"I am enough of an artist to draw freely upon my imagination. Imagination is more important than knowledge. Knowledge is limited. Imagination encircles the world."

"The most beautiful experience we can have is the mysterious. It is the fundamental emotion which stands at the cradle of true art and true science."

"The word God is for me nothing more than the expression and product of human weaknesses."

"The value of a man should be seen in what he gives and not in what he is able to receive."

"The important thing is not to stop questioning. Curiosity has its own reason for existence."