Masai

Karen: I remember him. There was something...
Denys: Masai. He was half Masai.That's what you remember about him. They're like nobody else. We think we'll tame them.. but we won't. If you put them in prison, they die.
Karen: Why?
Denys: Because they live now. They don't think about the future. They can't grasp the idea that they'll be let out one day. They think it's permanent. So they die.”

Out of Africa (1985) Dir: Sydney Pollack