Like Aristotle, Thomas Aquinas holds that the rational soul is the substantial form of the human body. In so doing, he takes himself to be rejecting a Platonic version of substance dualism; his criticisms, however, apply equally to a traditional understanding of Cartesian dualism. Aquinas’s own peculiar brand of dualism is receiving increased attention from contemporary philosophers—especially those attracted to positions that fall between Cartesian substance dualism and reductive materialism. What Aquinas’s own view amounts to, however, is subject to debate. (...) Philosophers (such as J. P. Moreland and Scott Rae) have claimed that ‘Thomistic substance dualism’ (TSD) centers around two beliefs: (1) the rational soul is an immaterial substance, and (2) this immaterial substance is the human person. In this paper, I argue that labeling such an account ‘Thomistic’ proves dangerously misleading—not only does Aquinas himself explicitly deny both of these claims, but he denies them for philosophically significant reasons. Furthermore, I argue that Aquinas’s own position provides an account of human nature both more coherent and philosophically attractive. (shrink)

St. Thomas is usually thought to have rejected abortion and euthanasia as murder (viz, the statement of The Sacred Congregation for the Doctrine of the Faith "On Procured Abortion"). By going back to Aquinas' own words I show that this is mistaken: that he explicitly states abortion prior to a certain point of fetal development to be non-murderous and that his position, when consistently developed, allows for euthanasia under analogous circumstances. These claims are argued by presenting an analytical expose of (...) Aquinas’ metaphysics of man and of human ontogenesis. The implications of this for current bioethical concerns are sketched briefly. (shrink)

This book shows how the mature writings of Thomas Aquinas though written in the thirteenth century have much to offer the human mind and the relationship between intellect and will, body and soul.

In lieu of an abstract, here is a brief excerpt of the content:THE CONCEPT OF PERSON IN ST. THOMAS AQUINAS: A Contribution to Recent Discussion* ST. THOMAS AQUINAS accepted and consistently defended Boethius' definition of person: "persona est substantia individua rationalis naturae." St. Thomas' analysis of this definition necessarily involves metaphysical questions because of the implications of the terms " substance" and " nature" and moreover it manifests the inescapahle imprint of the theological problematics which surrounded the issue (e.g. the (...) Trinity and the hypostatic union). Both of these influences, metaphysical and theological, have engendered problems of interpretation and criticism. Contemporary discussions of person largely either continue the scholastic controversies or adopt a modern perspective from which to expose apparent contradictions in St. Thomas' doctrine. The purpose of this article will be limited to a consideration of the metaphysical problems concerning the relationship between individual substance, universal, nature, and existence. It is hoped that such a clarification will resolve not only the neoscholastic controversies, but also some of the contemporary problems. I. BOETHIUS' DEFINITION OF PERSON AND ST. THOMAS' EXPLANATION A. BOETHIUS' DEFINITION Boethius develops his definition of person in the Liber contra Eutychen et N estorium after a careful consideration of na- * I have to thank cordially Father Brian Shanley, 0.P. for having revised completely this English version, devoting much time and energy to fit the text and the footnotes to the style of The Thomist. He adapted the version in good style and verified the Latin quotations. 435 436 HORST SEIDL ture and substance.1 In the first chapter he sets out to define nature and discovers four possible meanings. The first and broadest definition, embracing both substances and accidents, describes nature as belonging to all things which by their being can be in some way or another be comprehended by reason: "natura est earum rermn quae, cum sint, quoquo modo intellectu capi possunt." A second definition, comprising substances alone both corporeal and incorporeal, describes nature as anything that can effect or suffer something: " natura est vel quod facere vel quod pati possit." A third sense, taken from the Aristotelian analysis of the motion of natural substances, describes nature as the immanent principle of movement : "natura est motus principium per se et non per accidens." Finally, nature can also refer to the formal cause which provides the specific difference: " natura est unam quamque rem informans specifica differentia" (cf. ST Ia. 29, I ad 4). It is this last sense which is most important. In sum, "nature" is a broad term encompassing both composite beings and their causes. Boethius continues in chapter two by first narrowing the relevant sense of nature to substances (thus excluding accidents ) and then presenting a complete division of substances. The major distinction is between corporeal substances and incorporeal substances. Corporeal subdivides further into inanimate and animate, with animate dividing. into insensitive and sensitive and the latter dividing finally into irrational and rational. Incorporeal subdivides into rational and irrational (the life-principle of animals), with rational incorporeal substances being further distinguished into those that are immutable by nature (the Creator) and those that are not so by nature (the human soul and angels) but may become so by virtue of the immutable substance. Boethius then argues that person cannot be affirmed of inanimate beings or irrational animals. A 1 All citations from Boethius are taken from the Loeb text in Boethius: Theological Tractates and the Consolation of Philosophy, ed. H. F. Stewart and E. K. Rand (Cambridge: Harvard University Press, 1918). THE CONCEPT OF PERSON IN ST. THOMAS AQUINAS 437 final distinction of :substance into universal and particular leads to the conclusion that person must refer to an individual. Thus the background is set for the definition of person which opens the third chapter: " naturae rationalis individua substantia." Person must be an individual substance of a certain nature, namely rational, which nature accounts for the form or specific difference of the particular substance (the fourth meaning of chapter 1). The connection of this definition with Aristotle 's definition of man as a rational animal is unmistakable. It should also be noted that this definition of person is applicable not only to man, in whom the rational nature is not identical with his substance, but also to the... (shrink)

