Intelligence is no measure of a man's worth.
Anyone may have such a dubious quality, by accident of birth.
Fitness for survival may better be measured in worldview, and general outlook.
What use is a person?
From what I have seen of so-called 'intelligent' people, the world, at large, might be better off without them.
Rather a happy serf, serving something greater than himself, than a whining, scheming, calculating jackass.