Harvard psycholinguist Steven Pinker examines the evolutionary roots of morality in a fascinating article in the Sunday New York Times. Among other things, Pinker outlines University of Virginia psychologist Jonathan Haidt's work which identifies five consistent themes of moral thinking. As Pinker explains:
…Haidt counts five — harm, fairness, community (or group loyalty), authority and purity — and suggests that they are the primary colors of our moral sense. Not only do they keep reappearing in cross-cultural surveys, but each one tugs on the moral intuitions of people in our own culture…
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… 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….
According to Pinker, Haidt has also identified differential evaluations among the five moral themes between liberals and conservatives in America.
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.
Haidt thinks that this means that conservatives are better at understanding liberals (since they share the values of no harm and fairness) than liberals are at understanding conservatives (whose values also include group loyalty, deference to authority, and concerns about purity). Does science demystify morality and thus undercut it?
The institutions of modernity often question and experiment with the way activities are assigned to moral spheres. Market economies tend to put everything up for sale. Science amoralizes the world by seeking to understand phenomena rather than pass judgment on them. Secular philosophy is in the business of scrutinizing all beliefs, including those entrenched by authority and tradition. It's not surprising that these institutions are often seen to be morally corrosive….
Far from debunking morality … the science of the moral sense can advance it, by allowing us to see through the illusions that evolution and culture have saddled us with and to focus on goals we can share and defend. As Anton Chekhov wrote, "Man will become better when you show him what he is like."