Note: I wrote this blog post originally at Walking Christian. I re-read it and thought it was pretty good and I wanted to post it here too.
This is probably one of my favorite topics to discuss and debate. I’ve got a lot to learn, but I feel like I’m fairly competent in discussing this issue and giving a good pro-life case. I think one of the huge points of confusion in this debate comes when using terms such as human being, human nature, personhood, humanity, and human organism. These words have very different meanings in different contexts and this only asks for an equivocation to occur. Hence why I think defining one’s terms and usage of them before ever debating the issue is extremely crucial. Otherwise, you’ll just be tripping over your words and making a mess everywhere.
Personally, I hate treating personhood as if it’s some deciding factor for an individual to be counted as a person. See, my language already is assuming that there are human beings that are not persons, and this, I think, is problematic. Sadly, the philosophical community has assumed that a “person” is just a collection of traits that make one valuable. So, what I want to do is define my terms and proceed to explain my case for the pro-life position using thomistic language and metaphysics. In doing so, I will demonstrate why I have such a problem with this divide over personhood. Moreover, by using a Thomistic metaphysics, I will try and show that this “personhood” issue isn’t really an issue at all.
The basic idea
First of all, I think it’s fairly plausible, if not blatantly a fact, to say that at a biological level we are a human organism. Now, I’d like to state that I equate being a human being with having a human nature or essence, and a human nature belongs with that substance that is human, i.e., a human organism. There is a substance (the human organism), that has a nature (human nature), and this nature is what makes the organism what it is, namely, a human being. So the terms human being and human organism will be used synonymously to simply mean that which is a member of the species homo sapien.
From the get go, metaphysically speaking, a human organism is what it is because it has a human nature, and these cannot be separated. You cannot have a human organism that does not have a human nature because then the organism would not be human. Having a human nature, then, is a necessary condition of being a human organism. Therefore, one can say that a biological human organism is a human being.
To quickly switch gears, I’d like to illustrate the basic pro-life argument.
The basic argument is this:
1. It is wrong to intentionally kill an innocent human being.
2. A fetus is an innocent human being.
.’. It is wrong to intentionally kill a fetus.
I first want to deflect a common objection that the first and second premise are equivocating and thus the argument commits a basic fallacy. The conclusion doesn’t follow, according to this objection, because the meaning of the word “human being” changes within the first and second premise. The first premise would be true if by human being one means a person. This premise assumes a moral use of the term “human being,” as Mary Anne Warren points out. That’s all find and dandy. But the supposed equivocation occurs in premise two. Bear in mind that the assumption behind the objection is that personhood is the morally relevant criteria. If the term “human being” in premise two means a “person,” then the argument would be valid but unsound due to this premise being false, according to the objector. But if the term “human being” in this premise means a member of the species homo sapien, then the premise equivocates terms and is thus invalid. The reason is that being a member of the species homo sapien is not sufficient for personhood since you can have humans that are not persons. What’s relevant is personhood and one has not distinguished whether one means “human being” to mean a member of the species homo sapien or personhood. As I will argue later on, the personhood criteria is heavily flawed, and a human organism by nature of what it is is entitled to rights and moral status thus avoiding the problem entirely since being a member of the species homo sapien is sufficient for moral status. (Note that I have argued for this here.)
When does a human being come into existence?
To further add to this idea of a human being, my basic argument is taken from what Oderberg calls the “argument from continuity of development.” This will also lead us to answer the question of “When does a human being come into existence?” The argument, as Oderberg explains, is “that there is no metaphysically significant dividing line in embryonic and foetal development separating something that is a human being from something that is not; hence the embryo/foetus is a human being from conception onwards” (8). Oderberg elsewhere notes that the argument is about the “identity of the foetus — is it the very same thing throughout its development? More precisely, is it the same human being as the baby/child/adult into which it develops?” (12). This is the type of premise that the “I was once a fetus” argument is based on. The basic idea goes like this: I was once a fetus. I am the same person I was then. If I were to look at a photograph of me that was taken 2 weeks ago, I would be justified in claiming that that’s me. I could say the same of a picture taken 10 years ago of me. I could also say the same thing of a picture taken when I was 2 years old. I could also say the same thing of an ultrasound taken of me at 2 weeks old. That fetus is me. If I have rights now, then I had rights then. If it’s true that the fetus retains its identity throughout his/her(its? I don’t know what the politically correct term is), then the correct way to view the developing fetus is to see it on a continuum. If this is all true, then the answer to the question “When does a human come into existence?” is from the moment of conception.
