Disputes about metaphysical issues rarely make the newspapers these days. The ancient dispute about the nature and identity of the human person, however, turns out to be highly relevant to issues that Americans read about, and argue about, every day. As Yale psychology professor Paul Bloom recently observed in an op-ed piece in the New York Times, “What people think about many of the big issues that will be discussed in the next two months–like gay marriage, stem cell research and the role of religion in public life–is intimately related to their views on human nature.”
Bloom maintains that dualism–the idea that a person is a mind or a consciousness that has a body, rather than being a bodily entity–is both widespread and mistaken. We agree. Indeed, we have argued in various places that liberal positions on abortion, euthanasia, marriage, and sex, are often implicitly based on the false idea that human beings are essentially non-bodily persons who inhabit and use non-personal bodies. People who embrace this view typically regard the body as a mere extrinsic tool that we may legitimately use to obtain desirable effects on our consciousness. (The consciousness is regarded by people who accept dualism as the “true” person who inhabits, or is somehow “associated with” the body.)
Bloom rightly states that the question of when human life begins is colored by one’s view of what a human being is. This is why, he says, people often appeal to science to answer the question “When does human life begin?” But this question, Bloom contends, is not really about life in the biological sense, but about “the magical moment at which a cluster of cells becomes more than a mere physical thing. It is a question about the soul.” Bloom says that science cannot answer this question because science has in fact demonstrated that “the qualities of mental life we associate with souls are purely corporeal; they emerge from biochemical processes in the brain.” According to Bloom, “this is starkly demonstrated in cases in which damage to the brain wipes out capacities as central to our humanity as memory, self-control and decision-making.”
On this point we believe Bloom is gravely mistaken. First, Bloom’s “stark demonstration” is no demonstration at all; it rests on what is manifestly a non sequitur. Shutting off action X prevents action Y: This shows either that X is identical with Y, or that, though X and Y are distinct, Y depends on X to occur. Severe brain damage prevents conceptual thought and decision-making–this much the medieval Christian philosopher and theologian Thomas Aquinas recognized centuries ago, and the ancient Greek thinker Aristotle acknowledged centuries before that. But Aquinas’ and Aristotle’s view was that conceptual thought and decision-making in human beings depends on brain operations (to provide sense experience) even though they (for different reasons) held that conceptual thought and free choice are distinct and non-bodily operations. Bloom has presented no compelling argument for his materialism or for the “great conflict between science and religion” that he claims exists on the question of human nature.
Second, pace Bloom, if science did show that all human acts, including conceptual thought and free choice, are just physical processes, then science would provide answers to important moral questions. It would just provide different ones from those we have traditionally accepted. In particular, it would mean that the difference between human beings and other animals is only a superficial one instead of a radical difference in kind; and it would mean that human beings lack any special, intrinsic dignity worthy of full moral respect. Thus, it would undermine the norms that forbid killing and eating human beings as we kill and eat chickens, or treating them as beasts of burden as we do horses or oxen.
In fact, however, the empirical sciences themselves have nothing to say one way or the other about whether there is an aspect of human beings–such as the source of conceptual thought and free choice–that is not simply a material process or a by-product of material processes. And the empirical sciences have nothing directly to say–they cannot, given the limitations of their methods–about an intrinsic human dignity and what the basis of such dignity is. So there is no “great conflict” between religion and science with respect to psychology; that is a fiction invented by scientists wandering into the domain of philosophy. Of course, there are philosophers who defend materialism, and who argue intelligently with fellow philosophers who reject it. But the argument by which Bloom purports to “demonstrate” materialism is worthless.
Bloom’s contention that because science has established materialism it is therefore unable to determine when human life begins is curious. Actually, the opposite is more nearly the truth: If body-self dualism were true, then science could not answer that question. Bloom’s mistake here is in supposing that the idea that life begins at conception (in a way that can settle debates over abortion and embryo-destructive experimentation) is somehow tied to the idea that there must be a “magical moment” when a soulless body becomes ensouled: “There is no moment at which a soulless body becomes an ensouled one and so scientific research cannot provide objective answers to the questions that matter most to us.” This is confused.
