To untutored common sense, the natural world is filled with irreducibly different kinds of objects and qualities: people; dogs and cats; trees and flowers; rocks, dirt, and water; colors, odors, sounds; heat and cold; meanings and purposes. A man is a radically different sort of thing from a rose, which is in turn no less different from a stone. The warmth of the stone and the redness and fragrance of the rose are features no less real than their shapes or movements; the function of an ear or an eye and the meaning of a human thought or utterance are no less a part of objective reality than a man’s height or weight.
Aristotle and the Scholastic tradition that built on his thought took the view that common sense was essentially correct. It needed to be systematized and refined, and when its implications were drawn out they would lead to metaphysical conclusions far beyond anything the man on the street is likely to have dreamed of, or even to understand. But a sound philosophy and science would nevertheless build on common sense rather than radically undermine it.
The founders of modern philosophy and science overthrew Aristotelianism, and common sense along with it. On the new view of nature inaugurated by Galileo and Descartes, the material world is comprised of nothing more than colorless, odorless, soundless, meaningless, purposeless particles in motion, describable in purely mathematical terms. The differences between dirt, water, rocks, trees, dogs, cats, and human bodies are on this view superficial.
Indeed, at bottom these are all just the same kinds of thing—arrangements within the one vast ocean of physical particles, the differences between the arrangements ultimately no deeper than the differences between waves on the same sea. Color, sound, odor, heat, and cold—understood in the qualitative way common sense understands them—are relegated to the mind, existing only in our conscious representation of the natural world, not in the world itself. Color, sound, and the rest as objective features would be redefined in quantitative terms—reflectance properties of physical surfaces, compression waves, and the like.
Meaning and purpose are similarly relegated to the mind in this system. We may project the meaning and purpose we find in our own thoughts and actions onto the external world, but it isn’t really there at all. What is there is only what can be captured in the language of physical science.
Descartes and some of the other moderns supplemented this austere picture of nature with a conception of the human mind as an immaterial substance that somehow interacts with those parts of the natural world we call human bodies. This Cartesian dualist position is notoriously problematic, and modern materialists have opted to throw out Descartes’ immaterial substance while holding on to his view of the material world. But their own position is, if anything, even more problematic.
The conception of matter they share with the Cartesian dualist says matter is inherently devoid of the qualitative features we know from conscious experience—color, sound, heat, cold, etc.—as well as of meaning or purpose of any kind. To deny that there is anything immaterial that has these features is therefore to imply that there is nothing at all that has them—and thus, in turn, to deny that our conscious experiences or the meanings of our very thoughts and words are real. This “eliminative materialist” position is ultimately incoherent, and few philosophical naturalists are willing to embrace it—though Alex Rosenberg’s recent The Atheist’s Guide to Reality promotes a version of eliminativism—but the conclusion that a consistent materialism leads to it is difficult to avoid.
Thomas Nagel is another prominent naturalist willing to face up to the bizarre implications of materialism, but unlike Rosenberg he takes them to constitute a compelling reason to reject materialism and look for an alternative way to formulate naturalism. Hence the subtitle of his new book Mind and Cosmos: Why the Materialist Neo-Darwinian Conception of Nature Is Almost Certainly False.
Nagel does not reject evolution per se, but only the standard reductionist interpretation of evolutionary processes. But neither does he embrace theistic evolution. (His atheism seems as firm as it was in his earlier book The Last Word, wherein he candidly wrote: “I want atheism to be true. . . . I don’t want there to be a God; I don’t want the universe to be like that.”) His aim is rather to explore the possibility of a teleology or directedness that is inherent to the natural order rather than imposed from without—and indeed to move away from the strictly mathematical and materialist conception of the natural order the early moderns bequeathed to us.
Though Aristotle’s name comes up only a couple of times in the book, it is remarkable how Aristotelian (and even Scholastic) in spirit Nagel’s proposals are, not only in his general willingness to reconsider the immanent or “built in” teleology that was at the core of the Aristotelian-Scholastic conception of nature, but also in some of his more specific theses.
For example, Nagel argues that it is impossible to explain our rational capacities in terms of the consciousness we share with lower animals; that consciousness in turn cannot easily be explained in reductive terms of any sort, and certainly not via a specifically materialist form of reductionism; that even the origin of life from inorganic chemical processes has not been given a plausible naturalistic explanation; and that in each case we need to reconsider the possibility of a teleological account. In so arguing he has essentially recapitulated the traditional Aristotelian hierarchy of irreducibly rational, sensory, and vegetative forms of life (where “vegetative” has here a technical meaning, connoting those organic functions that operate below the distinctively animal kind).
Value, which Nagel insists is a real feature of the world rather than a projection of our subjective desires or sentiments, is, he says, a byproduct of teleology “even if teleology is separated from intention, and the result is not the goal of an agent who aims at it”—again, a standard Aristotelian thesis. (He rightly suggests that theists ought to be open to the idea of immanent teleology of the Aristotelian sort. He may not be aware that medieval theologians like Aquinas were committed to precisely that.)
Throughout the book Nagel emphasizes that for phenomena like life, consciousness, rationality, and value to arise in the later stages of the history of the universe, we have to suppose they were somehow “latent in the nature of things” from the beginning—thereby hinting at the Aristotelian notion of change as the actualization of built-in potentialities, and the Scholastic principle that whatever is in an effect must in some way be contained in its total cause.
More generally, Nagel’s emphasis on the implausibility of reducing certain higher-level features of a thing to features of its parts is reminiscent of the holistic Aristotelian conception of what a natural substance is; and his theme of the possibility of reviving the teleological notion of an “order that governs the natural world from within” echoes the Aristotelian-Scholastic notion of formal and final causes.
It would certainly overstate things to call Nagel an Aristotelian, full stop. His views are too inchoate and tentative for that. All the same, given the target of his critique—the essentially anti-Aristotelian philosophy of nature we’ve inherited from Galileo and Descartes—and the content of his positive proposals, the contemporary Neo-Aristotelian or Neo-Scholastic reader will find it hard to resist a “Told you so!”
Intentionally or not, Mind and Cosmos marks an important contribution to the small but significant Aristotelian revival currently underway in academic philosophy of science and metaphysics. Nagel suggests that the current materialist orthodoxy “will come to seem laughable in a generation or two.” That would be a fitting end for a tradition that has for so long buried Aristotelian philosophy under a mountain of caricatures.
Edward Feser is the author of The Last Superstition: A Refutation of the New Atheism and Aquinas. He blogs about philosophy here.
Thomas Nagel, Mind and Cosmos: Why the Materialist Neo-Darwinian Conception of Nature is Almost Certainly False
Edward Feser, “Rosenberg Roundup”
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