We often say that the earth is a sphere, but to be precise, the term sphere refers only to the surface. The correct mathematical term for the solid earth is a ball.

You have to say now that space is something. Space can vibrate, space can fluctuate, space can be quantum mechanical, but what the devil is it?

[Richard Feynman] truly believed that if you couldn't explain something simply, you didn't understand it.

I did not come from an academic background. My father was a smart man, but he had a fifth-grade education. He and all his friends were plumbers. They were all born around 1905 in great poverty in New York City and had to go to work when they were 12 or 13 years old.

I'm afraid I am a bit of a technophobe - a nineteenth-century man caught in the twenty-first century. But there is one piece of technology that I would especially welcome: a device to automatically balance restaurant tables on all four legs so that they don't rock back and forth.

Unforeseen surprises are the rule in science, not the exception. Remember: Stuff happens.

I was from a poor Jewish family in the South Bronx. My father was a plumber, but when I was 16, he got sick and I had to take over. Being a plumber in the South Bronx wasn't fun.