By William H Stoddard
Among supporters of the right to abortion, many believe that that right weakens, or can be set aside, late in pregnancy. Sometimes this is based on viability, or the fetus's potential for surviving outside the uterus. Adherents of Ayn Rand's view of the rational faculty as the source of rights sometimes base a similar view on the emergence of brain activity late in pregnancy. I recently commented on this issue; I've been asked to present my comments on Politics without God for a wider readership.
In practical terms, I think this issue is nearly always moot. There are very few difficulties with a pregnancy that will first show up that late, and for a fetus that advanced, the risks of abortion are often comparable to those of birth.
However, as a matter of principle, I think it's mistaken.
We can say that I have a right to life partly because my life does not inherently impose costs on you. If you and I are in the same room, the carbon dioxide I exhale doesn't poison you, the heat I radiate doesn't burn you, and the hormones, allergens, or drugs in my bloodstream don't change your metabolism. Note, too, that if I am suffering from a contagious illness, a case can be made for forcibly restraining me from interacting with other people, and that case grows stronger as the illness grows more infectious and more lethal. This is precisely a situation in which my biological functions and yours are not fully separate when we are close together.
But a fetus and the woman carrying it cannot possibly have separate biological functions. Its oxygen and nutrition come from her blood; its wastes go into her blood; its presence alters her hormonal state and mechanically strains her body. And what she does affects it almost as much, though it has some insulation. Treating them as if they were two separate individual beings doesn't make sense, no matter how cognitively functional the fetus is. So talking about what rights the fetus has, as against what rights the pregnant woman has, is a kind of stolen concept: it attempts to apply the concept of individual rights when there are not two individuals.
And given that one nervous system is fully conscious and volitional, and the other is only beginning to be so, it has to be the woman who makes medical choices. Few women who have carried a fetus for 24 weeks are going to choose abortion at that point, and certainly not on impulse; but if the pregnancy turns life-threatening, I think it's justifiable for the woman to choose to have the fetus removed, just as she could choose to have a limb or an organ removed if the alternative were death from gangrene or cancer—also choices that a woman would likely find difficult and make with regret. And in any case, it's not possible to have the woman and the fetus vote on whose life should be saved, or to consult with the fetus; the woman has to decide. If she chooses to risk her life, or die, to give birth, that's her right; but the fetus can't have a right to demand that she do so, because it's not a separate individual and can't have rights. Life is a property of individual living organisms; if there aren't two fully separate organisms, there aren't two lives, and there can't be two separate (and potentially opposed) rights to life.
If we had different technological options, we might have to resolve other issues. The science fiction writer Lois McMaster Bujold writes about societies with "uterine replicators," which permit a fetus to develop outside it's mother's body; a fetus in a replicator seemingly would be a separate individual, as much as a premature infant in an incubator. It might have individual rights; defining the point at which this became true would be a complex question of legal philosophy. Fortunately it's not one we need to settle now.