The wise never marry, and when they marry they become otherwise.

If I have questions about the universe on my mind when I go to bed, I can't turn off. I dream equations all night.

Just like a computer, we must remember things in the order in which entropy increases. This makes the second law of thermodynamics almost trivial. Disorder increases with time because we measure time in the direction in which disorder increases. You can't have a safer bet than that!

Theology is unnecessary.

Over a very small number of rolls of the dice, the uncertainty principle is very important.

Sometimes I wonder if I'm as famous for my wheelchair and disabilities as I am for my discoveries.

Our population and our use of the finite resources of planet Earth are growing exponentially, along with our technical ability to change the environment for good or ill. But our genetic code still carries the selfish and aggressive instincts that were of survival advantage in the past. It will be difficult enough to avoid disaster in the next hundred years, let alone the next thousand or million. Our only chance of long term survival, is not to remain inward looking on planet Earth, but to spread out into space.