Hello all,
So what are some philosophical arguments for the personhood of the fetus? Peter Kreeft makes some good points in his
Apple Argument against abortion and another article he wrote strictly about
fetal personhood. However, Kreeft stops his argument just short of being completely convince-able. One thing I’ve heard in my research is that all humans are persons but not all persons are humans, however this is hard to prove philosophically.
Back to my original question: how can fetal personhood be proven?
Dear Coolduude,
The personhood of a fetus or embryo can be argued from philosophy, but in order to do so, it is best to begin by defining the terms correctly.
So, the first question is, “What is a person?” and there is a related question, “How can I tell if what I have before me is a person?” It seems to be a habit of contemporary philosophy to define personhood based on what people
do, and not based on
who they are; for example, by defining “person” as “someone who is capable of relating to others” or “someone who is able to make ethical decisions.” The problem is that, if the capacity in question is somehow impeded (for example, if the subject goes into a coma, or else suffers from mental retardation, or even when he goes to sleep at night), then it seems as if personhood is also impeded.
Therefore, it is better to go the rout of a definition according to
being, not accoding to
doing. I don’t think we get any better than the classical definition given by the 6th-century Christian philosopher Boethius: a person is an “individual substance with a rational nature.” (St. Thomas Aquinas refines it further, but Boethius’ definition will suffice for our purposes. You can find it in Boethius’ work
On the Person and Two Natures.)
Some parsing of philosophical terms is in order here. “Substance” is the classical philosophical term for those beings that exist in themselves and not in another being. (For example, a banana is a substance, but the yellowness of that banana does not have an independent existence; it is an “accident.” The fruit exists by itself; the color only exists
in the fruit. In this sense, a human being is also a substance: he has an independent exisitence, although, of course, he has a much greater dignity than a banana.) In some philosophical contexts, “substance” can refer, not to concrete realities, but to abstract ones, and so Boethius insists that the term “person” always refers to an
individual: a concrete reality, not an abstraction.
The key idea, however, is that a person is a reality with a
rational nature. Behind this idea is a conception of how all concrete realities–all substances–are structured: substances undergo all sorts of changes without ceasing to be what they are. For example, I started out as an embryo, and then grew into a fetus, then became a baby, then a toddler, and so on, until I reached adulthood. In that process, I underwent a lot of external changes, but I remained the same individual. The aspect that remains the same philosophers call “essence” or “nature:” it is the principle that makes something what it is. It is very important to distinguish between nature (what something
is) and its
effects (what that thing
does), because the effects come and go, but the nature remains.
A person, then, has a nature, and what is more, a
rational nature: in other words, it has, by its very nature, a fundamental capacity for intellectual activity. Boethius is not here reducing human nature to its rationality, but he is using that rationality as an indicator of something deeper: that a human being is a
spiritual being, not simply material.
What I said about the structure of all substances–that each one is composed of a stable principle (essence or nature) and a changable principle (usually called “accident” or sometimes “operation” by philosophers)–can help us answer the second question: “How can I know if the thing I have before me is a person?”
No one disputes, I think, that a full grown human being is a person. It would follow that he must have a rational (that is spiritual) nature, and this seems to be born out by experience. The question then becomes, “When did he start to have a rational nature?”
Accidental changes, as we saw, are not enough to change the nature. It
is possible to make “accidental changes” in material beings that are so extreme that the substance in question cannot survive. Philosophers call this “substantial change;” in this case, it is not so much that that the nature
changes, so much that it goes out of existence (at least as regards the material entity in question). This happens, for example, at the death of a living being (even for human beings): the body left behind after death is can no longer be identified with the being to whom it once belonged.
It is important to note that “substantial” changes are inherently instantaneous and irreversible: it may be difficult to determine the moment of death, for example, but that does not take away from the fact that the death actually happens in a given, precise instant: on the day that I make my encounter with the Lord, I won’t be “partly alive” and “partly dead.” No: when the moment arrives, I will undoubtedly be weak, and my vital signs will be failing, but I will pass at one given moment from being “alive” (albeit weak) to being “dead,” without any intermediate stages.
Some “accidental” changes are sudden, too. (Supercooled water, for example, freezes quite dramatically if you add ice to it.) However, all
gradual changes must be accidental (because, as we saw, all substantial changes are sudden). That includes, for example, the development of animal or human being from childhood.
With these concepts in mind, let’s try a thought experiment. Do I (an adult human being) have a rational nature now? Yes. (I hope!) Did I have one when I was a child? Yes, because all developmental the changes I have undergone since then have been gradual and continuous. Did I have a rational nature when I was a baby? Yes, because my development from infancy to childhood was perfectly continuous. What about the day before I was born? Yes, for the same reason: my passage through the birth canal did nothing to affect my continuous development. What about three months before I was born, or six months? The same. What about when I was a zygote (the product of the fusion of sperm and oocyte)? The same. (Embryonic development is manifestly gradual and continuous from the moment of fertilization: you can verify that in any serious textbook on embryology.)
The conclusion is that, from the time I was a zygote until now, I have had a rational nature, and I will continue to have one until my death. (I will continue to have one even after that, but the arguments for that go beyond this topic.) Since persons are precisely individuals with rational natures, it follows that I have been a person continuously, ever since I was a zygote.
What about before I was zygote? No. The fusion of egg and sperm produces a true
substantial change, and so at that moment my life–and hence, as we saw, my personhood–began.
Can we apply this reasoning across the board to
all human embryos? Yes, absolutely, because human nature–understood this time as an abstract, universal, principle–pertains to
all members of the human species. (You can’t be
human without having a human
nature, because nature makes you what you are.) To put it another way, we know that a human zygote or embryo will necessarily develop into an adult human being, unless something impedes it. Just because something could impede its development does not take away from the fact that it
already possesses a human (and thus, rational) nature and, therefore, personhood.
The conclusion is that all individuals of the human species, regardless of the stage of development, and also regardless of factors that impede that development (such as mental retardation, etc.), are persons, with all the rights of persons, from their conception (fertilization) to their death. (They remain persons after their death, as I said, but they are at that point, of course, no longer subject to death.)
I don’t know if I expressed my reasoning clearly, or if I confused matters more. This is the argument that most convinced me of the personhood of human embryos, and I hope you found it helpful.
Incidentally, all human beings are persons (as this argument proves), but there are persons that are not human: angels and especially the Persons of the Trinity. In fact, Boethius made his definition in order to help theological reflection on the Trinity and on Christology. However, nothing
infra-human is a person: for example (non-human) animals are not persons.
God bless.
Bro. Louis.