Hilary Putnam, who died a couple of months ago, had some interest in the Aristotelian-Thomistic tradition, even if in part it was a critical interest. One area where this interest manifested itself is the philosophy of mind; another is the philosophy of religion. I’ll address the former in this post and the latter in a later post. Let’s consider in particular an exchange between Putnam and the analytical Thomist philosopher John Haldane in the volume Hilary Putnam: Pragmatism and Realism, edited by James Conant and Urszula Zeglen.
Some background: In a series of books and articles, Putnam put forward penetrating criticisms of materialist attempts to explain the intentionality (or “directedness” or meaningfulness) of thought in causal terms. The basic idea of such theories -- greatly to oversimplify -- is that a brain process (say) will count as a thought with the content that the cat is on the mat if it is caused by the presence of the cat on the mat. As Putnam argued, a fatal problem with such theories is that they have no way of characterizing the causal relation in question without implicitly presupposingintentionality, when the whole point of such theories is to explain how intentionality enters the picture in the first place. More generally, the notion of causation which such materialist theories require is not one to which the theorists are entitled given their notion of what counts as “physical.”
I discussed Putnam’s critique in some detail in a post a few years ago, and also in my essay “Hayek, Popper, and the Causal Theory of the Mind” (reprinted in Neo-Scholastic Essays), wherein I noted that to some extent Putnam is recapitulating an argument presented in a more rudimentary way decades earlier by Karl Popper. (When I sent Putnam that essay he confirmed that he had “had no idea” that Popper had put forward such an argument. Great minds think alike.) As I also noted in these articles, Putnam argued that to salvage causal theories of the sort he criticizes would require returning to an essentially Aristotelian conception of nature of precisely the sort materialists suppose to have been supplanted by post-Newtonian science.
Now, while Putnam is sympathetic to the anti-reductionist bent of Aristotelianism, he too resists returning to an Aristotelian conception of nature. That brings us to his exchange with Haldane. Haldane’s essay has the memorable title “Realism with a metaphysical skull,” which is a play on the title of Putnam’s book Realism with a Human Face. Putnam wants to defend the reality of the everyday, commonsense world of human experience against reductionistic materialists who are willing to affirm the reality only of what can be described in the language of physical science. Haldane argues (correctly, in my view) that doing this successfully requires defending also some version of an Aristotelian conception of nature, which is what Putnam is unwilling to do. The “human face,” in Haldane’s view, requires an underlying “metaphysical skull” to hold it up.
One of the themes of Haldane’s article is that it is -- as Putnam himself emphasizes -- a mistake to try to explain the relationship between mind and world in terms of causal relations between inner mental representations (Lockean ideas, sentences in a “language of thought,” or what have you) and physical objects. One of the problems with this approach is that it opens up a gap between mind and world which can never be closed. Another is that it presupposes too narrow an understanding of causation. Modern representationalist-cum-causal theories of the mind confine themselves to what Aristotelians call efficientcausation (and a desiccated notion of efficient causation at that). The right way to understand the relationship between mind and world, Haldane argues, is in terms of formal causation.
One application of this idea is that the right way to understand the relationship between a thought and its object is in terms of formal identity. When you judge that such-and-such an object is a triangle, what happens is that the mind takes on the very same form that the matter of which the triangle is composed has taken on. Precisely because there is, on the side of the thought, nothing material that has taken on this form, the thought is not itselfa triangle (as any material thing that took on that form would be) but merely a thought about a triangle. But precisely because it has the very same form that the triangle has, the thought is a thought about a triangle rather than about something else. Again, thought and thing are formally identical, though not identical full stop. And because of this formal identity there is no gap between mind and world that needs to be bridged in the efficient-causal terms that causal theories of thought appeal to.
In his reply to this in the Conant and Zeglen volume, Putnam notes first that he is to some extent sympathetic with Haldane’s position. In particular, he notes that some analytic philosophers have tended to distinguish sharply between concepts(as constituents of thought) and properties(as entities entirely independent of thought). Putnam is sympathetic to the idea that this sharp distinction is mistaken and that talk of “concepts” and talk of “properties” are really just two ways of talking about the same things. To the extent that this is what the Aristotelian is saying, Putnam tells us, he is happy to go along with it.
But Putnam is not happy to go along with the whole metaphysical package associated with formal causation. As far as I can tell, he raises three objections in his reply to Haldane. The first is that Putnam thinks that talk about the mind taking on the form of a triangle when it thinks of a triangle (my example, not Putnam’s) “too much suggests” that the thinking is itself a triangle -- which is, of course, absurd, and not what the Aristotelian is saying -- but that Putnam doesn’t have “the foggiest notion of what [such talk] is supposed to mean” otherwise.
