It's not necessarily "dark" in the sense that human beings are programmed to always look for betterment for a reason. If human beings didn't have this drive to

It's not necessarily "dark" in the sense that human beings are programmed to always look for betterment for a reason. If human beings didn't have this drive to always do better and get more, we definitely wouldn't have the highly developed modern society that we have nowadays, with broadly speaking the best living conditions in history. Of course there are people who argue that the hunter-gatherers might well have been happier in some aspects, but the point is even they didn't think differently: A tribe living in an area with abundant resources might still always dream of greener pastures. One should definitely learn to strike a balance between wanting more and enjoying what they have, though my point is that to totally label such thoughts "dark" doesn't sound fair to me. If human beings lose this drive altogether, we'd be in for very dangerous times with nobody having the ambition to strive and improve anything.