We are, in a way, temporary ambulatory repositories for our nucleic acids. This does not deny our humanity; it does not prevent us from pursuing the good, the true and the beautiful. But it would be a great mistake to ignore where we have come from in our attempt to determine where we are going.

What distinguishes our species is thought. The cerebral cortex is in a way a liberation. We need no longer be trapped in the genetically inherited behavior patterns of lizards and baboons: territoriality and aggression and dominance hierarchies. We are each of us largely responsible for what gets put in to our brains. For what as adults we wind up caring for and knowing about. No longer at the mercy of the reptile brain we can change ourselves. Think of the possibilities.

It's hard to kill a creature once it lets you see its consciousness.

I hold that popularization of science is successful if, at first, it does no more than spark the sense of wonder.

Except for fools and madmen, everyone knows that nuclear war would he an unprecedented human catastrophe.

Humans are very good at dreaming, although you'd never know it from your television.

There is every reason to think that in the coming years Mars and its mysteries will become increasingly familiar to the inhabitants of the Planet Earth.