we really need to postulate immaterial substance?” or “How much can we really know about such substances?” would not be to the point. For we would not in that case be hypothetically “postulating” anything in the first place, but directly establishing its existence; and its existence will have been no less established even if we could not say much about its nature.

But this brings us to an additional problem with Churchland’s second argument, which further underlines just how embarrassingly uninformed he is about what dualists have actually said. In developing his “explanatory impotence” objection, Churchland complains that dualists have told us very little about the nature of “spiritual matter” or the “internal constitution of mind-stuff,” about the “nonmaterial elements that make it up” and the “laws that govern their behavior.” This is, for anyone familiar with the thought of a Plato, an Aquinas, a Descartes, or a Leibniz, simply cringe-making. The soul is not taken by these writers to be “made up” out of anything, precisely because it is metaphysically simple or non-composite. It is not a kind of “stuff,” it is not made out of “spiritual matter” (whatever that is), and it is not “constituted” out of “elements” which are related by “laws.” Nor is this some incidental or little-known aspect of their position – it is absolutely central to the traditional philosophical understanding of the soul. As is so often the case with naturalistic criticisms of dualism, theism, etc., Churchland’s argument is directed at a breathtakingly crude straw man.

This appalling ignorance of the actual views of dualists manifests itself again in Churchland’s third argument. Churchland himself admits that this argument has no effect against property dualism, since property dualism itself takes the brain to be the seat of mental phenomena. But he fails to see that it has no effect against the other main varieties of dualism either, given what they actually say about the relationship between the mind and the brain.

For starters, let’s take Aristotelian-Thomistic (A-T) hylemorphic dualism. The A-T view is that the intellect is immaterial, but that sensation and imagination are not. Hence it is no surprise at all that neuroscience has discovered various neural correlates of mental imagery and the varieties of perceptual experience. Moreover, A-T holds that though intellect is immaterial, its operation requires the presence of the images or “phantasms” of the imagination. Hence it is no surprise that neural damage can affect even the functioning of the intellect. Most importantly, the soul, of which intellect, sensation, and imagination are all powers, is not a complete substance in its own right in the first place, but rather the form of the body. The way intellectual and volitional activity relates to a particular human action is, accordingly, not to be understood on the model of billiard ball causation, but rather as the formal-cum-final causal side of a single event of which the relevant physiological processes are the material-cum-efficient causal side. That alterations to the body have mental consequences is thus no more surprising than the fact that altering the chalk marks that make up a triangle drawn on a chalkboard affects how well the marks instantiate the form of triangularity. It is important to emphasize that none of this involves any sort of retreat from some stronger form of dualism, as a way of accommodating the discoveries of contemporary neuroscience; it is what A-T has always said about the relationship between soul and body. There is absolutely nothing in modern neuroscience that need trouble the A-T hylemorphic dualist in the slightest.

What about the Cartesian dualist? Don’t the differences between Descartes’ views and those of his Scholastic predecessors make him vulnerable to the findings of neuroscience in a way the latter are not? No, they don’t. For one thing, and as I have noted in an earlier post, Descartes’ views on this subject were not in fact quite as different from those of his predecessors as is often supposed. For example, Descartes’ view appears to have been that it is the intellect, specifically, which is to be identified with the ego he thinks is capable of existing apart from the body. Sensations, emotions, and the like he regarded, not as purely mental phenomena, but rather as hybrid properties which can be predicated only of the soul-body composite, and not the soul alone. Hence even on Descartes’ view it is not at all surprising that neuroscience has discovered all sorts of correlations between various aspects of perceptual experience and various emotional states on the one hand, and various processes in the brain on the other.

Now what is true is that the Cartesian has a difficulty explaining mind-body interaction that the A-T view does not have, as I have discussed here and here. And the reason is that Descartes rejected the notion that the soul is the formal cause of the body. That is an enormously consequential difference between the two views. But it has nothing to do with the specific question about whether a dualist need be troubled by the discovery of detailed correlations between mental phenomena and neural phenomena, which is what is at issue in the argument of Churchland’s under consideration. In particular, even the Cartesian need not be troubled by the fact that intellectual activity too (and not just sensation, emotion, and the like) can be dramatically affected by changes to the brain.

Why not? For one thing, as Churchland himself admits, the Cartesian regards the brain as a “mediator” between the soul and the rest of the body, so that we should expect that damage to this mediator will prevent the intellect from receiving the information it derives from the body and from controlling bodily behavior as well as it normally would.

