How can someone who condemns animal farming, hunting, and experimentation favor a right to abortion? Abortion, after all, is the deliberate taking of a human life, or at least of a potential human life. Yet many in the animal-rights movement support legal abortion. Do animal-rights activists care more about the well-being of nonhuman animals than about the survival of tiny humans?
Conversely, how can people who would ban the destruction of even a one-celled human zygote — an entity as simple as an amoeba and possessing no more consciousness than a fingernail or a strand of hair — eat and use the flesh, skin, and secretions of feeling creatures like cows, pigs, and chickens whose lives were filled with unspeakable suffering, ended only by horrific deaths? Do pro-life activists care more about a human cell than about the suffering of fully sentient animals whose evolutionary history, brain chemistry, and emotional repertoire closely resemble our own?
It is possible to favor both animal rights and the rights of embryos and fetuses, and some people are active in both movements. For the most part, however, the animal-rights movement and the pro-life campaign do not overlap, except perhaps in their willingness to expropriate each other’s catch phrases. A pro-life bumper sticker depicts a cartoon seal holding a placard that reads "save the baby humans." An animal-rights sign says "a hamburger stops a beating heart."
Yet more than rhetoric connects the pro-life and animal-rights movements. Each kind of activism challenges conventional views about the moral relevance of membership in the human species. People in the pro-life movement regard humanity as a sufficient condition for moral rights; animal-rights advocates reject the notion that humanity is a necessary condition for moral rights.
Seen in this way, the mystery dissolves. There is so little overlap between the movements because each asserts what the other denies. Opposition to ending a pregnancy, even in its earliest stages, rests on the view that the humanity of a zygote, embryo, or fetus makes all the difference. Rejection of the slaughter and use of animals for food, fiber, and entertainment rests on the view that an animal’s nonhuman status makes no difference.
Nonetheless, animal-rights supporters still find themselves on the defensive if they support abortion rights, because the best argument for animal rights implies that at least some abortions are immoral. To see why, we must examine the basis for rights.
In our view, sentience grounds moral rights. Sentience is the ability to have subjective experiences. A being who can feel pleasure or pain is, in virtue of that ability, sentient. Indeed, the ability to have subjective experiences is precisely what makes a being a being, "someone" rather than "something."
Most reasonably complex living animals, including humans, are provably sentient. So are fetuses at some point in their development. Inanimate objects and (so far as we know) plants are not sentient. Sentient creatures respond to external stimuli, but such responses alone do not always indicate sentience. A thermostat that directs a furnace to fire up when the temperature dips below the set point responds to an external stimulus. So does a sunflower displaying heliotropism. But we have no good reason to think that a thermostat or a sunflower feels anything. We can vaguely imagine what it might feel like to be a hummingbird, a shark, or a squirrel, but we cannot envision what it would feel like to be a thermostat or a sunflower. It would not feel like anything.
People who oppose abortion generally reject sentience as the basis for moral consideration. They think that it is wrong to destroy a human zygote, embryo, or fetus even at the very beginning of pregnancy simply because it is human. Perhaps they have religious reasons for this view, or perhaps they think that abortion is a waste of the precious gift of life. We agree with the late legal philosopher Ronald Dworkin’s contention that "a fetus cannot have interests of its own before it has a mental life," but we question his conclusion that abortion opponents therefore cannot really mean that abortion harms a presentient fetus. Certainly many pro-life activists say exactly that, and we have no reason to doubt their sincerity.
In recent years, however, the pro-life movement has also implied that sentience matters. By supporting laws that ban abortions of "pain capable" fetuses, they tacitly acknowledge that there is something especially problematic about ending the life of a being that can experience that life. To be sure, the emphasis on fetal pain may be best understood as an effort to appeal to those elements of the general public who do not hold strong pro-life views, but that tactical choice is itself telling. Like laws that forbid so-called "partial-birth abortion" and other late-term abortions, laws forbidding the abortion of "pain capable" fetuses trade on the widely shared moral intuition that abortion is wrong only (or especially) insofar as it harms someone who can suffer.