Now, to address this issue of personhood and when a fetus “gains personhood”, I’ll turn to the concepts of act and potency which is derived from Aristotle’s philosophy. To say something is in “act” or to be actual is to describe the way something is. Feser, for example, uses a rubber ball to demonstrate this. He explains how “among [the ball’s] features are the ways it actually is: solid, round, red, and bouncy. These are different aspects of its ‘being’” (Feser 10). Potency is the way a thing potentially is. To continue Feser’s example a ball is potentially green or black if you were to paint it and it is potentially “gooey (if you melt it)” (Feser 10).
But potency just doesn’t mean a thing in actuality can possibly do anything or become anything. For something to be potential it means that the substance has these potencies built into it. Edward Feser explains it this way, “The potentialities Aristotle and Aquinas have in mind are ones rooted in a thing’s nature as it actually exists” ( Feser 11). So, while I have the potential to grow another 5 feet tall, I don’t have the potential to become a werewolf. The latter is not a potency that is a part of my nature. So potential is always inherent in the thing that is.
To take another example, a piece of chopped up wood cannot potentially be a steel ship. Why? First because the steel is an entirely different substance. The wood cannot change or become something that it does not have. To use a common sense example, I cannot give you what I do not have. The wood, however, has the potential to become a house, or an axe handle, or a wall, or even part of the steel ship in terms of the ship having wooden floors or doors. These things are potentialities that the wood can fulfill since its nature allows it to do so. But the wood cannot become the steel.
Now with these distinctions in place, I turn to the personhood issue and the properties that go along with it, the properties such as rationality, consciousness, self-awareness, volition, will, etc.
I’ve heard it said that a fetus might be biologically human, but it doesn’t have rationally or self-consciousness and thus doesn’t count as human. Already we have a problem here. The metaphysic is off and the assumption is that a human organism becomes a human being when it acquires some property such as rationality or self-consciousness (the common ones that are appealed to). First, I think we have plausible grounds to accept the metaphysic I’ve proposed. Scientifically we see that a human organism, from conception, if nourished properly and if it develops normally, it becomes a fully grown human organism with fully functional mental capacities. I think the substance view of human beings is quite possible. A thing or substance(human organism) contains a nature (human nature) that allows it to grow and develop into a fully functional thing (human being).
When a fetus grows into a baby, and a baby into a toddler, and the toddler into a child, why doesn’t the child gain some other property like non-rationality? Why does the child gain the property of rationality? This seems like a dull question to ask but I think it’s one that must be asked. Why doesn’t the child develop into a log cabin? Why not the property of having a butterfly mind? I think it’s very plausible to posit the answer to this as being because rationality moves from potential to actual, and potentiality can only exist in the thing itself, that is a human substance or organism. These properties that were named earlier (rationality, self-awareness, consciousness, etc.) are actualized or gained precisely because they are potential in the substance itself. The human organism contains these properties in a state of potency, and thus they are always in the substance just waiting to be actualized. So it’s wrongheaded to try and divorce these states and say that the fetus is not human because it doesn’t have these properties actualized when the fact of the matter is these properties can only be actualized if the substance is human in the first place!
Personhood doesn’t even become an issue because, as I said earlier, personhood is inherent in the nature of a human, and during development, its properties of rationality, consciousness, and awareness is in a state of potency. Given enough time and the proper nourishment, this fetus would continue its natural development and these properties will inevitably be actualized. It’s like me grabbing the bag of popcorn kernels form my cupboard and throwing them all away. “What in the world are you doing?!” My mother screams. “This isn’t popcorn so what’s the point of having it?” I respond. “You have to heat them up. It is popcorn, you just have to let them fully develop. They’re popcorn kernels. Not apple seeds or orange seeds. But popcorn kernels.” I think a more telling action would be for me to grab the kernels out of the microwave while it’s heating up and just to throw them away since they’re not “fully popcorn”. My actions would be plain stupid and absurd. Similarly, to just abort the fetus because it hasn’t developed its rationality (or any of the other properties) is equally stupid and absurd.
The rationalization that a fetus can be aborted because it doesn’t contain personhood is completely off chart and I’ll go as far as say it’s utterly absurd. We accept our humanity yet we deny our humanity on the basis that some do not have the properties we have simply because they weren’t given the time of day to develop them. I fail to see any intellectual viability with those who are in favor of abortion. So far my arguments have gone to show premise 2 to be more plausibly true than false, and I’ve simply assumed that we all are moral realists and agree with premise 1 in that it’s wrong to kill an innocent human being. I welcome any dialogue and I look forward to it. In the mean time, popcorn anyone?
 Oderberg, David. Applied Ethics: A Non-Consequentialist Approach. Blackwell, 2005. Print.
 Feser, Edward. Aquinas: a beginner’s guide. Oxford: Oneworld, 2009. Print.