But there is a deeper consideration. Consider the following analogy: A typed, written, or spoken token of the word “bark,” considered merely as a material object, has all sorts of complex physical properties, and those physical properties are highly relevant to its status as a word, as a bearer of linguistic meaning. Alter the physical properties of the token too radically, and it can no longer convey the meaning it once did. For example, if the ink should smear, the sound be muffled, or the power source to a word processor be cut off, the word will disappear, or might at least become so distorted that it becomes unintelligible. It would be absurd, though, for someone to suggest that these facts lend any support whatsoever to the claim that a word token qua word token is exhausted by its physical properties. It clearly is not. It is, for example, indeterminate from the physical properties alone whether the “bark” in question is the bark of a dog or the bark of a tree. Indeed, since the fact that the relevant sounds and shapes are associated with a certain meaning is entirely contingent, an accident of the history of the English language, it is indeterminate from the physical properties alone whether the word has any meaning at all. In short, the physical properties are a necessary condition for any particular physical object’s counting as a word token, but they are not a sufficient condition. And piling up bits of physicochemical knowledge about word tokens cannot possibly change this fact in the slightest, for it is a conceptual point about the nature of words, not an empirical point about what the latest research in phonetics (or whatever) has turned up.

In the same way, the dualist claims to be making a conceptual point about the relationship between mind and body, one to which neuroscientific research, important and interesting as it is in itself, is irrelevant. The existence of such-and-such physiological phenomena may well be a necessary condition for the existence of intentional human actions, intelligible speech, and so forth, but it is not and cannot be a sufficient condition. And that remains true whether we are interpreting dualism in A-T terms or in Cartesian terms. A-T regards the soul as the formal cause of a single substance of which the matter of the body is the material cause. Cartesians regard mind and matter as two distinct substances. Either way, there is not, and in principle cannot be, anything distinctively mental in matter as such, any more than a word token, considered merely as an arrangement of ink marks or a pattern of sound waves, has any meaning on its own. Or at least, there cannot be if dualism is correct. No amount of neuroscientific evidence can undermine this judgment, because what is at issue is whether any purely material phenomena at all, neurological or otherwise, can in principle be mental.

“But doesn’t that make dualism unfalsifiable?” If “unfalsifiable” means “not subject to rational evaluation and criticism,” then no, of course it isn’t unfalsifiable. Metaphysical arguments, like mathematical arguments, are perfectly susceptible of rational analysis and refutation, even if, like mathematical arguments, such analysis does not involve the weighing of probabilities, the comparison of alternative empirical hypotheses, etc. If “unfalsifiable” means instead “not subject to refutation via empirical scientific research,” then yes, dualism is unfalsifiable in that sense. But so is mathematics, and yet that doesn’t detract from its status as a rational field of investigation. Again, if the materialist wants to insist that all rational inquiry must ultimately be a kind of empirical scientific inquiry, he is welcome to make the case, but he cannot simply assume the truth of scientism when criticizing the dualist, otherwise he will simply be begging the question.

And that brings us, finally, to the fourth of Churchland’s arguments, the argument from evolution. Here again we have an argument that is entirely without force, and the main reason should be obvious from what has just been said: Dualism is a metaphysical theory, not an empirical hypothesis, and thus it is not the sort of thing that could be refuted by empirical biological findings any more than by neuroscientific ones.

But there is more to be said. Churchland’s fourth argument is also question-begging. For whether Darwinian evolution – which is supposed to be a purely materialist theory – is in fact a complete explanation of human nature depends on whether human nature is entirely material. And of course, the dualist’s claim is precisely that human beings are not and cannot be purely material, in which case no purely materialist theory could possibly provide a complete explanation of human nature. Hence it is no good to merely to assert, as an argument against dualism, that Darwinism has already explained human nature in materialist terms. That simply assumes the falsity of dualism without proving it.

Nor is it any good to stamp one’s feet and insist that if Darwinism entails materialism, then we had all better be materialists. Because here’s a newsflash: If Darwinism entailed that 2 + 2 = 5, what that would show is, not that 2 + 2 = 5, but that Darwinism is false, or at least needs to be seriously modified. Similarly, if Darwinism really does entail materialism, but the arguments of an Aquinas, a Descartes, or a James Ross show that materialism is false, then so much the worse for Darwinism. It had better adapt itself to the metaphysical facts, or be selected out. Like so many other naturalists, Churchland waves the “evolution” talisman as if it sufficed to shut off all debate, assuring us that in light of Darwinism we “are creatures of matter” and “should learn to live with that fact.” But this is sheer, question-begging bluff, not serious philosophical argument.

