Walking the streets of Tokyo with Hawking in his wheelchair ... I felt as if I were taking a walk through Galilee with Jesus Christ [as] crowds of Japanese silently streamed after us, stretching out their hands to touch Hawking's wheelchair. ... The crowds had streamed after Einstein [on Einstein's visit to Japan in 1922] as they streamed after Hawking seventy years later. ... They showed exquisite choice in their heroes. ... Somehow they understood that Einstein and Hawking were not just great scientists, but great human beings.

Younger people have so many opportunities. I don't see any pessimism among them.

[John Wheeler] rejuvenated general relativity; he made it an experimental subject and took it away from the mathematicians

The technologies which have had the most profound effects on human life are usually simple. A good example of a simple technology with profound historical consequences is hay. ... It was hay that allowed populations to grow and civilizations to flourish among the forests of Northern Europe. Hay moved the greatness of Rome to Paris and London, and later to Berlin and Moscow and New York.

Most of the papers which are submitted to the Physical Review are rejected, not because it is impossible to understand them, but because it is possible. Those which are impossible to understand are usually published.

Now, as Mandelbrot points out, ... Nature has played a joke on the mathematicians. The 19th-century mathematicians may not have been lacking in imagination, but Nature was not. The same pathological structures that the mathematicians invented to break loose from 19th-century naturalism turn out to be inherent in familiar objects all around us.

We do not know how much of the environmental change is due to human activities and how much [is due] to long-term natural processes over which we have no control.