The dark psychology of dehumanization, explained
http://www.vox.com/science-and-health/2017/3/7/14456154/dehumanization-psychology-explained
Thousands of years ago, humans would have felt a pang of anxiety when they saw the silhouette of a foreign tribe marching over a hill. We still have that anxiety inside of us today. Often peoples spontaneous, knee-jerk reactions to other people who are dramatically different from them is negative, says Susan Fiske, a psychologist at Princeton University and a leading expert on prejudice. This is especially true when we have quick, minimal exposure to them as we do today via the media. These thin slices activate the us-versus-them conflict encoded in our minds since the dawn of humanity.
Look back at some of the most tragic episodes in human history and you will find words and images that stripped people of their basic human traits. In the Nazi era, the film The Eternal Jew depicted Jews as rats. During the Rwandan genocide, Hutu officials called Tutsis cockroaches that needed to be cleared out.
In the wake of World War II, psychologists wanted to understand how the genocide had happened. And we got Stanley Milgrams infamous electroshock experiment, which showed how quickly people cave to authority. There was also Philip Zimbardos prison experiment, which showed how easily people in positions of power can abuse others. At Stanford, Albert Bandura, showed that when participants overhear an experimenter call another study subject an animal, theyre more likely to give that subject a painful shock. If you think of murder and torture as universally taboo, then dehumanization of the other is a psychological loophole that can justify them.