Although prominent Christian theologians and philosophers have assumed the truth of mind/body dualism, I want to raise the question of whether the Christian ought to be a mind/body dualist. First, I sketch a picture of mind, and of human persons, that is not a form of mind/body dualism. Then, I argue that the nondualistic picture is compatible with a major traditional Christian doctrine, the doctrine of the resurrection of the dead. Finally, I suggest that if a Christian need not be (...) a mind/body dualist, then she should not be a mind/body dualist. (shrink)

I investigate Thomas Aquinas's metaphysical account of human death, which is defined in terms of a rational soul separating from its material body. The question at hand concerns what criterion best determines when this separation occurs. Aquinas argues that a body has a rational soul only insofar as it is properly organised to support the soul's vegetative, sensitive, and rational capacities. According to the ‘higher‐brain’ concept of death, when a body can no longer provide the biological foundation necessary for the (...) operation of conscious rational thought and volition, a substantial change occurs in which the rational soul departs and the body left behind is a ‘humanoid animal’ or a mere ‘vegetable.’I argue that the separation of soul and body does not occur until the body ceases to function as a unified, integrated organism. A rational soul is not only the seat of a human being's rational capacities; it is also the principle of the body's sensitive and vegetative capacities. Since Aquinas defines a human being as a composite of soul and body, and not with merely the exercise of rational capacities, the determination of death requires incontrovertible evidence that the body has ceased all the operations that correspond to the soul's proper capacities. The evidence of this is the body's loss of its integrative organic unity and the criterion for determining when this loss occurs is the irreversible cessation of whole‐brain functioning. (shrink)

Revisions of three lectures given at Catholic University of America in March 1978. Includes bibliographical references and indexes. Introduction.--The first lecture, Eternity of the world.--The second lectures, Monopsychism.--The third lecture, Rationalism.

The major Western monotheisms, and Christianity in particular, are often supposed to be committed to a substance dualism of a Cartesian sort. Aquinas, however, has an account of the soul which is non-Cartesian in character. He takes the soul to be something essentially immaterial or configurational but nonetheless realized in material components. In this paper, I argue that Aquinas’s account is coherent and philosophically interesting; in my view, it suggests not only that Cartesian dualism isn’t essential to Christianity but also (...) that the battle lines between dualism and materialism are misdrawn. (shrink)

‘When did I, a human person, begin to exist?’ In developing an answer to this question, I utilize a Thomistic framework, which holds that the human person is a composite of a biological organism and an intellective soul. Eric Olson and Norman Ford both argue that the beginning of an individual human biological organism occurs at the moment when implantation of the zygote in the uterus occurs and the ‘primitive streak’ begins to form. Prior to this point, there does not (...) exist an individual human organism, but a cluster of biological cells which has the potential to split and develop as one or more separate human organisms (identical twinning). Ensoulment (the instantiation of a human intellective soul in biological matter) does not occur until the point of implantation. This conception of the beginning of human personhood has moral implications concerning the status of pre‐implantation biological cell clusters. A new understanding of the beginning of human personhood entails a new understanding of the morality of certain medical procedures which have a direct affect on these cell clusters which contain human DNA. Such procedures discussed in this article are embryonic stem cell research, in vitro fertilization, procured abortion, and the use of abortifacient contraceptives. (shrink)

