The only true wisdom is in knowing you know nothing.

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 greatest enemy of knowledge is not ignorance, it is the illusion of knowledge.

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

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

The most important knowledge is that which guides the way you lead your life.

Only a life lived for others is a life worthwhile.

Once we accept our limits, we go beyond them.