Wednesday, June 29, 2011

Deductive reasoning and the pro-life argument: Part Two

Who am I?
I recently presented five different formulations of a deductively valid argument for the pro-life conclusion that elective abortion is morally wrong. Here are two more that deal explicitly with the question of personal identity.

Philosopher Alexander Pruss offers the following:

1. "I was once a fetus."

This premise "seems innocuous," Pruss writes. "After all, is it not biologically evident that first I was an embryo, then a fetus, then a neonate, then an infant, then a toddler, then a child, then an adolescent, and then an adult? Does not my mother talk of the time when she was 'pregnant with me' and thereby imply that it was I who was in her womb when she was pregnant? Is not the sonogram of my daughter the sonogram of that daughter of mine who will be born?" Pruss defends this position well in his essay.

2. "If I was a fetus, it would have been wrong to kill that fetus."

Pruss reasons (among two other arguments he offers for premise 2): "What would make killing me now wrong is the harm it would do to me: it would deprive me, who am juridically innocent, of life, indeed of the rest of my life. Now, consider the hypothetical killing of the fetus I once was. This killing would have exactly the same victim as killing me now would [as demonstrated by premise 1]. Moreover, the harm inflicted on the victim would have been strictly greater [because the victim is deprived of more of his life when he is killed at a younger age]." What makes killing me now wrong also makes killing the fetus I once was wrong.

3. "If it was wrong to kill me when I was a fetus, it is wrong to kill anyone when he is a fetus."

Thus, killing unborn human beings is wrong. See more thoughts on abortion from Pruss here.

In a section of his recent book The Ethics of Abortion (pp. 105-120), philosopher Christopher Kaczor proposes this "constitutive property" argument for the personhood of the unborn:

1. "If an individual being has a constitutive [i.e., essential] property at one point in time, then it has that property at every point in its existence."

This is true by the definition of "constitutive property."

2. "You are the same individual living being or organism as the fetus from which you developed."

This is identical to Premise 1 in the argument above. Kaczor notes that the truth of this premise seems to be "a matter of observation and scientific data. You now, you at ten years old, you at ten days following birth, you ten days after conception and you at all stages of your life in between stand in bodily continuity."

There are different approaches to denying a continuity of personal identity throughout the life of a human being -- some of a weird dualist variety, some reflecting a radical commitment to philosophical materialism -- but all are untenable. Detailed critiques are presented in Body & Soul: Human Nature and the Crisis in Ethics by J.P. Moreland and Scott Rae, Abortion & Unborn Human Life by Patrick Lee (Chapter 1), and Embryo: A Defense of Human Life by Robert George and Christopher Tollefsen (Chapter 3). See also Kaczor's critique (pp. 106-115). (These authors do not all agree about the metaphysical details; the key point is simply that there is a continuity of personal identity -- what Francis Beckwith calls the substance view of persons.)

3. "You are a human person constitutively [i.e., essentially]."

That is, each of us has the moral status of a "person" (entailing a right to life) simply by virtue of being who/what we are. It is not a status that we can gain or lose, but something that exists as long as we exist. This is roughly equivalent to Premise 2 of the argument above.

4. "The zygote from which you developed was a human person."

Another way to put the argument is this: We have a right to life by virtue of what we are (premise 3); what we are came to be at conception (premise 2); so we had a right to life from conception.

In both of the two arguments, the point is to show that (1) there is a continuity of personal identity throughout the life of a human being (e.g., I am identical to the fetus, infant, and adolescent I once was, despite growth and change); and (2) it is by virtue of our identity (the kind of being we are, not what we can do or other non-essential characteristics) that we have full moral worth/personhood/a right to life. (For defenses of point #2, see my earlier post.)

These are common-sense views that are philosophically much more plausible than their alternatives, and they lead directly to the conclusion that the fetus I once was had a right to life, and by extension, all human fetuses have a right to life, which clearly precludes intentional killing for the reasons for which elective abortions are performed.

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