It is not what the man of science believes that distinguishes him, but how and why he believes it. His beliefs are tentative, not dogmatic; they are … - Bertrand Russell

It is easy in the world to live after the world's opinion; it is easy in solitude to live after your own; but the great man is he who in the midst of the crowd keeps with perfect sweetness the independence of solitude.

I resolved from the beginning of my quest that I would not be misled by sentiment and desire into beliefs for which there was no good evidence.

The true spirit of delight, the exaltation, the sense of being more than Man, which is the touchstone of the highest excellence, is to be found in mathematics as surely as in poetry.