Bite your tongue. Get a cinder in your eye. When you feel good, you feel nothing.

You can never learn less; you can only learn more. The reason I know so much is because I have made so many mistakes.

People should think things out fresh and not just accept conventional terms and the conventional way of doing things.

Every time man makes a new experiment he always learns more. He cannot learn less.

No man can prove upon awakening that he is the man who he thinks went to bed the night before, or that anything that he recollects is anything other than a convincing dream.

Racism, pollution and the rest of it are themselves very close to extinction.

There is nothing in a caterpillar that tells you it's going to be a butterfly.