My success wasn't so much due to intelligence, but the fact that I stuck with problems longer.

(Reply on what constitutes scientific proof:)"The question is much too difficult for me.

The word God is for me nothing more than the expression and product of human weaknesses.

Pure mathematics is, in its way, the poetry of logical ideas. ... [By seeking] logical beauty spiritual formulas are discovered necessary for the deeper penetration into the laws of nature.

It is high time the ideal of success should be replaced with the ideal of service.

Thinking is to man what flying is to birds. Don’t follow the example of a chicken when you could be a lark.

On the left-hand side of the field equation we may add the fundamental tensor guv, multiplied by a universal constant, -λ, at present unknown, without destroying the general covariance.