Two renowned philosophers, Jeff McMahan and Peter Singer, recently took to the website of the New York Times to defend a female academic convicted on two counts of aggravated sexual assault on a twenty-nine-year-old man with severe cerebral palsy. Much of their article focuses on whether the man in question is sufficiently intellectually disabled to be incapable of consenting to sex with professor of ethics Anna Stubblefield. Stubblefield claims that the sex was consensual and part of a loving relationship. The authors, as well as discussing the available evidence, also question the justice of the court proceedings which, they claim, barred evidence favorable to the defense.

My purpose in this article is not to examine the evidential case set forth by McMahan and Singer. Instead, I draw your attention to this argument they make:

If we assume that [the alleged victim, D.J.] is profoundly cognitively impaired, we should concede that he cannot understand the normal significance of sexual relations between persons or the meaning and significance of sexual violation. . . . In that case, he is incapable of giving or withholding informed consent to sexual relations; indeed he may lack the concept of consent altogether.

This does not exclude the possibility that he was wronged by Stubblefield, but it makes it less clear what the nature of the wrong might be. It seems reasonable to assume that the experience was pleasurable to him . . . it seems that if Stubblefield wronged or harmed him, it must have been in a way that he is incapable of understanding and that affected his experience only pleasurably.

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In order to see how people come to make such statements, it is worth taking a look at some of the philosophical assumptions guiding both McMahan and Singer.

Singer’s Hedonistic Utilitarianism

Peter Singer is, by his own account, a hedonistic utilitarian (he has jettisoned his former embrace of a preference-based account of human well-being). He follows his hero Jeremy Bentham, telling readers that his philosophy “eliminates the direct significance of the distinction between persons—defined as self-conscious beings who are aware of their existence over time—and sentient beings who are not” before adding that he essentially rejects “Mill’s distinction between higher and lower pleasures.”

Singer’s philosophy of maximizing pleasure and minimizing suffering is so beset with serious problems it is something of a wonder that he still sticks to it. His account of value reduces all notions of “good,” “bad,” “should,” and “should not” to mere measurements of pleasure or pain. But if that’s the case, then how does it make sense to talk of a duty to maximize pleasure that isn’t itself pleasurable? Such an ethic leaves no room for consideration of human flourishing consisting of more than “felt satisfaction” of some kind, to say nothing of intentions and side effects, doing and allowing, character and virtue, and so on. Nor does it have an answer to the fact that pleasure, unlike fundamental goods such as knowledge, life, and justice, can be taken in evil acts (including raping someone incapable of consent) and thus can become evil in itself.

Such a system has no place for negative moral absolutes of any kind, nor for the relevance of a human nature that is valuable in itself and grounds moral norms and basic human rights. The whole system seems to rely on the idea of an “objectively good state of affairs,” but it is difficult to make sense of that without reference to some agent, an agent who “should” desire such a state—because it is a state that is virtuous to desire. “Virtue” is thus no less basic than “good,” and particular goods will be virtuous for a particular agent to desire in a special way in some particular role. Singer ignores the role of virtue in understanding what an objectively good state of affairs might mean.

In addition, Singer infamously values the lives of many animals above human infants and the mentally disabled. He endorses infanticide as well as non-voluntary and even involuntary euthanasia. Humanity and human nature and the goods to which it is inherently oriented possess no special value in the eyes of the pleasure-calculating impartial observer who surveys all. To assert that human nature, or any rational nature, has special value is to be guilty of “speciesism.” Despite this, Singer is a professor at Princeton University’s Center for Human Values. This position once prompted Bernard Williams to wonder how he feels about such a human-centric title, musing “I should have thought it would have sounded to him rather like a Center for Aryan Values.”

Sexual Ethics

Having thus downgraded the human species, its more vulnerable members and pretty much everything about them of value, Singer tells us, in relation to sex,

ethics is not a set of prohibitions particularly concerned with sex . . . sex raises no unique moral issues at all. Decisions about sex may involve considerations of honesty, concern for others, prudence and so on, but there is nothing special about sex in this respect, for the same could be said about decisions about driving a car.

Showing the same “color-blindness” to questions of sexual ethics, Singer many years later endorsed bestiality as potentially a good moral option, which should cease to be “an offence to our status and dignity as human beings.” It is not clear what Singer now means by status and dignity as they relate to human beings, but I think his position regarding the Stubblefield case gives us some idea.

Jeff McMahan, a highly sophisticated philosopher, rejects Singer’s crude utilitarianism and his account of human “replaceability,” and endorses the importance of the principle of double effect as well as much of traditional just war theory. As far as I know, he has not written on sexual ethics as such. He does, however, endorse positions similar to Singer’s on infanticide and on euthanasia.

When it comes to sexual matters, it is important to remember that non-consensual sex is not merely consensual sex minus consent. As Susan Brison has pointed out, sex should not be seen as a simple and invariant factor in both rape and consensual sex, any more than we think of theft as coerced gift-giving. If that is correct, then it certainly does not follow that someone who is raped or assaulted (“non-consensual sex”) is any less wronged for the fact that they are unable to appreciate the value and meaning of consensual sex.

Yet, for McMahan and Singer, on the assumption that D.J. was incapable of consent to a sexual act in the sense of being able to understand its normal significance, “it seems that if Stubblefield wronged or harmed him, it must have been in a way that he is incapable of understanding and that affected his experience only pleasurably.”

McMahan and Singer seem unable or unwilling to conceive that pleasure can be taken in something either morally wrong or otherwise inappropriate. If someone—a small child, for example—is incapable of understanding the significance of sex but is pleasurably affected by sexual acts performed upon him or her, then these two philosophers would presumably have difficulty in seeing any way in which the child would be wronged or harmed. On such a view, pedophilia might be permitted. Indeed, for McMahan and Singer, babies and perhaps toddlers (not to mention the seriously intellectually disabled) do not even count as “persons” and can, in certain circumstances, be killed. Why not also say that they can be sexually abused, especially as they might gain some pleasure from such treatment? What, it might be asked, would be the “nature of the wrong” in such cases, especially where there was little resistance?

Of course, McMahan and Singer may point out that they don’t deny that D.J. might have been harmed even if he was incapable of consent. But to understand such harm they would need to understand something about the value and meaning of sex. One is unlikely to be sensitive to that value if one thinks that very young human beings or the intellectually disabled can be classified as non-persons. Human beings, as members of the rational human species who flourish in ways no other animal can flourish, possess a special and intrinsic value. One cannot fully understand the dignity of human beings without attending to the importance of our sexual nature and capacities, which have a significance in human life quite unlike the significance of sex for animals. And the more you minimize the value of humanity itself, the less you will be capable of understanding our fundamental rights, the meaning of our bodies, and the gift of sexuality.

Focus on the “pleasurable” obscures the fact that harm comes in many forms, especially in the complex, rich, and problematic area of sexual behavior. Perhaps it is time that the dignity of the vulnerable received more attention from philosophers generally. As a start, it might be good if Singer and McMahan developed a notion of harm rich enough to include the harm their own article has done to the intellectually disabled.