You can mass-produce hardware; you cannot mass-produce software - you cannot mass-produce the human mind.

In science, nothing is ever 100% proven.

I want to see us to explore outer space. But I want to do it safely, without the loss of human life, and democratically: where is the free-wheeling debate on this question? Only one force can stop this mission: the will of the American people. They have not been asked. Do they want to endanger their loved ones, their industry with this launch? One force is more powerful than plutonium, the spirit of the American people united.

I believe that science is the engine of prosperity, that if you look around at the wealth of civilization today, it's the wealth that comes from science.

The most complex object in the known universe: brain, only uses 20 watts of power. It would require a nuclear power plant to energize a computer the size of a city block to mimic your brain, and your brain does it with just 20 watts. So if someone calls you a dim bulb, that's a compliment.

Chances are, when we meet intelligent life forms in outer space they're going to be descended from predators.

What is the universe? The universe is a symphony of vibrating strings...we are nothing but melodies. We are nothing but cosmic music played out on vibrating strings and membranes.