We have seen, then, over the course of these three posts, that Churchland’s treatment of dualism in Matter and Consciousness, though purporting to be a balanced summary, is in fact almost completely worthless both as a guide to what dualists have actually said and as a critique of dualism. And this is a textbook! And a widely used one, which has long been in print – it was one of the books I was taught out of as an undergraduate, and (I am ashamed to say) as a teacher I once used it myself. It took me many years to see just how bad it is. Most students who have read it probably have no idea, and never will.

But that’s how bad ideas spread: By ignorance and intellectual dishonesty smugly masquerading as expertise. Here, as with the debate over theism, the naturalistic skeptic can maintain the illusion of rational superiority only to the extent that he and his readers remain ignorant of what the great thinkers of the past have actually said. For to paraphrase Cardinal Newman, to be deep in history is to cease to be a naturalist.

Churchland on dualism, Part II

Let’s continue our look at Paul Churchland’s critical discussion of dualism in his textbook Matter and Consciousness. I have noted that while Churchland neglects even to mention the most important arguments for dualism and devotes space to arguments that dualist philosophers themselves don’t actually put much stock in, he does at least discuss two arguments that many such philosophers do think important: the argument from introspection and the argument from irreducibility.

As Churchland summarizes the argument from introspection, it states that the thoughts, sensations, desires, and emotions we encounter in introspection are just plainly different from electrochemical activity in neural networks. As he summarizes the argument from irreducibility, it states that language, reasoning, the introspectible qualities of sensations, and the meaningful contents of our thoughts cannot plausibly be accounted for in materialist terms; for example, knowledge of the molecular structure of a rose and/or of the brain would not allow a physicist or chemist to predict what it would be like to experience the smell of a rose.

Churchland’s summary of these arguments is superficial. For example, it is clear from his gloss on the argument from irreducibility that he regards Frank Jackson’s famous “knowledge argument” as an important instance of it. Yet he does not actually state Jackson’s argument, thus denying the unwary reader an opportunity to appreciate its full power. (Churchland does briefly discuss Jackson’s argument later in the book, but only after having disposed of dualism and plumped for materialism, thus giving the misleading impression that the argument is merely a puzzle an already-established materialism must solve rather than an independent argument for dualism in its own right.)

Worse than this, though, are the responses he gives to the two arguments in question, which are presented as decisive but are in fact exceedingly feeble. The argument from introspection has no force, Churchland assures us, because introspection cannot be trusted in light of the fact that there are clear cases from the history of science showing that our natural powers of observation have misled us in other domains. What cases are these? “The red surface of an apple does not look like a matrix of molecules reflecting photons at certain critical wavelengths, but that is what it is,” Churchland says; “The sound of a flute does not sound like a sinusoidal compression wave train in the atmosphere, but that is what it is. [etc.]”

The problem with this response should be obvious, at least to someone with knowledge of the history of the mind-body problem and of modern philosophy generally. In particular, there is an obvious reason why the cases Churchland appeals to not only do not make the point he thinks they do, but in fact make the case for dualism even stronger. For the reason the identities in question – red with such-and-such a light wavelength, sound with a such-and-such a wave pattern, etc. – are plausible in the first place is that the early modern thinkers who inaugurated the “mechanical” conception of nature that informs modern science introduced a crucial distinction between features of the observable world that are observer-relative and those that are observer-independent – the famous primary quality/secondary quality distinction (spelled out in different ways by Galileo, Descartes, Locke, et al.). Colors, sounds, heat, cold, and the like as common sense understands them were relegated to the “observer-relative” side of the divide, and color, sound, heat, cold, etc. as objective, physical properties were, accordingly, redefined in terms of wave activity, the motions of particles, or some other “observer-independent” phenomena.