The push for abortion prohibitions based on the fetus’s capacity for pain thus reflects at least tactical acceptance of the animal-rights perspective by the pro-life movement. What about the flip side? Should animal-rights activists meet the pro-life activists halfway and support an abortion prohibition for sentient fetuses?
Not necessarily. Some abortions of sentient fetuses are morally justified, if nonetheless tragic. For example, some women have late-term abortions to avoid serious health risks. True, from an animal-rights perspective, the abortion of a sentient fetus will sometimes be immoral, as when a woman simply waits until late in pregnancy to decide that she does not want to bear a child. But even then, it does not follow that an immoral abortion should necessarily be illegal as well.
We are both lawyers by training, and perhaps for that reason we are acutely aware of the law’s shortcomings and limitations. In some circumstances, attempts to command compliance with an unpopular mandate may backfire, causing collateral damage. That is the accepted wisdom about what went wrong with the prohibition of alcohol, and it is at least an arguable account of the regime of abortion regulation that preceded the U.S. Supreme Court’s 1973 decision in Roe v. Wade. Prohibition of alcohol led to the violence associated with bootlegging, while prohibition of abortions led to the violence associated with back-alley procedures.
In other circumstances, even where there is no practical obstacle to enforcing a legal rule, it may be appropriate to commit the matter to individual conscience. Thus, constitutional democracies permit freedom of speech even though many instances of its exercise will be irresponsible and even harmful. Likewise, we think it appropriate for the law to permit women the freedom to choose abortion, even though some particular exercises of that freedom will be immoral.
There is an asymmetry here, of course. We tolerate obnoxious speech because it is, at the end of the day, just words. By contrast, abortion of a sentient fetus ends a life. Therefore, libertarian principles alone may not be sufficient to warrant a legal right to late-term abortion.
Accordingly, most efforts at justifying abortion rights also invoke notions of bodily integrity and sex equality. Viewing abortion in juxtaposition with animal rights adds a striking analogy. Women who are denied the right to have abortions are placed in a kind of invasive reproductive servitude that resembles the reproductive servitude in which dairy cows and laying hens are held. In each case, females’ bodies are invaded and their reproductive capacities used for the benefit of others. Abortion prohibitions appropriate the wombs of women for the benefit of fetuses; dairy and egg production appropriates the bodies of cows and hens for the benefit of the people who will eventually eat the dairy and egg products.
We doubt that either pro-choice feminists or pro-life activists will particularly like the comparison of human women to cows and hens. Nonetheless, we offer it with the best of intentions. Because we reject speciesism, we do not think it an insult to humans to observe the ways in which exploitation of disadvantaged members of our species resembles the exploitation of other animals.
Thinking about abortion rights and animal rights as closely related also reveals common strategic questions. Do gory images of dead fetuses or animals win hearts and minds to the respective causes, or merely alienate the public? Why is violence against abortion providers and animal exploiters objectionable, given the harm that such violence seeks to avert? Should activists promote regulatory measures that do not fundamentally challenge the status quo? Pro-lifers do so, for instance, when they support late-term-abortion restrictions that tacitly concede that fetal sentience, rather than mere membership in the human species, grounds moral rights. Animal activists make similar compromises when seeking welfare measures like larger cages that tacitly accept that using animals’ flesh and secretions may not be objectionable in itself.
Neither the basic moral question nor the myriad strategic questions are likely to produce consensus any time soon. Nonetheless, by seeing the commonalities between the debate over abortion and animal rights, all parties can gain a better appreciation of their opponents’ views — and of their own.
Sherry F. Colb and Michael C. Dorf are professors of law at Cornell University. They are the authors of Beating Hearts: Abortion and Animal Rights (Columbia University Press, 2016).