There is only one good, knowledge, and one evil, ignorance.

Logic will get you from A to Z, imagination will get you everywhere.

Anyone who has never made a mistake has never tried anything new.

The more I see, the less I know for sure.

Imagination is more important than knowledge. Knowledge is limited. Imagination encircles the world.

Where there is shouting, there is no true knowledge.

Insanity is doing the same thing over and over again and expecting different results.

Only a life lived for others is a life worthwhile.

Once we accept our limits, we go beyond them.