Is Morality Natural?

Our emotions do, however, have a great impact on our actions. How we judge what is right or wrong may well be different from what we chose to do in a situation. For example, we may all agree that it is morally permissible to kill one person in order to save the lives of many. When it comes to actually taking someone's life, however, most of us would turn limp.

Another example of the role that emotions have on our actions comes from recent studies of psychopaths. Take the villains portrayed by Heath Ledger and Javier Bardem, respectively, in "The Dark Knight" and "No Country for Old Men." Do such psychopathic killers know right from wrong? New, preliminary studies suggest that clinically diagnosed psychopaths do recognize right from wrong, as evidenced by their responses to moral dilemmas. What is different is their behavior. While all of us can become angry and have violent thoughts, our emotions typically restrain our violent tendencies. In contrast, psychopaths are free of such emotional restraints. They act violently even though they know it is wrong because they are without remorse, guilt or shame.

These studies suggest that nature handed us a moral grammar that fuels our intuitive judgments of right and wrong. Emotions play their strongest role in influencing our actions—reinforcing acts of virtue and punishing acts of vice. We generally do not commit wrong acts because we recognize that they are wrong and because we do not want to pay the emotional price of doing something we perceive as wrong.

So, would you have killed the large woman stuck in the cave or allowed her to die with the others? If you are like other subjects taking the moral sense test, you would say that it is permissible to take her life because you don't make her worse off. But could you really do it? Fortunately, there was a simpler solution: she was popped out with paraffin after 10 hours.

Hauser is a professor of psychology and human evolutionary biology at Harvard, and author of “Moral Minds” (Ecco/HarperPerennial).

© 2008