Now, it’s hard for me to know what to say about this objection other than that it seems to me that Putnam is just ignoring, without answering, the details of the Aristotelian hylemorphic analysis of physical objects -- including details Haldane summarizes in his paper. Because when those details are taken account of, it just isn’t mysterious what the Aristotelian is saying (whether or not one agrees with what he is saying). Hylemorphism, to a first approximation, distinguishes between the matter or stuff out of which a physical thing is made and the form or pattern that configures that matter or stuff into a physical thing of a certain specific type. It is only the two together that make up a physical object. Hence the form of a triangle -- that is to say, the form or pattern of being a closed plane figure with three straight sides -- is not itself a triangle or any other material object. It is only matter together with this form which is a triangle.
Now, in light of that, it is hardly fair to say that talk of the intellect taking on the form of a triangle absurdly “suggests” (“too much” or otherwise) that the thinking itself amounts to a triangle. It would suggest this only if it were suggested that the matter of a triangle as well as the form is taken on by the mind. But this is precisely what is being denied, since the claim is that the form of a triangle exists within the mind without the matter. Hence a thought about a triangle no more counts even prima facie as a triangle than the form of a triangle all by itself and without matter could count as a triangle. Hence for Putnam to claim that the Aristotelian position “too much suggests” that a thought about a triangle itself just is a triangle simply ignores the whole distinction between form and matter which is the heart of the theory.
Nor will it do for Putnam to say that it is mysterious what the Aristotelian is saying if the Aristotelian doesn’t mean that a thought about a triangle just is a triangle. For the Aristotelian is simply saying that the very same form or pattern -- that of being a closed plane figure with three straight sides -- is both what makes such-and-such a material object a triangle, specifically, and what gives such-and-such a thought its specific content. A certain material object has the form or pattern of being a closed plane figure with three straight sides; that’s what makes it a triangle specifically. You grasp the form or pattern of being a closed plane figure with three straight sides; that’s what makes your thought a thought about a triangle specifically. Because it is one and the same form in both cases, we have what Haldane calls formal identity. Because, in the case of the thought, it is the form of the triangle alone, and apart from the matter, that is present, the thought is not itself a triangle. Now, one can raise all sorts of questions and objections to this, but to suggest that we haven’t even the “foggiest notion” of what it means seems to me a real stretch.
Putnam’s second objection is that there is with at least some things no one pattern that could plausibly count as the “form” or essence of the thing. He gives the example of a dog, and he says that for a molecular biologist, the DNA of a dog would count as what is essential; for a population biologist, being part of a certain reproductive population would be what is essential; for a pet lover a wild dog might not count as a “dog,” while it might count as a dog from the point of view of a scientist; dingos might count as dogs from an Australian aboriginal point of view, but as members of a different species from an American point of view; and so forth.
The problem with this is that Putnam here runs together features and descriptions of very different types, which Aristotelian-Thomistic philosophers would carefully distinguish before trying to determine the essence of a thing. We need to distinguish, for example, between a thing’s essence and its “proper accidents,” which flow from its essence. (To take the stock example, the essence of a human being is to be a rational animal, and the capacity for amusement is one of the proper accidents that flows from this essence.) We also need to distinguish between these proper accidents (or “properties,” as that term is used in Aristotelian-Thomistic metaphysics) and merely contingent accidents. (For example, unlike the capacity for amusement, skin color is a merely contingent accident of a human being, not being something that flows from rational animality as such.) We need to distinguish what is “natural,” in the Aristotelian sense that it follows from an inherent or built-in tendency of a thing, from what is “artificial” in the sense that it is true of a thing only by virtue of some extrinsic or externally imposed pattern. (Spelling this out requires the distinctions between substantial form versus accidental form, and between immanent teleology versus extrinsic teleology.) And so on. The Aristotelian theory of formal cause can be properly understood only in light of all these distinctions.
Putnam essentially conflates all the different sorts of phenomena captured by these distinctions and lumps them together as equally good candidates for “the form” or “the essence” of a thing. And that simply gets the Aristotelian position badly wrong. An Aristotelian metaphysician looking for the essence of dogs would say, first of all, that cultural associations and linguistic practices of the sort that some of Putnam’s examples involve are simply not relevant to determining the essence of any natural substance like a dog. (Such assumptions and practices often mix together what are aspects of a thing deriving from its substantial form and those that involve merely accidental forms. Finding the essence is in part a matter of separating these out.) The Aristotelian would also note that reproductive capacities follow from deeper physiological facts about an animal, so that an animal’s status as a member of a reproductive population is less fundamental to what it is -- that is to say, to its essence -- than its DNA would be. But the Aristotelian would also caution against simply identifying the essence of a thing with some “hidden structure” like DNA. And so on. (All of these issues are dealt with in my book Scholastic Metaphysics, in David Oderberg’s Real Essentialism, and in writings by other Aristotelian-Thomistic philosophers.)
