How Can Evolution and Neuroscience Help Us Understand Moral Capacities?

Trying to understand morality has been a central human preoccupation for as far back as human history extends, and for very good reasons. The core phenomenon is readily observable: we humans judge each other’s behaviour as right or wrong, and each other’s selves as moral or immoral. If others view you as moral, you will thrive in the bosom of a human group. If, however, others view you as immoral, you are in deep trouble; you may even die young, either at the hands of others, or alone in the bush. These are very good reasons indeed for close attention to morality. There are, however, two problems. The first is how to distinguish right from wrong, the second is inhibiting temptations to do what is wrong (that temptations to do right are not a problem is most interesting). The first problem poses few concerns for most people – they are confident that they know what is right, based on their intuitive emotional responses. However, different people have different emotional responses, and intuition makes a poor argument. Finding a general principle that explains the individual instances would be incredibly valuable. So, for several thousands of years, philosophers have tried to find general moral principles. They have also argued about where they come from, why they have normative force, and how they are best applied to individual instances (Darwall, Gibbard, & Railton, 1997). Thousands of books chronicle the human quest for moral knowledge. Now, in a mere eye blink of history, the scene has changed. Completely new kinds of knowledge are being brought to bear. Neuroscience is investigating the brain mechanisms involved in moral decisions, moral actions, and responding to moral and immoral actions by self and others. Evolutionary biology is investigating why those brain mechanisms exist, how they give a selective advantage, and why there is genetic variation that influences moral tendencies. This is an exciting time for those of us curious about morality.