Should We Retire Derek Parfit?

For nearly a generation, Derek Parfit's arguments in his 1984 book Reasons and Persons have shaped debates about our moral responsibilities to future people. Struggling to accommodate Parfit's insights, philosophers and bioethicists have minimized or accentuated obligations to the future in ways that defy ordinary moral intuitions. In this issue, Robert Sparrow develops the troubling implications of the views of two leading theorists whose work favoring human genetic enhancement is influenced by Parfit. Sparrow believes they return us to the horrors of early twentieth-century eugenics. But the real problem may be a purely theoretical one: the unfortunate influence of Parfit.

This is no place to review all of Parfit's complex and brilliantly developed arguments. I can, however, present his core insights. One is that in certain decisions that affect which person is born—what he calls "person-affecting decisions"— there may be no one harmed by the decision, even if its outcome is terrible. For example, imagine a woman who has contracted rubella and wants to become pregnant. Her doctor warns her to delay conception because the child runs the risk of birth defects, but the woman ignores the advice, and her child is born blind, deaf, and with severe heart disorders. Many of us think that the mother has acted irresponsibly. But Parfit points out that the impaired child cannot say that he has been harmed. Normally, one is harmed if one is made worse off than one would have been. But if the mother had taken the doctor's advice, a different child would have been born at a later date. One can perhaps argue that the impaired child would be better off if it had not been born rather than being born with severe impairments, but most people prefer being alive to being dead, no matter how bad their condition. Faced with these counterintuitive conclusions, Parfit moved to an "impersonal" account of moral judgment. On this account, the moral goal is to increase welfare in the world and reduce suffering. The mother acts irresponsibly if she refuses to defer conception, as her decision decreases the net sum of well-being in the world.

Parfit's presence haunts Sparrow's discussion in two crucial ways. First, Parfit's argument for an impersonal account of obligations to the future helps support the consequentialist or utilitarian approaches adopted by the two theorists Sparrow examines, Julian Savulescu and John Harris. Sparrow correctly identifies a number of problems in their views. But the underlying problem is not enhancement technology. It lies in what Sparrow describes as the "notoriously demanding nature of consequentialism."

Parfit appears a second time when Sparrow critiques Harris's efforts to escape the totalitarian implications of consequentialism. Harris argues that his commitment to enhancement will not infringe parental reproductive liberty because there will be few occasions when parents' choices, no matter how seemingly unfortunate, will actually wrong a child. Harris gives a very Parfit-like argument that, unless the child's state is worse than death, the parents will not have acted wrongly. But Harris's efforts to preserve parental liberty do not quite square with his consequentialism.

Perhaps we can restore sanity by dismissing Parfit and saying that parents both harm and wrong children by imposing even modest damage on them through irresponsible reproductive decision-making. Other things being equal, a woman who knowingly refuses to delay conception after exposure to a teratogen acts irresponsibly. At the same time, we may not have to appeal to the absence of catastrophic outcomes (lives worse than death) to also defend a strong degree of parental reproductive autonomy.

How can we do this? The answer in my view lies in a sound basic theoretical approach. In the tradition of Kant, Rawls, Gert, myself, and others, the right thing to do is the thing that omnipartial, rational persons would accept as a public rule of conduct. This ideal community of moral legislators would be very cautious about reprogenetic decisions that inflict even modest harms. From this theoretical perspective, wrongful behavior does not have to involve harm to a living person (as shown by moral rules prohibiting violations of someone...