Thomas Aquinas on Bodily Identity by Antonia Fitzpatrick (review)

A substantial debate has been prolonged in recent years over Aquinas’s theory of the continuity between (a) the human being in this life, (b) her soul surviving death, and (c) the resurrected human being in the eschaton. Regarding the transition from (a) to (b), is Aquinas a corruptionist (holding that at death one kind of substance is replaced by another), or a survivalist (holding that the human person survives but in a radically mutilated state)? Even more puzzling, and correspondingly less studied, is the relationship between (a) and (c). What does it take for the resurrected human being to be authentically me?

The difficulty for readers of Aquinas is this: His hylomorphic metaphysics seems to entail that having the same substantial form (soul) should be enough to preserve the numerical identity between my body now and my resurrected body in the future. Yet Aquinas insists that, additionally, my resurrected body must contain at least some of the “numerically same matter” as it has now. But what could possibly guarantee the sameness of the matter, if not its form? The question of what identifies a body as numerically one across time is important not only for resurrection, but also for other areas of Aquinas’s metaphysics of bodies, including the status of prime matter as opposed to “proper matter,” the role of “indeterminate dimensions” in individuation, and his rejection of a so-called form of bodiliness (forma corporeitatis) in favor of a single substantial form for a single body.

With Thomas Aquinas on Bodily Identity, Antonia Fitzpatrick has written the first book devoted to this problem of “bodily identity” in Aquinas. The book’s appeal consists in the refreshingly context-sensitive lens it brings to these topics. Fitzpatrick contextualizes Aquinas’s account of bodily identity in relation to the sources (especially Aristotle and Averroës) that helped shape that account. She also introduces problems such as embryology and generation, whose relevance to his account of bodily identity has generally been overlooked. This approach generates big expectations: Fitzpatrick claims to discover in Aquinas a movement toward a kind of quasi-mathematical structure to matter. This movement, she claims, shows Aquinas’s keenness to give the body its “autonomy” from the soul.

These promises, however, are not fully borne out. Interpretively, the book actually hews quite close to the standard scholarly understanding of Aquinas’s account of individuation and identity. With respect to the overarching narrative concerning the body’s “autonomy” from the soul in Aquinas—a puzzlingly sociopolitical formulation of a metaphysical problem— the author fails in the end to provide real supporting evidence for such a strong claim. At the same time, however, some good scholarly work is done in individual sections, including an important account of how Aquinas dramatically reinterprets Averroës’s terminology of “determinate vs. indeterminate dimension.”

The first two chapters lay out the Aristotelian debates that frame Aquinas’s treatment of bodily identity. Chapter 1, “The Aristotelian Tradition (I): Individuality and the Individual Body,” lays out some basic concepts from Aristotle, including form and matter, substance and accident, human generation, and individuation. The discussion of embryonic development from De generatione et corruptione here is especially valuable, since this material is highly relevant to the question of bodily identity, but seldom considered.

Chapter 2, “The Aristotelian Tradition (II): Bodily Identity,” turns to the main topic of the book, bodily identity. Aristotle holds, Fitzpatrick points out, that remaining numerically the same body requires having the same matter and the same form; conversely, when one substance is corrupted and a new one is generated, the new substance does not have the same matter and form as the old one. Fitzpatrick wonders how Aristotle reconciles this claim with his view that some “substrate” must endure through any change (60–62). But there is no puzzle here: For Aristotle, the matter that does not endure through change is proper matter (e.g., the different kinds...