I once watched a documentary on Carl Jung once, very interesting guy. He said that he observed that people seemed the happier the larger their spiritual horizon was and less the more narrow.
I don't mean "religious" so to speak but spiritual. So even if you got some big balls off a brain if you lock yourself in your mind or the daily toils of life like economic development etc you encase yourself. Running like a hamster in a cage, chocking yourself to , but hey thatís just my experience.