To see how this works in the case of one of Churchland’s examples, let’s distinguish between RED (in caps) and red (in italics) as follows:

RED: the qualitative character of the color sensations had by a normal observer when he looks at fire engines, “Stop” signs, Superman’s cape, etc. (which is different from the qualitative character of the sensations had by e.g. a color blind observer)

red: whatever physical property it is in fire engines, “Stop” signs, Superman’s cape, etc. that causes normal observers to have RED sensations

Now what seems to common sense to be very different from “a matrix of molecules reflecting photons at certain critical wavelengths” is RED. And sure enough, what science has shown to be identical to “a matrix of molecules reflecting photons at certain critical wavelengths” is only red, not RED. Indeed, part of the reason for distinguishing red and RED is precisely that RED seems clearly not to be identical to something like “a matrix of molecules reflecting photons at certain critical wavelengths,” since the “matrices of molecules” etc. are what they are regardless of who is looking at them while qualitative character is observer-relative.

Part of the problem with Churchland’s response to the argument from introspection, then, is that it commits a fallacy of equivocation: The sense of “red” in which “Red seems different from any property of a matrix of molecules etc.” (i.e. RED) is different from the sense of “red” in which “Science has shown that red really is just a property of a matrix of molecules etc.” (i.e. red). A similar fallacy is committed when he appeals instead to sounds or any other sensory qualities. Thus his examples do not show that our powers of observation have misled us in other domains, and thus should not be trusted in the case of introspection.

That’s one problem with his response. Another is that when we understand what is really going on in the history-of-science examples Churchland appeals to, we can see that they actually strengthen the case for dualism rather than undermine it. For if colors, sounds, heat, cold, etc. as common sense understands them – that is, in terms of their qualitative, phenomenal character – exist only in the mind of the observer and not in the physical world (which is comprised of nothing more than colorless, odorless, soundless, tasteless particles in motion, or whatever), then it seems clear that they cannot exist in the brain, or in any other physical object or system of physical objects, either. Hence they must be immaterial. As I have noted before, that was exactly the conclusion explicitly drawn by early modern thinkers like Cudworth and Malebranche – and at least implicitly by Descartes, Locke, and the other early modern advocates of the “mechanical philosophy” who also happened to be dualists – and by several philosophers since. Their view was that dualism, far from being a pre-scientific holdover destined to be abandon once we have sufficient knowledge of the brain, in fact follows from the very mechanistic conception of matter taken for granted in modern science. The basic problem was one of the themes of Thomas Nagel’s celebrated 1974 article “What is it like to be a bat?” (though Nagel is less committal there about precisely what philosophical conclusion we ought to draw from the problem). It was explicitly appealed to in defense of dualism in Richard Swinburne’s 1986 book The Evolution of the Soul.

Now Churchland or some other materialist might think there is a way to carve up the conceptual territory that doesn’t have such an implication. Fine and dandy, let’s hear it and evaluate it. But he oughtn’t to pretend that the “reductions” in question clearly favor materialism when in fact, historically, they were taken to favor the opposite view! And, especially, he oughtn’t to convey this false impression when purporting to offer an evenhanded presentation of the case for dualism.

Churchland’s treatment of the argument from irreducibility is equally bad. As evidence that our powers of reasoning can in fact be accounted for in materialistic terms, he appeals to the existence of electronic calculators. As evidence that language can be similarly accounted for, he appeals to the existence of “computer languages.” He fails even to mention the most glaringly obvious reply to such “explanations” – that they involve nothing more than a couple of bad puns, since so-called calculators don’t literally “calculate” and computers don’t literally possess “language.” Rather, both electronic calculators and computers generally are inherently devoid of any intentionality or powers of reasoning whatsoever, and have simply been designed by human beings – who do have genuine powers of reasoning and language – to carry out certain operations that aid us in our exercises in calculation and the like by simulating certain mental processes. To “explain” mental phenomena in terms of what computers do is thus precisely to get things back-asswards, since what computers do cannot be accounted for apart from the human minds which assign to their states and operations whatever meanings they have.

Again, the point isn’t that Churchland might not have a way to respond to such arguments. The point is that he pretends that the claims he makes easily and uncontroversially rebut the argument from irreducibility when in fact his claims are extremely controversial even among non-dualists. (John Searle and Hubert Dreyfus are only the two most prominent non-dualist philosophers to have criticized the suggestion that mental processes can be explained in terms of “computational” ones.) The hapless beginning student coming away from Churchland’s discussion would have no idea that his “Gee whiz, look what computers can do!” shtick is, by itself anyway, philosophically about as serious as “proving” that time travel is theoretically possible based only on what one saw once in a Star Trek episode.

