That's a myth. Intelligence is correlated with quite a lot of things which promote happiness. There are already sources in the thread, so I'll just mention a c

That's a myth. Intelligence is correlated with quite a lot of things which promote happiness. There are already sources in the thread, so I'll just mention a couple factors: education/work/money, and late marriage/kids. Believe it or not, but not living close to minimum wage and having children only when married and you can afford them are both huge factors of a happy life. Huge. And both are very correlated with intelligence. Now, why is this myth so widespread? Tbh, I don't really know. I can guess at availability heuristic - smart people see mostly themselves and smart people around them, see that the happiness level isn't that great, especially when young, imagine everybody else is happier so it's a reasonable conclusion that being smart is bad. The problems with this logic are that less smart/poorer people have it a lot worse, but they don't have contact with them. And also that extra education will indeed delay your earning years somewhat, so being young, not-yet-earning and smart does feel pretty bad.