It is in any event no good for the critic of Aristotelianism simply to pull out of his hat some random example -- whether dogs or anything else -- note some complications or controversies in determining the essence of the thing, and declare that he’s identified some grave difficulty for Aristotelianism. This sort of objection is very common, but it is completely misguided. Not only does it typically ignore the sorts of distinctions just referred to, but it seems to assume that Aristotelians suppose that a thing’s essence can be determined fairly easily on the basis of a cursory examination.
Nothing could be further from the truth. Neither cursory inspection, nor even cursory inspection together with the complex theoretical apparatus I’ve alluded to (substantial versus accidental form, essence versus proper accidents, etc.), will typically suffice to tell us the essence of a thing. Detailed investigation of a physiological, chemical, or other scientific kind is often required in order to determine a thing’s essence, to determine what are really only proper accidents rather than part of the essence, and so forth. I know of no Aristotelian who denies this or supposes that these questions can be settled from the armchair. Nor does Aristotelian metaphysics as such ride on how such an investigation turns out -- as if the defensibility of the entire system of the four causes, the theory of actuality and potentiality, hylemorphism, etc. waits with bated breath on what the facts about dogs turn out to be! The most that would ride on the results of such an investigation is how we apply the system, not the soundness of the system itself. (For example, if it turned out even after detailed investigation that there simply was no plausible candidate for the essence of dogs, this might be interpreted as showing that “dog” is really a kind of accidental or artifactual category rather than reflective of a substantial form -- not that I think this is remotely likely.)
(Putnam also says that Haldane later suggested in response to the objection at hand that the essence of a dog might simply be the conjunctionof all of the candidates for the form of a dog cited by Putnam. But Putnam does not tell us where Haldane said this, and I find it hard to believe Haldane did or would say that, since it is just a bizarre thing for an Aristotelian to say. I think Putnam must have simply misunderstood whatever remark of Haldane’s he has in mind here.)
Putnam’s third objection against Haldane is that forms do no real explanatory work. For to say that the form or pattern being a triangle is what makes some particular triangle a triangle “sounds either tautological or nonsensical.” But the answer to this objection should be clear from what was said above. The form being a triangle -- or, as I put it above, being a closed plane figure with three straight sides -- does not suffice to make something a triangle, because both triangles and thoughts about triangles have that form, and the latter are not triangles. Being a triangle requires both the form in question and matter. Hence the claim that “the form of being a triangle is what makes some particular triangle a triangle” is not tautological or trivially true. It could be tautological or trivially true only if the presence of the form of being a triangle sufficed all by itself for the presence of a triangle, and it does not. It might also sound tautological if the words “being a triangle” were thought to capture the entirety of what it is to be a triangle, but of course that is not the case either.
The claim in question is really shorthand for something like “The form being a closed plane figure with three straight sides, when combined with matter, is what results in a triangle (as opposed to a circle, a square, a dog, etc.).” And that is not a tautological claim. (Certainly not when we go on to explicate form and matter in terms of the theory of actuality and potentiality, etc. For the hylemorphic analysis so developed, far from being trivially true, is one that critics of Aristotelianism claim to be false,and a claim can’t be both false and trivially true.) Nor is the claim in question nonsensical. As I noted above, it is clear what it means, whether or not one agrees with the Aristotelian analysis. (The rote objection that explanations in terms of substantial forms and causal powers are tautologies is one I address at greater length in Scholastic Metaphysics, at pp. 43-46.)
So, Putnam’s objections fail. In fairness, though, it must be said that Putnam does try to engage with the Aristotelian-Thomistic position in a fair-minded way, and he sees its strengths -- and the ways in which neo-Aristotelian assumptions are implicit even in some of what contemporary naturalist philosophers unwittingly say -- far more clearly than these naturalists themselves do. And needless to say, Putnam was in any event one of the great figures of contemporary philosophy, whose work always repays careful study. Again, in a future post I’ll consider how he engaged with Aristotelian-Thomistic philosophy in the context of philosophy of religion.
Nessun commento:
Posta un commento