A perfection of means, and confusion of aims, seems to be our main problem.

I do not play games. There is not time for it. When I get through with work, I don't want anything that requires the working of the mind.

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.

Intelligence is not the ability to store information, but to know where to find it.

Formerly, people thought that if matter disappeared from the universe, space and time would remain. Relativity declares that space and time would disappear with matter.

The more success the quantum theory has, the sillier it looks

The opinion prevailed among advanced minds that it was time that belief should be replaced increasingly by knowledge; belief that did not itself rest on knowledge was superstition, and as such had to be opposed.