I have always been intrigued by people’s tendency to believe what they want to believe rather than what the facts are telling them, to believe what their innate biases desire rather than what is true. I do it myself, of course, although I hope that for the most part I manage to maintain more than a passing acquaintance with the truth. Perhaps my years of practicing engineering helped discipline my mind sufficiently.

Recently in the U.S. we have seen this tendency carried to the point not only of delusion, but of mass delusion. The mob that attacked the Capitol believed something that is clearly false, i.e. that Donald Trump won the presidential election. For that to be true, all those Republicans responsible for counting votes, and all those Republican judges who rejected Trump’s lawsuits, some appointed by Trump himself, would have to be in on the conspiracy. That would have to be some conspiracy indeed.

How can they believe such nonsense? Ostensibly because their political messiah, Donald Trump, a habitual liar, says it’s true. But really, of course, they believe it simply because they want it to be true.

Coincidentally, just at this moment of mass delusion, the Metropolitan Museum in New York has scheduled an exhibition by the 18th century Spanish artist Francisco Goya that includes a number of paintings of crowds caught up in the sort of collective delusion we have recently witnessed in Washington. The paintings perfectly capture the mass fanaticism of Trump supporters besieging the Capitol. An article in The Guardian suggests that Americans should flock to the exhibit to witness how their nation, which was a beacon of hope in Goya’s time, has sunk into the morass depicted in the great painter’s art.

President-elect Biden has promised to work toward unity of his divided nation. But can democracy deal with mass delusion? Citizens biasing their thinking toward their innate beliefs is one thing, delusion is something else. And possession by mass delusion is to occupy another world, a world of fantasy. Bias is not beyond the reach of reason, delusion is immune. To the deluded, reason simply reinforces a conviction of conspiracy.

So if Biden can unite rational Americans with the deluded masses, he will be quite a remarkable president indeed. His challenge is immense. A survey by researchers from Northeastern, Harvard, Northwestern, and Rutgers universities indicated that over half of Republican voters either believe Trump won the election or aren’t sure who did. Facing that degree of delusion, Biden will need all the luck in the world.