Self-confidence. I can see it on my relatives. The dumbest ones are usually the most cocksure, and while this leads the wrong decisions occasionally, it really keeps them free from worry and as such free from much stress. They sleep well. The funny part is that it leads to wrong decision far less often than I would expect to. While they are sure of themselves, they somehow still keep wisely out of things they know nothing about so they don't invest their money in industries they don't understand and so on. This is sort of difficult to map for me. I think their cocksurety is largely about thinking they are good about things they are really experienced about. They understand wandering out of their area of expertise would be dangerous. They identify with what they did so far, identify with their profession, have this I-am-good confidence, but also the attitude that I-am-a-bricklayer and understand they would know very little outside bricklaying, but since they identify with what they do, they are cocksure inside that domain. Everything else they are simply not interested in. Does that even make sense? Basically less intelligent people being less curious so less bothered by things they don't know outside their domain, and thus knowing their domain well enough makes them confident enough, does that even make sense?