In a recent book, I attempt to use the metaphysics of Thomas Aquinas to defend a moderate view regarding abortion: that an abortion at any time during a pregnancy should be considered a grave loss, but that it should be considered murder only after roughly the middle of the second trimester. John Haldane and Patrick Lee contend that I have misunderstood the implications of Aquinas's view, and that in fact his metaphysics supports the conclusion that a human being comes into (...) existence at the moment of conception. In this paper, I make a brief reply. (shrink)

In lieu of an abstract, here is a brief excerpt of the content:TRANSIENT NATURES AT THE EDGES OF HUMAN LIFE: A THOMISTIC EXPLORATION PHILIP SMITH, O.P. Providence College Providence, R.I. T:HE CONCEPT OF human nature as the intrinsic and wdical source of characteristic human a;ctivity has great mportanoe for natural law ethics. But olosely allied to the concept of human nature is the possibility of there being tmnsient natures in humans, and this rpossirbility has implications for human life at its (...) outer edges. What transient natures are wiill he discussed 1in detail below. Let us,say for now that they are the life principles of entities transition from one state of being to another. These forms enjoy only a temporary existence before they disappear and are replaced by other emerging forms.1 When applied to the outer limits of human existence, such transient natures offer useful insights for addressing the difficult problems of when personhood begins and when death occurs. Thomistic philosophy defines a human person a;s a combination of mrutte1· and,form, more oommorrly referred to as a unity of hody and soul.2 Relativie to the beginning of Jife and the 1 Such natures are discussed in William A. Wallace, 0.P., "Nature and Human Nature as the Norm in Medical Ethics,'' in Catholic Perspectives on Medical Morals, ed. E.D. Pellegrino et al., Philosophy and Medicine Series, Vol. 24 (Dordrecht-Boston: D. Reidel Publishing Co., 1989). This essay was originally presented at an international conference held at the Joseph and Rose Kenned,y Institute of Ethies of Georgetown UniYersity, October 13-16, 1986. For further background against which Wallace's discussion should be situated, see his "Nature as Animating: The Soul in the Human Sciences,'' The Thornist 49 (l985) : 612-6'18, and "The Intelligibility of Nature: A Neo-Aristotelian View," Rev,iew of Metaphysics 38 (1984): 33-56. 2 Thomas Aquinas, St., Surnrna Theologiae, I, q.29, a.4. 191 19Q PHILIP SMITH, O.P. onset of death, this philosophy of person raises the question of w:hen tihe soul is infused into the body and when :it is 1separated from it. Is the newly-fortiilized zygote capable of :receiving and sustaining the rational soul as its,substantirul form? Or must the genetic materials be informed by one or more transient natures before they achieve ithe internal unity and stability necessary :for personhood? At the end of life, the person dies when the soul leaves the body. Does personail death coincide with the death of the human organism as a whole? Or can the destruction of only an essential part of the body, e.g. tihe cerebral cortex, cause personal death by damaging the body so severely that it is simply incapable of supporting a :rational soul, even though the rest of the body remains intact and spontaneously alive? If so, is the remaining organism informed by a succession of transient substantiail forms that maintain its existence but at ever lower levels of life as it gradually declines toward total death? In examining these questions posed by the possibility of transient natures, my point of departure will be an analysis of transient natures themselves. Recently, William A. Wallace, O.P., has 'begun to eX!plore the philosophical meaning and implications of transient natures for issues such as these.a His findings will he summarized here. The insights gathered from the exploration of transient natures will next he applied to the questions of when personhood begins and when death occurs. This will necessarily employ a fraiilework embracing both tihe empirical and the philosophical, with the empirical looking to the available biological data and the philosophical inquiring about the impact o.f these data for determining the status of human life at its outer edges. Since Aquinas's natural philoss Wallace, "Nature and Human Nature...," pp. 23-51. Additional background for his researches, apart from the essays cited in note l above, will be found in his "The Reality of Elementary Particles," Proceedings of the American Catholic Philosophical Association 38 (1964): pp. 154-166, and "Elementarity and Reality in Particle Physics," Boston Studies in the Philosophy of Science, 2nd ed. (Lanham, Md.: University Press of America, 1983), pp. 171-183 and pp. 185-212. TRANSIENT... (shrink)