Churchland also suggests that whatever explanatory difficulties materialism has are at least equally matched by any dualist attempt to explain mental phenomena in terms of “nonphysical mind-stuff.” Here again Churchland proves only that he doesn’t understand what the main arguments for dualism actually say. As I noted in my first post in this series, those arguments are not quasi-scientific “explanatory hypotheses” in the first place, but rather attempts at metaphysical demonstration. They do not “postulate” “mind-stuff” (whatever that is) any more than mathematicians “postulate” the existence of the number 48 as the “best explanation” of why 47 and 49 do not fall right next to each other in the series of natural numbers. If the arguments fail, they do not fail for the sorts of reasons that explanatory hypotheses fail (considerations of parsimony, lack of fit with existing empirical theory, etc.), any more than an attempted mathematical proof, when it fails, can fail for such reasons.

But that brings us to Churchland’s positive arguments against dualism, which we’ll look at in a third post.

Churchland on dualism, Part I

We have been hammering away at eliminative materialism (EM) in a series of posts. If EM proponents fail to make their own position plausible or even coherent, how do they fare as critics of alternative views? Not much better. Let’s look at Paul Churchland’s treatment of dualism in (the 1988 revised edition of) his textbook Matter and Consciousness. (There’s the book’s cover at left. It’s better than the book itself, which I guess confirms the old adage. I considered using this illustration, but it seemed a bit impolite.)

There are two main problems with Churchland’s discussion. First, his summary of the case for dualism is no good. Second, his arguments against dualism are no good either. In this post we’ll look at the first problem and in a second post I’ll address the second.

What are the main arguments for dualism? Churchland identifies four; he calls them the argument from religion, the argument from introspection, the argument from irreducibility, and the argument from parapsychology. To anyone familiar with the philosophical literature on dualism, this list cannot fail to seem very odd.

One problem with it is that it includes two arguments – the “argument from religion” and the “argument from parapsychology” – that dualist philosophers actually put little or no emphasis on. As Churchland presents the “argument from religion,” it amounts to little more than the claim that “Dualism must be true, because my religion says it is.” He cites no philosophers as actually having given this argument, no doubt because there aren’t any. (Yes, a philosopher who happens to believe on independent grounds that his religion is true and that it entails dualism might present that as an argument for dualism to someone who already agrees with its premises. But no dualist philosopher I can think of has ever pretended that such an argument would be a good stand-alone argument for convincing either an irreligious materialist or even someone whose attitude toward either religion or dualism is noncommittal.)

The “argument from parapsychology” no doubt does have some defenders; certainly there are serious philosophers who have taken the subject of alleged paranormal phenomena seriously either in a sympathetic way (e.g. C. D. Broad and, in recent years, Stephen Braude) or in a critical spirit (e.g. Antony Flew). But this subject does not in fact play much of a role in contemporary debates over dualism, and even those philosophers who believe that at least some purported paranormal phenomena cannot plausibly be explained away in terms of existing scientific theory (e.g. Braude) do not necessarily put such claims forward, primarily or at all, as grounds for accepting dualism.

It is in any event a mistake to think that dualism is intended as a kind of scientific hypothesis put forward as the “best explanation” of the empirical evidence, parapsychological or otherwise. The central arguments for dualism have always been attempts at metaphysical demonstration, intended to show conclusively that whatever the mind is, it cannot even in principle be material. And this brings us to the most glaring fault with Churchland’s list: He simply ignores these key arguments entirely. For example, though he purports to summarize Descartes’ own reasons for endorsing dualism, and rightly notes that Descartes thought that certain key mental phenomena are irreducible to material phenomena, he fails even to mention the two arguments Descartes put the most emphasis on: the clear and distinct ideas argument (these days often called the conceivability argument or the modal argument), and the indivisibility argument (which is related to what is often called the unity of consciousness argument). The first argument (which I have discussed in a previous post) holds that since – the argument claims – it is metaphysically possible for mind to exist apart from anything material, it cannot be material. The second holds that the mind has a kind of unity or indivisibility-in-principle that nothing material can have. (Variations on this basic idea were also defended by the likes of Leibniz and Kant.)

