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Tamler Sommers Ph.D.
Tamler Sommers Ph.D.

What’s the Matter With a Little Brother/Sister Action?

What our reaction to incest can tell us about morality.

Fellow "Experiments in Philosophy" blogger Jesse Prinz posted about UVA psychologist Jon Haidt's work on political differences. I want to continue exploring the philosophical implications of Haidt's work by asking whether it's all right for Julie and her brother Mark to have sex.

Here's a scenario drawn from a study Haidt conducted:

"Julie and Mark are brother and sister. They are traveling together in France on summer vacation from college. One night, they are staying alone in a cabin near the beach. They decide that it would be interesting and fun if they tried making love. At the very least, it would be a new experience for each of them. Julie was already taking birth control pills, but Mark uses a condom, too, just to be safe. They both enjoy making love, but they decide never to do it again. They keep that night as a special secret, which makes them feel even closer to each other. What do you think about that? Was it okay for them to make love?"

If you're like most people, your response is "absolutely not," but you'll find it more difficult than you think to come up with a justification. "Genetic defects from inbreeding." Yes, but they were using two forms of birth control. (And in the vanishingly small chance of pregnancy, Julie can get an abortion.) "It will mess them up emotionally." On the contrary, they enjoyed the act and it brought them closer together. "It's illegal." Not in France. "It's disgusting." For you, maybe, but not for them (obviously). Do you really want to say that private acts are morally wrong just because a lot of people find those acts disgusting? And so on.

The scenario, of course, is designed to ward off the most common moral objections to incest, and in doing so demonstrate that much of moral reasoning is a post-hoc affair—a way of justifying judgments that you've already reached though an emotional gut response to a situation. Although we like to think of ourselves as arriving at our moral judgments after painstaking rational deliberation (or at least some kind of deliberation) Haidt's model—the "social intuititionist model"—sees the process as just the reverse. We judge and then we reason. Reason is the press secretary of the emotions, as Haidt is fond of saying—the ex post facto spin doctor of beliefs we've arrived at through a largely intuitive process.

As Haidt recognizes, his theory can be placed within a grand tradition of moral psychology and philosophy—a return to an emphasis on the emotions which began in full force with the work of Scottish philosophers Adam Smith and David Hume. Although the more rationalist theories of Piaget and Kohlberg were dominant for much of the twentieth century, Haidt-style views have gained more and more adherents over the last 10 years. Which leads to the question: are there any philosophical/ethical implications of this model, should it be the right one? Plenty, in my view, and I'll conclude this post by mentioning just a few of them.

First, although Haidt may disagree (see my interview with him for a discussion about this issue), I believe Haidt's model supports a subjectivist view about the nature of moral beliefs. My thinking is as follows: We arrive at our judgments through our emotionally charged intuitions—intuitions that do not track any kind of objective moral truth, but instead are artifacts of our biological and cultural histories. Haidt's model reveals that there is quite a bit of self-deception bound up in moral beliefs and practice. The strength of these intuitions leads us to believe that the truth of our moral judgments is "self-evident"—think: the Declaration of Independence—in other words, that they correspond to an objective moral reality of some kind. That is why we try so hard to justify them after the fact. But we have little to no reason to believe that this moral reality exists.

(I should add that contrary to the views of newspaper columnists across the country, claiming that a view might lead to moral relativism or subjectivism is not equivalent to saying that the view is false. This is not a reductio ad absurdum. If Haidt's model is vindicated scientifically, and it does indeed entail that moral relativism or subjectivism is true, then we have to accept it. Rejecting a theory just because you feel uncomfortable about its implications is a far more skeptical or nihilistic stance than anything I've discussed in this post.)

Second, and less abstractly, I think it would make sense to subject our own values to far more critical scrutiny than we're accustomed to doing. If Haidt is right, our values may not be on the secure footing that we believe them to be. We could very well find that upon reflection, many of our values do not reflect our considered beliefs about what makes for a good life.

It's important to note that Haidt does not claim that it's impossible for reason to change our moral values or the values of others. He just believes that this kind of process happens far less frequently than we believe—and furthermore, that when values are affected by reason, it is because reason triggers a new emotional response which, in turn, starts a new chain of justification.

Finally, I think we might become a little more tolerant of the moral views of others (within limits, of course—sometimes too much tolerance is tantamount to suicide). Everyone is morally motivated, as Haidt says: liberals should stop thinking of conservatives as motivated only by greed and racism. And conservatives should stop thinking of liberals as—as Jesse Prinz puts it in his post—"either tree-hugging fools or calculating agents of moral degeneracy."

More importantly, if Haidt is correct, we must recognize even the people we consider to be the epitome of pure evil—the Islamic fundamentalists who engineered 9/11, for example—are motivated by moral goals, however distorted we find them to be. As Haidt told me in our interview:

"One of the most psychologically stupid things anyone ever said is that the 9/11 terrorists did this because they hate our freedom. That's just idiotic. Nobody says: 'They're free over there. I hate that. I want to kill them.' They did this because they hate us; they're angry at us for many reasons, and terrorism and violence are 'moral' actions—by which I don't mean morally right, I mean morally motivated."

It seems plausible that in order to shape our policies properly, we need to have an accurate understanding of the moral motivations of the people with whom we're at war.


Further reading:

Haidt, J . (2001). The emotional dog and its rational tail: A social intuitionist approach to moral judgment. Psychological Review. 108, 814-834

August 2005 interview with Jon Haidt in The Believer.

About the Author
Tamler Sommers Ph.D.

Tamler Sommers is a professor of philosophy at the University of Houston.

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