The Review’s editorial last week concerning Ohio’s “Heartbeat Bill,” a proposed ban on abortion after a fetus’s heartbeat can be detected, rightly condemns the legislation as dangerous and wrongheaded. However, like the majority of arguments put forth by the “pro-choice” camp, it fails to directly engage with the “pro-life” claim that fetuses are morally equivalent to adult humans.

Most feminist writing on abortion seems to ignore or downplay the question of fetal rights, attempting to frame the issue as simply a question of women’s rights. We hear, for example, that bans on abortion constitute an unacceptable restriction on women’s personal autonomy; the bumper sticker phrase “Keep your laws off my body” illustrates this view pretty well. However, viewing the issue as concerning nothing more than women’s autonomy makes no sense if the exercise of this autonomy infringes on the rights of another person — if your body happens to be punching someone else repeatedly in the kidney, the law is going to get all over it, and there aren’t many people on either side of the abortion debate who will find that unreasonable.

To help demonstrate the relevance of fetal rights to the abortion debate, I’ll borrow a particularly vivid thought experiment used by Judith J. Thomson in her essay “A Defense of Abortion.” Imagine that you have been kidnapped by the Society of Music Lovers and attached to an ailing violinist. The musician is dying of kidney failure, and if you remain attached to him for nine months, his kidneys will be healed and you will be able to go your separate ways. While it would be nice of you to sacrifice nine months of your life to save the violinist, you are by no means morally obligated to, and it is hard to imagine a society in which you would be required by law to do so. The important thing to note about this situation, though, is that you are not responsible for the violinist’s condition, and so this thought experiment can be used to successfully argue that, even if a fetus is a person, a woman has a right to an abortion in cases of rape. However, as long as we accept that a fetus does have the same right to life as anyone else, it is difficult, if not impossible, to see how abortion could be morally permissible outside of this extreme situation.

Suppose that a woman gets drunk at a party and has sex with a man, a decision she would not have made had she been sober, and which she immediately regrets upon awaking the next morning in a room covered with posters of Japanese cartoon pornography. Some time later, she finds that she has become pregnant, and wants to have an abortion.

How would this situation translate into our violinist thought experiment?

Imagine another woman becoming intoxicated at that same party, but, rather than going home with an anime porn enthusiast, unwisely climbs into her Winnebago and takes it on a joyride through Oberlin. Her adventure ends in tragedy when her vast recreational vehicle leaves the road and plows down a violinist as he is exiting Finney. When she regains consciousness, she finds herself attached to the violinist; apparently the only way he can survive his Winnebago-inflicted injuries is to remain connected to her for the next nine months. Is it morally permissible for this woman to detach herself from the violinist, thereby causing his death? Certainly not. She bears responsibility for placing him in this situation, and the fact that she would have acted differently had she not been intoxicated does nothing to absolve her of this responsibility.

Denying the Winnebago driver the right to kill the violinist seems altogether reasonable, but it strikes me as completely unreasonable to deny an abortion to the woman in the previous case. So what’s the morally significant difference between a violinist and a fetus? The violinist is a self-aware agent, capable of a vast possible range of happiness or suffering, with his own fears and aspirations — the fetus is not. This distinction, or something very similar, is what separates something that is a person from something that is not, and is the rational basis for denying the fetus the same moral consideration we owe to the violinist.

The most obvious problem that this view raises is the fact that newborn babies don’t have the morally important properties described above. How, then, can we square this view with our intuition that it would be wrong for people to go around euthanizing babies all the time? There’s a lot to be said on this point, but for now, I’ll just observe that self-awareness doesn’t spring suddenly into existence, and so there won’t be any clear line that can be drawn to indicate the point at which a non-person becomes a person. In utero fetuses are unambiguously not people, however, so the time of birth (or the point at which the baby could safely survive outside of the womb) seems like a safe enough place to draw the line.