It isn’t like these arguments are not well known. Nor are they mere historical relics; they have defenders to this day. (For those who are interested, I discuss them in detail in my book Philosophy of Mind.) The modal argument in particular received renewed attention in the wake of Kripke’s Naming and Necessity, and thus in the years leading up to the publication of Churchland’s book. It was defended by Richard Swinburne in The Evolution of the Soul, which appeared in 1986 – two years before Churchland’s revised edition – and by W. D. Hart in The Engines of the Soul, which itself came out in 1988. (Charles Taliaferro is another philosopher who has defended it in the years since, in his book Consciousness and the Mind of God.)

Churchland also ignores – as, in fairness, almost all contemporary philosophers of mind do – what early modern writers like Malebranche regarded as the central proof of dualism, viz. that dualism follows from the very mechanistic conception of matter Cartesians and materialists hold in common. For if color, odor, taste, sound, etc., as common sense understands them, do not exist in matter itself but only in our perceptual experience of matter, then those experiences cannot be material. (I have discussed this argument in previous posts as well, e.g. here and here.)

What is in fact the chief argument for dualism, at least from the point of view of the classical (Platonic-Aristotelian-Thomistic-Scholastic) traditions in philosophy, concerns, not sensory qualities or “qualia,” but rather our capacity for abstract thought. For concepts, and our thoughts about them, are universal in a way nothing material can be, and (sometimes, anyway) determinate, precise, or unambiguous in a way nothing material can be. (I have discussed this sort of argument too in many earlier posts, e.g. here and here.) While this line of argument has also been largely ignored by contemporary academic philosophers of mind, it was defended by Mortimer Adler in the years leading up to the publication of Churchland’s book, and by 20th century Thomist writers generally. Needless to say, Churchland ignores it as well.

So, while Churchland pretends to be summing up “some of the main considerations” usually given in support of dualism, he completely ignores the arguments the most prominent dualist philosophers actually regarded as the most important, and includes arguments that dualists do not typically make use of – arguments that are either clearly feeble (the “argument from religion,” as Churchland presents it) or which rest on premises which are as controversial as dualism itself is (the “argument from parapsychology”). The rhetorical effect is obvious: The unwary reader, who assumes that a textbook will give him an accurate summary of what each side has to say, is bound to come away with a completely distorted conception of the case for dualism. In particular, he is bound to think it far weaker than it actually is.

I am not claiming that Churchland is knowingly perpetrating what looks like a pretty sleazy rhetorical tactic. I think he is, like most materialists, simply ignorant of what most dualists have actually said. He no doubt thinks he knows enough about what they say to be justified in concluding that their position is not worth looking into any further than he already has. He is wrong, but will never know that he is, because he has gotten himself onto the sort of merry-go-round that (as we have seen in recent posts) naturalists seem to have so much difficulty keeping off of: “I know that dualism is too silly to investigate any further because of how bad the arguments for it are; and I know that I must be understanding those arguments correctly because dualism is obviously just too silly to be worth investigating any further.”

The thing is, books like Matter and Consciousness contribute to the formation of the same mindset in others. As generation after generation of philosophy students are taught out of such books, the conclusion that dualism is intellectually disreputable comes to seem something that “everyone knows.” In fact, what “everyone knows” is nothing more than a bunch of straw men and circular arguments, bounced around the materialist echo chamber long enough that no one can hear anything else. (This is, of course, exactly parallel to what most atheist philosophers “know” about the classical arguments for God’s existence, as I have noted here, here, and here. The hegemony of atheism and materialism crucially depend on a stubborn and studied ignorance of what theists and dualists have actually said.)

Having said all that, Churchland is at least correct to say that what he calls the "argument from introspection" and the "argument from irreducibility" are prominent arguments for dualism. Unfortunately, what he says about these arguments is no good either. We’ll see why in part II.

Give me that old time atheism

Last night I was dipping into Roy Abraham Varghese’s Great Thinkers on Great Questions, an interesting collection of interviews with a number of prominent philosophers (including A. J. Ayer, G. E. M. Anscombe, Alvin Plantinga, Richard Swinburne, Ralph McInerny, Brian Leftow, Gerard Hughes, and many others) on topics mostly related in one way or another to religion. Some of Ayer’s remarks brought to mind how different earlier generations of agnostics and atheists had been, not merely culturally (as Roger Scruton has noted) but philosophically. Ayer, though a notorious lifelong foe of religion, was not a materialist. In his famous book Language, Truth, and Logic, he attempted (as he reminds us in the Varghese volume) to reduce physical objects to “sense-contents,” entities which were intended to be neutral between mind and matter but which were in fact (as Ayer admits) closer to the mental than to the physical side of the traditional mental/physical divide. Hence the resulting position was “much more nearly mentalistic than physicalistic.” And to the end of his life he apparently always rejected any attempt to reduce the mental to the physical.

