If you're a liberal, you may view both neighbors as equally out of touch with reality (though the woman with the theta-wave theory is more original). That's the way most academics would traditionally see it, too.
But Haidt, who works at the University of Virginia and specializes in issues of morality, says the conservative viewpoint isn't just theta waves - it's based on a moral compass that points in dimensions liberals simply don't perceive.
"There's been this enormous change in how scientists are thinking about morality," he says. He outlined the new view recently in the journal Science.
In Western societies, secular and liberal-minded people base their moral beliefs on fairness and the avoidance of harm. That explains why, in previous columns, I wrote that I saw nothing immoral about premarital sex, homosexuality or sex toys - except, perhaps, for nonrecyclable batteries.
Dozens of horrified readers quickly blasted me as disgusting.
Which Haidt says is exactly the point. Most people set their moral compasses based on their sense of disgust. This is an additional moral dimension, which he calls purity/sanctity.
But why do so many people think homosexuality is disgusting? I never had any problem with it.
University of Pennsylvania psychologist and disgust expert Paul Rozin says it's particularly a guy thing - most heterosexual men are disgusted by the thought of touching other men. Rozin recalls experiments in which researchers asked subjects how disgusted they'd be if a Q-tip that had been in the mouth of either a man or a woman was subsequently touched to their own various orifices.
Women didn't care much whether the swab had touched the mouth of a man or a woman. But it mattered to men, who - surprise! - were not at all disgusted by the Q-tip that touched a woman but totally grossed out if they thought it had touched another guy's tongue.
Isn't it kind of babyish to declare gays immoral because you think their sex lives are icky?
Rozin suggests that liberals tend to go after smokers partly for the same reason. It's far from a perfect analogy, and I'm not really bothered by smokers. To me, slaughterhouses are disgusting and cast doubt on the morality of buying supermarket steak (although not enough to stop me from eating a hamburger at a barbecue).
And Haidt and Rozin both say that widespread disdain for fundamentalists is misplaced. The moral compass of the religious right factors in that additional dimension of sanctity/purity, which is driven by disgust as well as religious teachings.
Haidt says he was inspired by the University of Chicago's Leon Kass, who headed President Bush's Council on Bioethics from 2002 to 2005. In an earlier essay, called "The Wisdom of Repugnance," Kass wrote that feelings of disgust come from "an emotional expression of a deep wisdom. . . . Shallow are the souls that have forgotten how to shudder."
Kass' essay focused not on gay marriage, but on human cloning, which, he wrote, makes us uneasy for a reason.
University of Pennsylvania bioethicist Arthur Caplan disagrees with Kass' use of intuition. When cloning began making news in the 1990s, Caplan opposed human cloning because it might lead to birth defects or other harm and held no obvious benefit - not because it was revolting.
"People used to think it was revolting when two people of different races got married," Caplan says. Letting your sense of disgust guide your views on gay marriage, he adds, "is just bigotry and bias dressed up with the clothes of wisdom."
Carnal Knowledge | Health & Science
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