The New York Times has
an excellent piece by Steven Pinker on the human instinct for moral reasoning:
At the same time, many behaviors have been amoralized, switched from moral failings to lifestyle choices. They include divorce, illegitimacy, being a working mother, marijuana use and homosexuality. Many afflictions have been reassigned from payback for bad choices to unlucky misfortunes. There used to be people called “bums” and “tramps”; today they are “homeless.” Drug addiction is a “disease”; syphilis was rebranded from the price of wanton behavior to a “sexually transmitted disease” and more recently a “sexually transmitted infection.”
This wave of amoralization has led the cultural right to lament that morality itself is under assault, as we see in the group that anointed itself the Moral Majority. In fact there seems to be a Law of Conservation of Moralization, so that as old behaviors are taken out of the moralized column, new ones are added to it. Dozens of things that past generations treated as practical matters are now ethical battlegrounds, including disposable diapers, I.Q. tests, poultry farms, Barbie dolls and research on breast cancer. Food alone has become a minefield, with critics sermonizing about the size of sodas, the chemistry of fat, the freedom of chickens, the price of coffee beans, the species of fish and now the distance the food has traveled from farm to plate.
While what is considered a moral issue differs between cultures and societies (and, to an extent, periods of time), there appear to be five categories for moral judgment hardwired into the human psychology: harm, fairness, community (or group loyalty), authority and purity.
The five spheres are good candidates for a periodic table of the moral sense not only because they are ubiquitous but also because they appear to have deep evolutionary roots. The impulse to avoid harm, which gives trolley ponderers the willies when they consider throwing a man off a bridge, can also be found in rhesus monkeys, who go hungry rather than pull a chain that delivers food to them and a shock to another monkey. Respect for authority is clearly related to the pecking orders of dominance and appeasement that are widespread in the animal kingdom. The purity-defilement contrast taps the emotion of disgust that is triggered by potential disease vectors like bodily effluvia, decaying flesh and unconventional forms of meat, and by risky sexual practices like incest.
The ranking and placement of moral spheres also divides the cultures of liberals and conservatives in the United States. Many bones of contention, like homosexuality, atheism and one-parent families from the right, or racial imbalances, sweatshops and executive pay from the left, reflect different weightings of the spheres. In a large Web survey, Haidt found that liberals put a lopsided moral weight on harm and fairness while playing down group loyalty, authority and purity. Conservatives instead place a moderately high weight on all five. It’s not surprising that each side thinks it is driven by lofty ethical values and that the other side is base and unprincipled.
And, further down:
Though wise people have long reflected on how we can be blinded by our own sanctimony, our public discourse still fails to discount it appropriately. In the worst cases, the thoughtlessness of our brute intuitions can be celebrated as a virtue. In his influential essay “The Wisdom of Repugnance,” Leon Kass, former chair of the President’s Council on Bioethics, argued that we should disregard reason when it comes to cloning and other biomedical technologies and go with our gut: “We are repelled by the prospect of cloning human beings . . . because we intuit and feel, immediately and without argument, the violation of things that we rightfully hold dear. . . . In this age in which everything is held to be permissible so long as it is freely done . . . repugnance may be the only voice left that speaks up to defend the central core of our humanity. Shallow are the souls that have forgotten how to shudder.”
There are, of course, good reasons to regulate human cloning, but the shudder test is not one of them. People have shuddered at all kinds of morally irrelevant violations of purity in their culture: touching an untouchable, drinking from the same water fountain as a Negro, allowing Jewish blood to mix with Aryan blood, tolerating sodomy between consenting men. And if our ancestors’ repugnance had carried the day, we never would have had autopsies, vaccinations, blood transfusions, artificial insemination, organ transplants and in vitro fertilization, all of which were denounced as immoral when they were new.