I suspect one significant factor is simply that intelligent well-informed people are aware of how much folly and unnecessary harm there is in the world, while less intelligent and more ignorant people remain blithely unaware. Intelligent people actually need more substantive human contact because they are unlikely to be satisfied gawping at some TV show or twitching frantically over a game console, but there are only a small number of equally thoughtful people out there because IQ has a Gaussian distribution.

And, finally, as we’re all supposed to pretend that everyone is equally “intelligent” because otherwise less intelligent folk might feel upset, it’s important never to talk or write about intelligence. If you do, the inevitable and always banal cliched responses will roll predictable in.