I started the semester off in my applied ethics class with a unit on abortion, so I've been thinking a lot about arguments in the abortion literature that you don't often see at the popular level. I haven't taught this subject since fall 2004, so I'm sort of coming at a lot of this from a fresh perspective and rethinking a lot of the arguments I've been familiar with. Several things have occurred to me that seemed worth blogging about, so you can look for several posts on abortion in the next week or so as I write up my thoughts on some of these things.
One highly-anthologized article on abortion is Don Marquis' "Why Abortion Is Immoral". Marquis sets out to explain why abortion is immoral without assuming the personhood of the fetus. He instead develops an account of why killing in general is wrong. Killing is wrong, says Marquis, not because of some intrinsic property of the thing being killed (e.g. its capacity to feel pain, its consciousness, its ability to plan for the future, its self-concept, and so on), but because of the future it would otherwise have or be likely to have if you don't kill it. The reason it would be wrong to kill me is because of what you're taking away from me if you do so -- my future. The reason it's wrong to kill anything is because of the future you're robbing it of.
Now it follows that you're robbing a fetus of a future, and the future you're robbing it of is one like the future you and I have. You're even robbing it of more of a future, since it won't even get what you and I have already had that's now in our past. So abortion is wrong because it robs a fetus of a future like ours. This is so even if a fetus isn't a person. It has moral status not because of its current properties but because of what you would be taking away from it if you do certain things to it. In other words, its future (or what would otherwise be its future) is what guarantees the wrongness of killing it (and what you might derivatively call its right to life, but this is now being framed in very different terms.
That's the primary argument of Marquis' article. He doesn't spend much time developing it. Most of his effort goes toward motivating his theory of why killing is wrong and explaining why it's superior to person-based accounts. In this post, I'm not going to focus in on whether his theory of killing is correct, but I do want to flag a part of his support for it that strikes me as question-begging or at least as only appealing to a relatively small subset of potential readers.
One of the features he presents for his view on why killing is wrong is that it gives the right results about a number of other issues. Philosophers often give such arguments. They present a theory about something, and then they point out that their theory fits nicely with people's intuitions about other matters, and the alternative theories they're considering conflict with those same intuitions. The problem in Marquis' use of this strategy is that he chooses some controversial intuitions, indeed a pretty strange combination of them.