"Our imagination is stretched to the utmost, not, as in fiction, to imagine things which are not really there, but just to comprehend those things which are there."

"I don't think I'm a very good teacher. I just try to explain things clearly."

"I would rather have a world with five billion people that are happy and healthy and well-fed and full of wonderful things than a world with twenty billion people who are starving and miserable."

"I was always interested in things that are on the edge of what we know."

"People would often think I'm a faker, but I'm usually honest, in a certain way- in such a way that often nobody believes me!"