"It’s all happened already. Back there in the past, ten thousand years ago. The man of the future, with the big brain, the small teeth. He lived in Africa. His brain was bigger than your brain. His face was straight and small, almost a child’s face."
"Maybe all that thoughtfulness was of no particular survival value in 10,000 B.C. The great genius of civilization is that it allows individuals to store memory and operating rules outside of their brains, in the world that surrounds them. The human brain is a sort of central processing unit operating on multiple memory disks, some stored in the head, some in the culture. Lacking the external hard drive of a literate society, the Boskops were unable to exploit the vast potential locked up in their expanded cortex. They were born just a few millennia too soon."