Laws alone cannot secure freedom of expression; in order that every man present his views without penalty there must be a spirit of tolerance in the entire population.

Ethical axioms are found and tested not very differently from the axioms of science. Truth is what stands the test of experience.

The most incomprehensible thing about the world is that it is comprehensible.

Imagination is more important than knowledge.

Neither can I believe that the individual survives the death of his body, although feeble souls harbour such thoughts through fear or ridiculous egotism.

I want to know God's thoughts ... the rest are details.

There are only two ways to live your life. One is as though nothing is a miracle. The other is as though everything is a miracle.

The most beautiful experience we can have is the most mysterious ... He to whom the emotion is a stranger, who can no longer pause and stand wrapped in awe, is as good as dead; his eyes are closed.

When I study philosophical works I feel I am swallowing something which I don't have in my mouth.

Concern for man and his fate must always form the chief interest of all technical endeavours. Never forget this in the midst of your diagrams and equations.