There was a survey done a few years ago that affected me greatly. it was discovered that intelligent people either estimate their intelligence accurately or slightly underestimate themselves, but stupid people overestimate their intelligence and by huge margins. (And these were things like straight up math tests, not controversial IQ tests.)
Harvey PekarI met Robert Crumb in 1962; he lived in Cleveland for a while. I took a look at his stuff. Crumb was doing stuff beyond what other writers and artists were doing. It was a step beyond Mad.
Harvey Pekar