"why are the stupid still here?", well that depends on many things. For starters what would you specifically define as "stupid"? And why do you feel that they shouldn't be here? We are all here because of millions of years of evolution taking place at the genetic level. Why would your degree of intelligence make a difference so long as you find a way to survive? I don't understand why so many of you are treating this theory as some sort of subjective force that chooses who/what can evolve or can differentiate between something that is "stupid" or something that is intelligent. It is just something that happens, it is not a "law", it was not created and cannot be controlled or stopped or hindered, it is just an objective explanation for a series of scientific observations.
More to the point, intelligence itself is more based on nurture than nature. The dumbest idiot can have a genius child and the most genius of men can have an idiot for a son. The "stupid" are still here because after millions of years of evolution, their biological systems have developed the capacity to survive in this world, whether or not they maximise their potential is irrelevant to survival because evolution has already granted them with the ability to survive.
What I'm trying to say is, it's not that the "stupid" are stupid, the stupid are normal and fit to survive, its just that others are relatively smarter.
More to the point, intelligence itself is more based on nurture than nature. The dumbest idiot can have a genius child and the most genius of men can have an idiot for a son. The "stupid" are still here because after millions of years of evolution, their biological systems have developed the capacity to survive in this world, whether or not they maximise their potential is irrelevant to survival because evolution has already granted them with the ability to survive.
What I'm trying to say is, it's not that the "stupid" are stupid, the stupid are normal and fit to survive, its just that others are relatively smarter.