Here’s a stimulating article in Psychology Today on the subject.
I would say that a disproportionate number of us believe what we want to believe, despite compelling evidence to the contrary. That’s certainly one definitely of stupidity.
Reader Bill Baer agrees: Yes it is. To not know and not know that you don’t know is ignorance, but to not know and to think that you do know is stupidity.
It’s possible that the United States is in the process of losing its most precious asset: it’s democratic republic, as almost half of us are so dull-witted that we cannot see through the most obvious conman that the mind could possibly imagine. And if that that happens, the proximate cause will be precisely this: stupidity.