Im not smart (maybe average), but a lot of my unhappiness starts from just having access to information. And then more I process the information, the more unhappy I become. Smarter people than me probably have more information and are able to process it faster, uncovering effects that are not readily perceived by normal folks like myself.
While my intelligence is ~ constant, my levels of happiness fluctuated during my life and now, at 48, I am maybe twice as happy as I was at 24. There is definitely an upward trend with me...
During the same period, I also absorbed a lot of information, including some ghastly one. And yet my overall feeling of well-being improved.
IDK what happened, I can at best describe it as if "someone slowly changed the lens I am using to view the world for a less cloudy one".
Maybe some sort of hormonal development. It seems to be outside my will, though. Just happened.