We should take care not to make the intellect our god; it has, of course, powerful muscles, but no personality.

If something is in me which can be called religious then it is the unbounded admiration for the structure of the world so far as our science can reveal it.

To be sure, it is not the fruits of scientific research that elevate a man and enrich his nature, but the urge to understand, the intellectual work, creative or receptive.

The consequence was a positively fanatic [orgy of] freethinking coupled with the impression that youth is being deceived by the state through lies; it was a crushing impression

The main task of the spirit is to free man from his ego.

Since the mathematicians have invaded the theory of relativity I do not understand it myself any more.

You ask me if I keep a notebook to record my great ideas. I've only ever had one.