Conquer the world by intelligence, and not merely by being slavishly subdued by the terror that comes from it.

Your writing is never as good as you hoped; but never as bad as you feared.

Something of the hermit's temper is an essential element in many forms of excellence, since it enables men to resist the lure of popularity, to pursue important work in spite of general indifference or hostility, and arrive at opinions which are opposed to prevalent errors.

Dogma demands authority, rather than intelligent thought, as the source of opinion; it requires persecution of heretics and hostility to unbelievers; it asks of its disciples that they should inhibit natural kindliness in favor of systematic hatred.

Calculus required continuity, and continuity was supposed to require the infinitely little; but nobody could discover what the infinitely little might be.

Politics is largely governed by sententious platitudes which are devoid of truth

A world full of happiness is not beyond human power to create; the obstacles imposed by inanimate nature are not insuperable. The real obstacles lie in the heart of man, and the cure for these is a firm hope, informed and fortified by thought.