of human nature, including emotional sensitivity, warmth, and flexibility. When we transform others into animals, we have stripped them of uniquely human qualities such as rationality, self-control, moral sensibility, and civility. Of those who are like animals, some will seem like kin to the domesticated form and thus controllable as property; others will seem like wild animals and thus dangerous, dirty and deserving of elimination. However we engage this process, we have bleached individuals of their humanity. This process, one that occurs in both everyday life and in cases of conflict, has allowed us to treat the mentally and physically disabled like animals, to consider women as sexual property, justify slavery and slave wages, deny certain races the opportunity to vote and receive education, and mandate ethnic cleansing. Before I describe a shocking set of experimental findings on dehumanization, consider first a snapshot into some of our historical attitudes, shared across many countries and cultures. Before we knew much about human evolution and the causes of variation, scientists made sweeping statements about the relationship between brain structure and differences in intelligence and behavior among men, women and the variety of races. It was commonly believed that, compared with white men, women and all other races had smaller brains, approximating our cousins the apes. Listen to Gustave LeBon, a distinguished social psychologist, writing in 1879: In the most intelligent races, as among the Parisians, there are a large number of women whose brains are closer in size to those of gorillas than to the most developed male brains. This inferiority is so obvious that no one can contest it for a moment; only its degree is worth discussion. All psychologists who have studied the intelligence of women, as well as poets and novelists, recognize today that they represent the most inferior forms of human evolution and that they are closer to children and savages tha