We assume that evil arises out of contempt, misplaced pride, or even mental disorders, but we are wrong. Decency and evil are not mutually exclusive. In fact, the greatest atrocities require masses of decent people.

In 1961 philosopher Hannah Arendt attended the trial of Adolf Eichmann, a man who helped carry out the Holocaust genocide. He was responsible for unspeakable horror. Yet, as Arendt observed, Eichmann was not a vicious or menacing monster. He wasn’t snarling and spewing hate. He was normal—a “half a dozen psychiatrists” had even certified it. He was like anyone you might pass on the street or sit next to on a bus. She writes that “he personally never had anything whatever against the Jews,” yet he oversaw their systematic execution with no compunction. “The deeds [of Eichmann] were monstrous, but the doer…was quite ordinary, commonplace, and neither demonic nor monstrous. There was no sign in him of firm ideological convictions or of specific evil motives.”

In our age of complex bureaucracies, so much cruelty is simply the result of normal, everyday, “real” people doing what they think is most pragmatic. As the philosopher Bernard Williams said, “the modern world…has made evil, like other things, a collective enterprise.” Eichmann was not the personification of hatred. His motives were banal. Evil is often the result of small, procedural things. It is people doing their jobs and remaining loyal to their parties, regardless of evidence, arguments, or troubling historical parallels.

Yet surely Eichmann was not a decent person, you might think. But what distinguishes his character from our own? Adolf Eichmann was a normal man. The circumstances he was in, however, were abnormal. There are many of us who would fail just like Eichmann, but because we have never faced such an impactful moral choice, we get to be counted as decent. We are simply lucky that our moral character has not, up until this point, been tested in profound ways. Do we actually deserve to think of ourselves as better than Eichmann? We know there is a difference in circumstance. Do we know that there is a difference in character?

The traditional view of evil is attractive because it exonerates us normal people; we can feel comfortable in our decency. While we implicitly praise ourselves through that error, we fail to assess our own choices and character honestly. We caricature evil as something that only comes from people with rotten souls, so when we think about evil, we envision something that by definition excludes us.

Arendt finds thoughtlessness—which is different from stupidity—at the root of the banality of evil. It stems from a failure to think and empathize. “The longer one listened to [Eichmann], the more obvious it became that his inability to speak was closely connected with an inability to think, namely, to think from the standpoint of somebody else,” she said. When we examine the basic principles or arguments from which evil comes, we find nothing there. Instead we find mediocrity, myopic pragmatic concerns, and understandable intentions.

Thoughtlessness makes group membership more important than ideas. In other words, whether a policy is wise or an argument valid depends not on the policy or argument, but on the source. If the source is my group, it is wise and good. If the source is the enemy, then it is evil. A brute tribalism—defined either in terms of political party, race, religion, or national origin—dilutes public life into a series of simplistic moral judgments, all of which reduce to one: good vs. evil.

This sets critical thinking, honest self-reflection, and historical perspective as the antidote. It pushes us to reevaluate our loyalties. Arendt noticed that Eichmann frequently repeated clichés; they had replaced thought. It is easy to mark our territory with a hashtag or retreat to the normal political battle stations when we hear rumors of stories. Consider the clichés that dominate our political discussions—the practiced partisan responses that give the appearance of passionate debate. How often do we know why we hold the views we do?

We must take stock of our core commitments and be open to changing them. Group membership is convenient because it allows us to skip genuine critical thought. As the group drifts, we drift with it—maybe into a truly dark place. And when we wonder how it happened, we look inside to find countless decent people repeating banalities. We are simply lucky that, until now, the dominant governing groups have not drifted into those truly dark places. When they do, plenty of us will follow.

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