It is true that (empirical) science cannot by itself settle the ethical issue concerning the moral worth of embryonic and fetal human life. But if it is true that every distinct, human individual has intrinsic dignity–a proposition that most Americans hold, and one for which we have offered philosophical arguments in other writings–then science, in particular embryology, can answer an important question, namely, when does a distinct human individual come to be? The answer provided unanimously by the standard texts in embryology is quite clear. As one text puts it: “Human development begins at fertilization when a male gamete or sperm (spermatozoon) unites with a female gamete or oocyte (ovum) to form a single cell–a zygote. This highly specialized, totipotent cell marked the beginning of each of us as a unique individual.” (Keith L. Moore and T.V.N. Persaud, The Developing Human: Clinically Oriented Embryology, 5th edition, 2003, p.16. The answer is confirmed by William J. Larsen, Essentials of Human Embryology (1998), Scott F. Gilbert Developmental Biology, 7th edition (2003), and Ronan O’Rahilly and Fabiola Muller, Human Embryology and Teratology, 3rd edition (2001)).
Bloom seems to be misled on this, ironically, by an implicit consciousness-body dualism. He evidently holds that there is nothing intrinsically valuable (as a subject of rights) until there is a functioning mind. But because he supposes that science has shown that the mind is material and gradually develops (in the womb) and emerges more generally by evolution, he concludes that it cannot be determined objectively exactly when there is something of intrinsic value. However, what is intrinsically valuable is not the mental functions or qualities we have, but the being, the substantial entity, that you and I are. (By “substantial entity” we are denoting the thing that one is rather than the characteristics or properties inhering in one.) You and I are intrinsically valuable and equal in fundamental worth and dignity in virtue of what we are, not in virtue of qualities we may (if all goes well) acquire at some time during our lives–qualities that come and go, and which some human beings possess in greater degree than others. And so we are intrinsically valuable in a way that makes us possessors of dignity and bearers of rights from the point at which we come to be, and we remain possessors of dignity and bearers of rights until we die. Since dualism is mistaken–since we are not consciousnesses-inhabiting bodies but physical organisms possessing from the beginning a human (i.e., rational) nature–it follows that we come to be when our physical organism comes to be. And the science of embryology does determine when that occurs–namely, conception.
Finally, Bloom seems to have rushed to an acceptance of materialism because he erroneously supposes that if dualism is false then materialism must be true. He seems to assume that dualism and materialism exhaust the alternatives: Either we are souls that possess or inhabit our bodies, or everything in us is completely explainable by matter and material processes. But there is a third possibility, one that avoids the problems associated with dualism and materialism.
On one hand, a human being is essentially a physical organism, an animal. This point is shown (though the full argument would require more space than we have) by the fact that you and I–not any entities we merely possess or inhabit–perform and undergo bodily actions. Sensation and perception are clearly bodily activities, being performed with bodily organs such as sense organs and parts of the brain. So the subject that senses and perceives is a bodily entity, an animal-organism. But it must be the same subject, the same I, that senses or perceives and engages in conceptual thought (though conceptual thought is not itself a bodily action–more on this in a moment). It must be the same subject that perceives the ink marks on a page, for example, and understands the intelligible message contained in or signified by them.
On the other hand, conceptual thought and free choice are actions that cannot be material actions; that is, they are spiritual or non-material actions. An indication of this (though the full argument would need to be much longer of course) is that the term of conceptual thought is a universal content or feature (for example, what an animal is, as opposed to this or that particular animal), a feature not of itself restricted to a particular place or time. But every material action has as its term or object an entity that is restricted to a particular place and time. Hence there is an aspect of us, a capacity or power, which is non-material.
But this immaterial aspect is not the whole self, only an aspect or part of the self. On one hand, then, one can hold that the human being is not a soul alone, but the whole living bodily entity, a composite of body (or matter) and soul (the “form” or organizing principle of the living thing). On the other hand, there is an aspect of the human being that is non-material, and could not have emerged from matter and material forces. So neither self-body dualism nor materialism is correct. We are essentially physical organisms, and so we come to be when these organisms come to be–at conception. But we are also more than just the latest product of blind evolution, since there is an immaterial aspect of us that could not have emerged from lower material forces.
The “third alternative” we have outlined here is hardly an invention of ours. In one variant or another, it has been held by many of the most distinguished philosophers in history, and many hold it today. Moreover, it has been fully accepted by some religious traditions, including the world’s largest religious body, the Catholic Church. The Church rejects materialism and self-body dualism. The human being is neither a mere material reality nor a soul or consciousness possessing or inhabiting a body. As Aristotle recognized, and as many Christians and others have understood for centuries, the human being is a rational animal–an integrated unity of body and soul.
–Patrick Lee is associate professor of philosophy at the Franciscan University of Steubenville. Robert P. George is McCormick Professor of Jurisprudence and director of the James Madison Program at Princeton University.