Yesterday, I said that there is a particular way of arguing for the full humanity of the unborn child that is problematic. I mentioned the philosophic problem of heaps. If you weren't listening, I'll give it to you very quickly.

You can have a pile and you can have a heap. A pile is like a couple of things, like maybe fifteen or twenty seeds. Then you have a billion seeds over here, making a giant mound or a heap. So you have this little bitty pile and you have this big giant heap. Now the question is--and this is the problem of heaps--can you make a pile into a heap by adding one seed? That seems silly. But the fact is, if you keep adding seeds to your pile, it gets bigger and bigger. At some point, by adding one seed, it ceases to be a pile and it becomes a heap. But you don't know when that happens. You know there is one little pile and one big giant heap, but when you talk about the gradual addition of seeds to your pile, it isn't really clear when it becomes a heap. However, just because we can't tell where one thing changes from one kind of thing into another kind of thing--where the pile turns into the heap--doesn't mean there is no meaningful distinction between the pile on one hand and the heap on the other. You don't always have to be able to show where it crosses the line in order to prove there is a difference.

This has been a problem for pro-lifers when arguing for the full humanity of the unborn child. They might say there is a gradual continuum of development from the fertilization of the egg and the introduction of the zygote--which is the separate individual being--that then begins to grow. There is a continuity until birth. Most of those who think that abortion should be legal would concede that you have a human being at birth, but would say that you don't at the zygote stage. The pro-lifer would argue there is a continuum of development and you can't pinpoint when it crosses from a non-human into a human and, therefore, you can't assert that the about-to-be-born child is really different from the zygote.

The pro-choice person can turn around and say, "You know, I don't know what happens in the second trimester. I know a third trimester child is a child. A first trimester one isn't. Just look at it, it's obvious. Because I can't show the precise transition in the middle, it doesn't mean that I am not justified in identifying a difference between a zygote and a full-term child." That is the argument, you see, and this is what I mentioned yesterday. That's how the problem of heaps applies to this issue and how pro-lifers can be compromised if they are from the continuity of life. It's also why I said yesterday that we ought to use a different kind of argument.

That is what I was wrong about and it's what I'm going to correct. I don't think the problem of heaps compromises our view of the continuum of life. This will be an opportunity for exploration about the nature, in the technical sense, of the unborn child.

The key is whether heaps and piles are representative of the development of an unborn child. I don't think they are. In the case of heaps, what we have are groups of things. We have bunches of seeds and as you add more seeds to the bunch, this aggregate changes as we increase the numbers of seeds. So, if we have two human beings, that's a couple. But when we add one more human being, the couple disappears and it becomes a trio. We add one more, and the trio disappears and we have a quartet. By just adding numbers to these things, it actually changes what it is. A duet changes to a trio which changes to a quartet by merely adding physical things.

The only thing that changes at birth is the child's location. ... Change of location is not a relevant change to change the very identity of a thing.

I did a commentary on the radio called " Wouldn't I Still Be Me? " My argument was, wouldn't a person still be themselves even if you started whittling parts off their body? Wouldn't they still be themselves even if they lost physical capabilities like sight, or maybe IQ, or the ability to reflect? They'd still be what they are, wouldn't they? That's the case with human beings.

I'm going to prove this is true by saying you already believe it. You believe that human beings are the kind of beings that sustain identity through change. All living beings are like that, by the way. Physical things, like heaps, aren't. But living things sustain identity through change. How do I know that? Because you celebrate your birthday. (What's that got to do with it?) Well, the fact is, if you are 49 years old, your body has changed completely seven times over since the time you were born. Every seven years you replace almost every cell in your body with a new cell. Same pattern, different cell. Which means, you are seven times removed from the same body that you had when you were born. But you are still you, right? The body you had shows that you are different from the body you currently possess. You possess the body, you aren't the body. You celebrate your birthday because you have sustained your identity through the change of your physical body.

Here's another reason. You believe in justice. We had a big trial recently. Some people didn't like the way it went. O.J. Simpson was on trial for one reason, because he sustained identity through change. If he didn't sustain identity through change, we could never try him for a murder that was committed by some person who couldn't even in principle be the same body that he now has, because all bodies have changed over the last two years. What is it that stays the same through all this physical change? The person O.J. himself. What this teaches us is that human beings at least, and I would think all living beings, are the kinds of beings that sustain identity through change.

I talked with Bill on Friday and Bill didn't like this argument at all. He argued that an acorn is not an oak tree. I said "You are right, but both are oaks. The oak has an acorn stage, then it develops into a seedling stage, then a sapling stage, then a tree stage and then a great oak stage. All are different stages in its development, but it always is what it is. It is always an oak, represented as an acorn, as a seedling, as a sapling, as a great oak at different times. But it still is what it is."

If it seems to make sense for you to say, "Yes, I was once an unborn child," or even "I once was a zygote," that points out that you, the one you are, the person you are, existed then and one would have to identify a meaningful juncture of change to show otherwise. Bill, who denied my thesis, would have had to say that he didn't exist before he was born, and he came into existence when he was born. But my question is, is birth a meaningful juncture in identity change such that the body that was developing wasn't him and then it became him at birth? My answer is, no, it simply is not a meaningful juncture. The only thing that changes at birth is the child's location. It is inside the mother, then it moves outside of the mother. That's the only thing that changes. Change of location is not a relevant change to change the very identity of a thing.

I believe that the problem of heaps doesn't apply to this issue because a human being is not a heap. It is not an aggregate thing. It is a living being who sustains identity through change and therefore the continuum argument can be made.