Here’s a thumbnail history of philosophy and science since the early modern period, in three stages. First, the Aristotelian-Scholastic tradition had by the beginning of this period hammered out a conception of the natural world that is at the same time unified and radically anti-reductionist. It is unified insofar as to all natural phenomena we can apply the theory of act and potency, the hylemorphic analysis of material substances, the doctrine of the four causes, and other components of Aristotelian philosophy of nature. It is radically anti-reductionist insofar as it affirms that certain divisions in nature -- between the inorganic and the organic; between the merely “vegetative” or non-sentient forms of life and the sensory or animal forms; and between the merely sensory or animal forms of life and the distinctively rational or human form -- are nevertheless differences in kind rather than degree.
Then, Galileo, Descartes, Newton, and Co. inaugurated a new, mathematical conception of the world which eschewed formal and final causes and the rest of the Aristotelian philosophy of nature. Its dramatic predictive and technological successes in physics would lead to the dream of unifying all of the sciences in a reductionist way, with the new mathematical physics being that to which everything else would be reduced. The differences in kind affirmed by the Aristotelian-Scholastic tradition would turn out to be differences in degree, merely more complex variations on the same kind of stuff physics tells us about. The high tide of optimism about this program was probably the logical positivist movement of the early twentieth century.
Finally, by the late twentieth century it became clear that positivism was a failure and that no reductionist program would succeed. Moreover, the traditional Aristotelian divisions in nature stubbornly persisted: The irreducibility of rational life to sub-rational forms of life manifested itself in the failure of projects in contemporary philosophy of mind to provide a naturalistic account of the “propositional attitudes”; the irreducibility of sentient life manifested itself in the failure of attempts in the philosophy of mind to provide a naturalistic account of “qualia”; and regarding the reduction of the organic to the inorganic, as atheist philosopher Alva Noë writes, “we don't have any account of how life springs forth from the supposed primordial soup. This is an explanatory gap we have no idea how to bridge.” (See David Oderberg’s contribution to Aristotle on Method and Metaphysics for a recent Aristotelian defense of the irreducibility in principle of the organic to the inorganic.)
As the century ended, a small group of Neo-Scholastics, joined by a few neo-Aristotelian defectors from the ranks of analytic philosophers, stood at the back of the crowd, barely audible above the din, yelling: “Helloooo… um, guys? Toldyou so!” The few others in the back who heard gave a puzzled shrug and went back to reading Jobs for Philosophers.
Jump to the present, and the controversy over Thomas Nagel’s Mind and Cosmos. As I noted in my series of posts on the controversy, though it is not clear that he realizes it, in his views regarding rationality, consciousness, and the origins of life, Nagel has essentially recapitulated the traditional Aristotelian division -- and Noë, in responding to Nagel, does so too, at least implicitly. I also noted how the standard shtick among Nagel’s critics was to express incredulity that Nagel should think reductionism anything other than a straw man. “Hey Tom, the 1960s called -- they want their copy of The Structure of Science back. Don’tcha know there ain’t nobody in here anymore but us non-reductionists?”
I also noted, though, that this response cannot suffice. For the problem facing a “non-reductive naturalist” is to show exactly how his view fails to collapse into either some form of dualism (or perhaps panpsychism, neutral monism, or other non-materialist position), or a return to the Aristotelianism that the contemporary naturalist’s early modern ancestors were supposed to have moved us beyond for good. Nagel, who sees the problem, opts in part for a kind of neo-Aristotelianism.
At the Opinionator blog at The New York Times, philosopher of science Philip Kitcher has offered his own fair minded and non-polemical response to Nagel’s book. William Carroll has replied to Kitcher, from an Aristotelian-Thomistic point of view, over at Public Discourse. Give them both a read.
To what Bill says in reply to Kitcher, I would add the following. Like other Nagel critics, Kitcher agrees that reductionism has failed. The “Newtonian vision” promised a “cosmos in which everything would be explained on the basis of a small number of physical principles.” But this, Kitcher says, is not what science has actually delivered. It has given us “no grand theories, but lots of bits and pieces, generating local insights about phenomena of special interest.” And the future of science promises to continue in this vein, taking us beyond “the illusion of unity” and replacing it with “an enormous and heterogeneous family of models.”
What about the specific aspects of nature emphasized by Nagel? Kitcher doesn’t seem to dispute that they have not been explained the way reductionistic science and naturalistic philosophy promised. He acknowledges that “we lack a physico-chemical account of life” and indeed that the problem of giving such an account “hasn’t been directly addressed by the extraordinary biological accomplishments of past decades.” And he allows that scientists have an “incautious tendency… to write as if the most complex functions of mental life — consciousness, for example — will be explained tomorrow.”
