Reviewed by: What Is a Person? Realities, Constructs, Illusions by John M. Rist Eileen C. Sweeney John M. Rist. What Is a Person? Realities, Constructs, Illusions. Cambridge: Cambridge University Press, 2020. Pp. vii + 288. Cloth, $34.99. John Rist's What Is a Person? is a scholarly, rich, and trenchant study of the history of the concept of personhood in Western thought. However, its sharp critique of modern and postmodern accounts of personhood, though thought-provoking, also uses jarringly polemical language, which further undermines the book's flawed overall argument. The first section, "Constructing the Mainline Tradition," carefully mines ancient and medieval sources, tracing with nuance and complexity the different threads in the notion of person. The threads are religious, philosophical, legal, and literary, and the philosophical sources are multiple. Rist does not privilege Boethius's definition in Contra Eutychem et Nestorium of person as "individual substance of a rational nature" (3) so influential in Christian theology, but explores different approaches from the Stoics and Neoplatonists, as well as from Plato and Aristotle. For example, from Cicero by way of Panaetius we get the four layers of personhood: personhood (1) in virtue of a common nature, (2) as a unique individual, (3) as the subject of historical circumstances we do not choose, and (4) as the professions we do choose (27–28). In the Stoic tradition, the individual person is grasped as "uniquely distinct" with the soul as the "source" of its "essential diachronic unity" (33). Augustine, though not at first, ultimately asserts that the human person is not the soul alone but the "miraculous combination" of body and soul (49), both "objective reality" and "subjective historical structure" (55). Rist argues that these multiple sources get lost in the emphasis on Boethius's definition, especially as these sources are pulled into the Aristotelian framework in the Middle Ages, and that, moreover, as Aristotelianism came under attack, the notion of personhood constructed too exclusively in its terms was further weakened. Rist also points out two important "gaps" in Aquinas: first, the claim that individuals cannot be known but only sensed qua individual, and second, that individuation is through matter (67–68). The latter leaves Aquinas struggling to maintain the individuality of the person, not just the body, and the former fails to recognize, as Augustine did, that we do know individual persons, for example, through biography and history (67–68). What is compelling about this story is the careful elucidation of multiple strands grounded in very different kinds of philosophical principles. However, this makes the conceit of the book even more surprising and untenable, namely that there is a mainline tradition, all the pieces of which are absolutely necessary and must be combined with the view that the dignity of persons is conferred by the creator God. The mainline tradition is a fiction; even according to Rist himself, it never coalesced. And what did not coalesce it makes no sense to hypostasize as the object of relentless (and mostly construed as malevolent) attacks from Scotus to the present day. Before he begins his journey through modernity and the nineteenth century toward "the final solution" (from the title of part 4: "Persons Restored or Final Solution," 200), Rist claims that thinkers after Aquinas "have much to contribute" to the mainline tradition. However, he continues, they do not add to or support the "worth" of the person but "merely" add "new information" (69, emphases in the original) because—though Rist never really argues for this claim—it is impossible to establish the worth of persons unless one holds that it is divinely given. Further, Rist's analysis of the modern "contributions" of "new information" (69), even when incisive, is always the story of the undermining of personhood, whether intentionally or in the attempt to save or refound it. Part 2, discussing Descartes, Hobbes, Locke, Richardson, Hume, Smith, Rousseau, and Kant, is entitled "No God, No Soul: What Person?"—and the answer is clearly "none." Part 3 delves into the "swamp" (Rist's term) of the nineteenth century to find five attempts to "save" the person but which, he says, point "variously to homogenization, debasement and ultimately nihilistic despair as the destiny of the...