Psychologist; Historian of science; Publisher, Skeptic Magazine; Author, The Moral Arc
The Nature of Human Nature

When I was a graduate student in experimental psychology I cut my teeth in a Skinnerian behavioral laboratory. As a behaviorist I believed that human nature was largely a blank slate on which we could impose positive and negative reinforcements (and punishments if necessary) to shape people and society into almost anything we want. As a young college professor I taught psychology from this perspective and even created a new course on the history and psychology of war, in which I argued that people are by nature peaceful and nonviolent, and that wars were thus a byproduct of corrupt governments and misguided societies.

The data from evolutionary psychology has now convinced me that we evolved a dual set of moral sentiments: within groups we tend to be pro-social and cooperative, but between groups we are tribal and xenophobic. Archaeological evidence indicates that Paleolithic humans were anything but noble savages, and that civilization has gradually but ineluctably reduced the amount of within-group aggression and between group violence. And behavior genetics has erased the tabula rasa and replaced it with a highly constrained biological template upon which the environment can act.

I have thus changed my mind about this theory of human nature in its extreme form. Human nature is more evolutionarily determined, more cognitively irrational, and more morally complex than I thought.