So, what then is Kitcher’s alternative answer to the questions reductionist science and naturalistic philosophy have failed to answer, and to which Nagel offers a (partially) neo-Aristotelian answer? He doesn’t have one. Instead he suggests that we stop asking the questions. More precisely, with respect to the nature of life, he proposes: “[D]on’t ask what life is (in your deepest Newtonian voice); consider the various activities in which living organisms engage and try to give a piecemeal understanding of those.” He recommends taking a similarly piecemeal approach to answering questions about mind, and forgetting about whatever won’t succumb to this method. “With luck, in a century or so, the issue of how mind fits into the physical world will seem as quaint as the corresponding concern about life.” For “philosophy and science don’t always answer the questions they pose — sometimes they get over them.”
Well, “get over it” is, needless to say, not an answer we would accept in other contexts. When you give the cashier a twenty for the three dollar coffee you just purchased and he hands you back seven dollars, “Get over it” is no answer to the question “Where’s the other ten?” When you go into the hospital for an appendectomy and awaken to find your legs missing, “Get over it” is no answer to the question “What the hell did you do to me?!” And, needless to say, “Get over it” is no answer Kitcher or any other naturalist would accept in response to criticism of a theological proposition. So why should we give naturalists a pass we wouldn’t give to theologians, surgeons, and cashiers?
It’s worse than that, though. For when someone offers you a unified explanation of the world -- as Nagel does, in a very sketchy way, and the Aristotelian-Scholastic tradition does in a rigorously worked out way (and a way that can incorporate what we’ve learned from modern science, as present day representatives of the tradition have shown) -- it is no response whatsoever to say: “Well, I’ve got this alternative view of the world on which there is no unified explanation.” The only thing to say to that is: “Um, thanks for sharing, but I’ve just given you a unified explanation. So what you need to do, if your rejection of it is going to be rational, is to show me exactly what is wrong with it, and not just question-beggingly assert that there is no explanation, or that acceptable explanations have to fit into your Procrustean philosophical bed.”
Actually, it’s worse even than that. For the main philosophical selling point of naturalism has, of course, always been the idea that it can explain everything its rivals can but in a more economical way. The original claim was that we don’t needall that Aristotelian metaphysics (or the Cartesian, idealist, or other non-naturalistic metaphysics that replaced it) in order to account for rationality, sentience, life, etc. Ockham’s razor and all that. And Ockham’s razor, of course, says: Don’t multiply entities beyond necessity. It doesn’t say: Don’t multiply entities when doing so would be tantamount to an embarrassing admission that naturalism can’t after all perform as advertised. And if it turns out you do need the entities for explanatory purposes, then multiply away.
Nagel’s proposal is like that of the honest salesman who gives you a refund when his product doesn’t do what he said it would do. I’m sorry ma’am, here’s your money back. You should have stuck with Aristotelianism rather than that new-fangled Elixir of Materialism I was peddling. In fact I now rep the Stagirite brand myself!
Kitcher’s proposal, by contrast, makes of naturalism (whatever his own intentions) something of a bait and switch. Naturalism will explain mind, life, etc.? A unified metaphysical picture of the world? Did I say that? Hmm, doesn’t ring a bell, lady. Must’ve been some other salesman. Anyway, the check’s cashed and you already signed the contract. But hey, have a look at these really interesting recent findings of molecular biology. Might lead to some new pharmaceuticals…
Or to switch metaphors, Kitcher’s brand of naturalism transforms it into something like a politician accused of corruption, who repeatedly and indignantly denies the charges made against him -- until the evidence of his guilt becomes overwhelming, after which he dismisses the charges as old news, no big deal, not as bad as what his opponent is guilty of, etc. Of course naturalism will explain life, mind, the whole ball of wax. And, mark my words, in a reductionist way. Anyone who says otherwise is a bigoted ignoramus. Except that, well, yes, there are all these problems with our accounts of life, mind, etc. And yes, reductionism is a failure. But come on, we’ve always known that. Nobody cares. Why do you keep bringing it up?
Not that Kitcher himself is playing politics. As I said, his remarks on Nagel are fair-minded and non-polemical. But his approach is, I think, hopeless. And if you don’t know that political concerns are driving a lot (not all, but a lot) of the response to Nagel, you haven’t been reading the reviews.
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