“Over the course of history—during the Holocaust, the Rwandan genocide or the street beatings that happen in American neighborhoods—the same pattern has emerged,” he writes. “Many people do not intervene. Very often they see but they don’t see.”

Psychologists have studied the reasons, Brooks writes. Some people simply don’t process a horrible event because of Normalcy Bias—in which people simply shut down and pretend everything is normal. Another reason is Motivated Blindness—in which people don’t see things that are upsetting to them. He cites one experiment in which people who are uncomfortable with sex were shown pictures with sexual content. The uncomfortable folks didn’t focus on the sexual images.

Interesting work from ABA Journal from David Brooks.