“So what does all this mean if you desperately want to persuade someone who doesn’t want to be persuaded?

The first step is to appreciate that your opponent’s opinion is likely based less on fact and logic than on ideology and herd thinking. If you were to suggest this to his face, he would of course deny it. He is operating from a set of biases he cannot even see. As the behavioral sage Daniel Kahneman has written: “We can be blind to the obvious, and we are also blind to our blindness.” Few of us are immune to this blind spot. That goes for you, and that goes for the two of us as well. And so, as the basketball legend-cum-philosopher Kareem Abdul-Jabbar once put it, “It’s easier to jump out of a plane—hopefully with a parachute—than it is to change your mind about an opinion.”