If you can't explain it simply, you don't understand it well enough.

I am a Jew, but I am enthralled by the luminous figure of the Nazarene….No one can read the Gospels without feeling the actual presence of Jesus.

My pacifism is not based on any intellectual theory but on a deep antipathy to every form of cruelty and hatred.

Overemphasis of the competitive system and premature specialization on the ground of immediate usefulness kill the spirit on which all cultural life depends, specialized knowledge included.

You teach me baseball and I'll teach you relativity...No we must not. You will learn about relativity faster than I learn baseball.

Imagination rules the earth

Science will stagnate if it is made to serve practical goals.