I found this quite unconvincing, so unconvincing that I looked for more on Jonathan Haidt, and found what I turned up unconvincing too. And not just unconvincing, but also unfortunate.

“Psychologist Jonathan Haidt wants to help liberal types like me understand why some people condemn homosexual relationships as immoral.” Imagine someone saying ‘Gay marriage will destroy society, because homosexuality is an abomination to God and will undermine marriage.’ Liberals think that’s a bad reason.

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.

I don’t think so. I think it’s based on a moral compass that is wrong. It’s not a failure to perceive, it’s a disagreement. In particular we disagree over god, and over what is or is not an abomination to any putative god, and over whether gay marriage will undermine marriage. There’s no sensory lack there; there’s disagreement, which is a different thing.

In Western societies, secular and liberal-minded people base their moral beliefs on fairness and the avoidance of harm…Most people set their moral compasses based on their sense of disgust. This is an additional moral dimension, which [Haidt] calls purity/sanctity.

You bet. Lots of people fret a good deal about purity and sanctity. We realize that – and we think it’s a mistake, usually a terrible mistake.

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.

But that doesn’t make disagreement (or ‘disdain,’ if you insist on prejudicing the argument) misplaced. We understand that the moral compass of the religious right factors in disgust, and that’s exactly what we object to; they shouldn’t be disgusted, the disgust is irrational; and they certainly shouldn’t try to enforce their own disgust as a matter of law. If I want to eat slugs for lunch, what is that to them?!

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.”

Well there’s your problem right there: don’t ever be inspired by Leon Kass. He talks terrible nonsense about instinctive revulsion that can’t be argued. Well yeah, like for people of other races, or women, or people with disabilities, or people of the wrong religion.

University of Pennsylvania bioethicist Arthur Caplan disagrees with Kass’ use of intuition…”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.”

Just so.

Haidt goes into more detail in an interview.

Haidt has devoted his career to the study of moral judgment and decision-making; his results are revealing and perhaps a bit unflattering. We tend to think of ourselves as arriving at our moral judgments after painstaking rational deliberation, or at least some kind of deliberation anyhow. According to Haidt’s model—which he calls “the social intuitionist model”—the process is just the reverse. We judge and then we reason. What, then, is the point of reasoning if the judgment has already been made? To convince other people (and also ourselves) that we’re right.

Well, we already knew that of course; we’ve read our Hume and our Damasio; we’ve taken the Taboo test (which was inspired by Haidt’s work); we know we react first and think afterwards. But I don’t agree with the last sentence, at least not unless it’s worded differently. What’s the point of thinking about our first emotional judgment? To try to figure out whether it’s right or not! To second-guess it; to think; to consider; to ask if we’re just shooting from the hip.

It’s an interesting interview – full of places where one thinks ‘No, not exactly,’ but interesting. But some of what he says…

What I want to say is that there are at least four foundations of our moral sense, but there are many coherent moral systems that can be built on these four foundations. But not just anything can be built on these four foundations. So I believe that an evolutionary approach specifying the foundation of our moral sense can allow us to appreciate Hindu and Muslim cultures where women are veiled and seem to us to lead restricted lives.

But I don’t want to appreciate Hindu and Muslim cultures where women seem to lead restricted lives. I think if they seem to lead restricted lives, they do lead restricted lives, and I know enough about the subject to know that when their lives expand, they tend to be overjoyed; therefore I have no desire to appreciate cultures where they don’t even have that option, where they can’t even sample expansion to see if they like it.

Liberals use intuitions about suffering (aversion to) and intuitions about reciprocity, fairness, and equality. But there are two other foundations—there are intuitions about hierarchy, respect, duty… that’s one cluster. And intuitions about purity and pollution, which generate further intuitions about chastity and modesty. Most human cultures use all four of these bases to ground their moral worldviews. We in the West, in modern times especially, have to some extent discarded the last two. We have built our morality entirely on issues about harm (the first pillar), and rights, and justice (the second). Our morality is coherent. We can critique people who do things that violate it within our group. We can’t critique cultures that use all four moralities.

Oh yes we can.