It is humankind's duty to respect all life, not only animals have feelings but even also trees and plants.

The idea of a personal God is quite alien to me and seems even naïve.

If I can't picture it, I can't understand it.

I don't believe in mathematics.

You ask me if I keep a notebook to record my great ideas. I've only ever had one.

Thinking is to man what flying is to birds. Don’t follow the example of a chicken when you could be a lark.

Every day, man is making bigger and better fool-proof things, and every day, nature is making bigger and better fools. So far, I think nature is winning.