Henry David Thoreau, writer and philosopher:

“If you have built castles in the air, your work need not be lost, that is where they should be. Now put foundations under them.”

George Bernard Shaw, playwright:

“You see things and you say ‘Why?’ But I dream things that never were and I say ‘Why not?‘”

Michelangelo, Renaissance polymath:

“I saw the angel in the marble and carved until I set him free.”