Turner, a professor of theology at Yale, has written a fine, idiosyncratic introduction to the saint and his mind that emphasizes what he calls Thomas’ materialism ”” by which he certainly does not mean the currently fashionable and conceptually impoverished notion that nothing but matter exists. Rather, Thomas set himself against the prevailing Platonic-Augustinian “excessively spiritual account of human nature” that seemed to him to neglect our situatedness in the world ”” this world, here, with tomatoes and sisters and backaches. For Plato and his medieval Christian epigones, a soul was a different kind of substance from the body; we still tend to think of soul in these terms, whether we believe in it or not. Thomas denies that a soul is a “thing” that one “has” at all. It is rather the “substantial form,” in the Aristotelian sense, of the body ”” what accounts for its being alive in the way it is. Following Aristotle and Avicenna, Thomas rejects substance dualism, arguing that human beings are “wholly animal,” not part animal and part spiritual, like a Prius ”” the soul is not “in” the body, but is one with it as form, as act and potency are one.
I can’t do justice to Turner’s subtle explication of Thomas’ “Aristotelian physical anthropology” ”” and of his controversial God-centric theology in the “Summa theologiae”; his “Five Ways”; his conception of friendship and the Trinity and the Eucharist; and much else ”” in a brief review. Despite a few missteps in the prose ”” and a surprising overreliance upon lazy tropes of the terrorists-bad-CIA-good variety ”” Turner’s introduction is full of grace notes, such as his decision to contrast Thomas’ sense of “abstraction” with Locke’s empiricism, in order to flesh out the argument that the intellect “cannot be a material agent” (today’s pop neuroscientists would do well to consult the “Summa” on this point). And Turner deftly demonstrates why Thomas’ Third Way ”” the argument for God’s existence from necessity ”” does not commit the basic logical fallacy that many modern philosophers have contended it does.