Dietrich Bonhoeffer was executed by the Nazis in 1945. He had tried to understand why the Germans had let Hitler come to power, and he concluded that stupidity was more to blame than evil.

Stupidity is a more dangerous enemy of the good than malice. One may protest against evil; it can be exposed and, if need be, prevented by use of force. Evil always carries within itself the germ of its own subversion in that it leaves behind in human beings at least a sense of unease. Against stupidity we are defenseless. Neither protests nor the use of force accomplish anything here; reasons fall on deaf ears; facts that contradict one’s prejudgment simply need not be believed — in such moments the stupid person even becomes critical — and when facts are irrefutable they are just pushed aside as inconsequential, as incidental. In all this the stupid person, in contrast to the malicious one, is utterly self-satisfied and, being easily irritated, becomes dangerous by going on the attack. For that reason, greater caution is called for than with a malicious one. Never again will we try to persuade the stupid person with reasons, for it is senseless and dangerous.

Hanlon’s Razor puts it more concisely: “Never attribute to malice what can be reasonably explained by stupidity.”

This goes a long way to explaining the current state of America. Do millions of Americans really want a president who has expressed his intent to be a dictator? Or are they just stupid? If so, why are they stupid about him?

“Stupidity” (“Dummheit” in the original German) doesn’t mean low intelligence. It means the learned inability to think on certain topics. A person can be a sharp thinker on some things and stupid on others. Such people present a special challenge to writers who want to persuade by reason. Schiller wrote, “Mit der Dummheit kämpfen Götter selbst vergebens” (against stupidity, even gods fight in vain). Can we do any better than the gods?

Some things clearly don’t work. A lot of people apparently believe that insults are the most effective way to change people’s minds; at least they use that technique a lot. That’s itself a form of stupidity. According to Bonhoeffer, what’s necessary is the “inner freeing” of people, but that’s not something other people can do for them. The most we can do is make other modes of thinking attractive to them. Calling them names doesn’t accomplish that. Pushing them into their echo chambers doesn’t accomplish that.

It would be nice if I could claim success with other methods. I’m not good at getting people to change their minds. I’m too impatient. But I know that part of it is understanding how they think. You have to know the foundation on which they build. More often than not, it’s something which is good by itself but may be twisted in bad ways. It could be a wish for a secure life, a belief in fairness, a fear of being controlled by others, a desire to be successful and prosperous. When they regularly hear that someone will offer them these things, they believe it. They want to believe it so strongly that they reject all evidence that it’s a lie or that the person making the claim is promoting horrible goals.

A Web search on “overcoming stupidity” finds lots of results on how to overcome one’s own stupidity, but little useful advice on how to address it in others. All I’m sure of is that calling people stupid to their face, satisfying as it is, doesn’t work. Of course, it doesn’t hurt to be alert for stupidity in ourselves and avoid it.