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Conscience Magazine

Destined to Be a Person? Thomas Aquinas and Fetal Personhood

By Daniel A. Dombrowski September 12, 2014

BR-aquinas-cover-amerini-henningerHominization, or the point at which the fetus becomes a person, is a subject of vital importance in public policy, where one hears definitive claims about fetal personhood at the point of conception used in opposition to abortion, emergency contraception and stem cell research, to name a few. Sometimes these voices are Catholic, though they may be surprised to learn that the Vatican has never definitively declared the point at which a fetus becomes a person. Fabrizio Amerini’s book examines one of Catholicism’s most-revered thinkers, St. Thomas Aquinas, whose 13th-century ideas about the beginning of personhood challenge some of the assertions frequently made by today’s Catholic hierarchy.

The church’s opposition to abortion is based on a position called “immediate hominization,” which means that the fetus is a human person worthy of moral respect from the “moment” of conception. But Thomas Aquinas defends a view called “delayed hominization,” which means that a fetus could not be a human person until it has a body that is developed enough to make possible rational thought—say, through the development of a brain. Amerini, professor in the Department of Classics, Languages, Education and Philosophy at the University of Parma, could also have found a similar challenge from the second leading Catholic thinker, St. Augustine, whose life spanned the 4th and 5th centuries and whose work also defends the idea that the fetus was not immediately a person.

Amerini’s book is the most detailed and evenhanded treatment of this Thomist discrepancy to date. But despite its considerable intellectual strengths, it is a frustrating book to read, particularly at the end, where the implications of Aquinas’ thought for the contemporary abortion debate are considered.

Aquinas’ belief in delayed hominization is compatible with a prochoice stance that would morally permit abortion, as Amerini admits. If one holds that the fetus in the early stages of pregnancy is not a human person precisely because it is only a potential human person, then it makes sense to deny that abortion and voluntary homicide are morally equivalent.

But Aquinas’ view is also compatible, Amerini thinks, with a stance against abortion when the timing of hominization is set aside. Fetuses are transitory entities in Aquinas’ thought, moving from a vegetative state to a sentient one and then eventually to a state that provides the material preconditions for rationality. But Amerini holds that the embryo is, right from its conception, “in the process of becoming a human being.” That is, according to his interpretation of Aquinas, the fetus is not yet a human person, but it is in the process of becoming one.

The inference is that the end result of this fetal development—into a human being—tinges every previous stage all the way back to the embryo itself. Examining the ultimate ends of the universe by natural design is classic Thomas Aquinas, whose “Argument from Design” or “Teleological Argument” held that natural processes could be explained by their directive principles. The 13th-century Catholic thinker’s views on delayed hominization are built on what could be termed fetal teleology—along the lines of asserting that a human fetus cannot develop into a full-grown horse because such an end is contrary to its nature. But his modern-day student, Amerini, conflates a potential person with a person-in-process whom, he asserts, should be treated as a person.

Readers of Conscience should be wary of the way in which Amerini transforms the step-by-step assertions of Aquinas’ lowercase “t” teleology into Teleology with an uppercase “T”—the idea that treatment of the fetus at all stages should be based upon an unknowable future. The potential for X does not mean that one actually has the rights and privileges associated with X—otherwise one could make the absurd demand that one’s potential to be president of the United States warrants the playing of “Hail to the Chief” every time one enters the room. Or again, when a .333 hitter in baseball enters the batter’s box, it is not definite that he or she will get a hit; there is only a one-third chance that this will happen.

One might ask the question: why be opposed to abortion, at least in the early stages of pregnancy, if one is a delayed hominization theorist? Amerini’s answer is that even the early fetus is “destined” to become a human person, such that were it not for a humanly induced abortion, the fetus “will later actually be” a human person. This is because the process of generation during pregnancy “will lead” a fetus to become a human person, so “of course” even the early fetus should be protected.

This sort of language on Amerini’s part strikes me as inaccurate. It is inaccurate because it seems to violate the asymmetrical character of time. We adults can know that we were once fetuses, but no early fetus can know that it will become a human person, nor can anyone else know this. It should be noted that less than one-third of conceptions are eventually born as infants—quite apart from humanly induced abortions. That is, nature performs abortions at a much higher rate than any human society.

As a result, it would be more accurate for Amerini to say that it is possible (not even probable, much less destined) for a very early fetus to become a human person, that it might become a moral patient worthy of respect, and that the process of generation during pregnancy could result in a human person—not that it should or will result in a human person.

Amerini is surely correct to claim, along with Aquinas, that there is a sort of numerical identity between the fetus and an adult human being. Each one of us was once a fetus, and it makes some sense to say that I am the same being who started as a fetus so many years ago. But it also makes sense to say that I am a quite different being from the one that was once a fetus. It is not merely that I am older than I was when I was a fetus. Rather, I am, in a certain sense, a quite different being, because now I am at least intermittently rational, capable of self-consciousness, sometimes sympathetic to the sufferings of others, etc., whereas as a fetus, I was actually none of these.

In summary, Amerini does a meticulous job of detailing both Aquinas’ delayed hominization view and the ways in which this stance is at odds with the institutional Catholic church’s current position on abortion.

Amerini’s book is a magisterial piece of scholarship, and readers should appreciate that such a book, published by a highly respected academic press, contains the idea that Aquinas’ view of delayed hominization is compatible with a prochoice stance. But this concept is only mentioned briefly by the author and is not developed in any detail. His sympathies clearly lie with the antiabortion view. Although he is quite explicit that Aquinas’ delayed hominization view is at odds with the current official view of the Catholic hierarchy, Amerini tries as hard as possible to reconcile this aspect of Aquinas’ work with later Catholic teachings against abortion. It would have been a more parsimonious exercise to simply criticize the hierarchy’s current position using one of their foremost Catholic thinkers as a pivotal point.

Aquinas on the Beginning and End of Human Life
Fabrizio Amerini; translated by Mark Henninger
(Harvard University Press, 2013, 260 pp)
978-0674072473, $29.95

Daniel A. Dombrowski
Daniel A. Dombrowski

is professor of philosophy at Seattle University, as well as the chair of the Catholics for Choice Board of Directors. His publications include coauthoring the book A Brief, Liberal, Catholic Defense of Abortion.

Tagged Abortion