“If I were not a Jew I would be a Quaker.”

“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.”

“If I had known they were going to do this, I would have become a shoemaker.”

“When I am judging a theory, I ask myself whether, if I were God, I would have arranged the world in such a way.”

“If I were not a physicist, I would probably be a musician. I often think in music. I live my daydreams in music. I see my life in terms of music.”

“If my theory of relativity is proven successful, Germany will claim me as a German and France will declare me a citizen of the world. Should my theory prove untrue, France will say that I am a German, and Germany will declare that I am a Jew.”

“If we knew what it was we were doing, it would not be called research, would it?”