So here is the question. Why should feeling that you exist—and valuing the feeling—be biologically adaptive, so that the underlying brain circuits would have been selected in the course of evolution?
I believe the answer (at least the beginning of an answer) is right there in front of us. It is that a creature who takes pleasure in the feeling of existence will develop “a will to exist” and so, at least as we see it in humans, “a will to live.
— Humphrey, Nicholas. Soul Dust: The Magic of Consciousness. Princeton, New Jersey: Princeton University Press, 2011.