The reason for this is that even agnostic and atheist philosophers of Ayer’s generation generally recognized that materialism is just prima facie implausible. As I have noted in some earlier posts (here and here), and as I discuss at length in The Last Superstition, dualism was by no means a deviation from the broadly mechanistic conception of matter contemporary philosophy has inherited from the 17th century, but rather a natural consequence of that conception, given its highly abstract and mathematical redefinition of the material world. If matter is what the mechanistic view says it is, then (it seems) there is simply nowhere else to locate color, odor, taste, sound, etc. (as common sense understands these qualities, anyway), and nowhere else to locate meaning (given the banishment of final causes from the material world), than in something immaterial. And until about the 1960s, most philosophers (the occasional exception like Hobbes notwithstanding) seemed to realize that, short of returning to an Aristotelian hylemorphic philosophy of nature, the only plausible alternatives to dualism were views that tended to put the accent on mind rather than on matter – such as idealism, phenomenalism, or neutral monism.

The last of these, as its name implies, was officially committed to the view that the basic stuff out of which the world is constructed is “neutral” between mind and matter, but notoriously it tends to collapse into either phenomenalism or idealism. In my atheist days, it was the version of neutral monism developed by Bertrand Russell (or rather a riff on that version developed by F. A. Hayek) that I took to be the most plausible approach to the mind-body problem. (In recent philosophy, Russell’s views have been developed, in a way that seeks to avoid any sort of idealism, by Michael Lockwood; and, in a way that to some extent or other concedes their idealistic implications, by Galen Strawson and David Chalmers. In my Russellian days I was more attracted to Lockwood’s approach.) After a brief flirtation with materialism while an undergrad, I was more or less inoculated against it by John Searle’s writings, and came to regard the Russellian approach as the most plausible way to defend a naturalistic (if non-materialistic) view of the world.

Most naturalistic philosophers are not at all attracted to this approach, however, precisely (I would suggest) because of its tendency to collapse into some sort of philosophical idealism. For to make mind out to be the ultimate reality is – as the history of 19th century idealism shows – to adopt a view which must surely strike most naturalists as “too close for comfort” to a religious view of the world. To be sure, Chalmers and Strawson do not take their position in anything like a religious direction, but so far few other naturalists have been willing to follow them.

But if they were wise, they would do so. Chalmers and Strawson are in fact among the most interesting philosophers of mind writing today, in part because of their attempt to defend a kind of naturalism while acknowledging the very deep philosophical difficulties inherent in materialism. (Strawson famously dismisses materialism as “moonshine.”) As I have been lamenting in recent posts, most contemporary philosophical naturalists (to say nothing of non-philosophers who are naturalists, such as the New Atheists) have only the most crude understanding of the theological views they dismiss so contemptuously. In the same way, they tend also to be absurdly overconfident about the prospects of a materialist or physicalist account of the mind.

Earlier generations of philosophical atheists or agnostics – Ayer, Russell, Popper, to name just three – knew how difficult it is to defend such an account, and thus avoided grounding their atheism or agnosticism in a specifically materialist metaphysics. Some of their contemporary successors – Lockwood, Chalmers, Strawson, Nagel, Searle, Fodor, McGinn, Levine, among others – have, to varying degrees, some awareness of the same problems. Consequently, at least some of these people realize that naturalism itself (which seems most plausible precisely when spelled out in materialist terms) is by no means obviously right; it is something that requires a very great deal of effort to defend, and cannot blithely dismiss its rivals. Unfortunately, the bulk of contemporary philosophical naturalists – Dennett and Rey being by no means idiosyncratic in this regard – seem forever lost in their dogmatic slumbers.

ADDENDUM: I should note that Strawson does sometimes call his version of Russell's position "real materialism," and that Lockwood has occasionally said similar things. By contrast, Grover Maxwell, another Russellian who influenced both Lockwood and Strawson, repudiates any kind of "materialist" label even though his views are more or less identical to theirs. And Chalmers sometimes characterizes his own variation on Russellianism as a kind of "dualism"! So, the terminology here can get confusing. The point is that all of these authors reject materialism in the standard (Smart, Armstrong, early Putnam, Davidson, Dennett, Churchland, et al.) sense.