A great thought begins by seeing something differently, with a shift of the mind's eye.

All means prove but blunt instruments, if they have not behind them a living spirit.

Rejoice with your family in the beautiful land of life.

In theory, theory and practice are the same. In practice, they are not.

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

In my personal experience I have hardly come to know the wretchedness of mankind better than as a result of the general theory of relativity and everything connected to it. But it doesn't bother me.

It stands to the everlasting credit of science that by acting on the human mind it has overcome man's insecurity before himself and before nature.