There is an organic affinity between joyousness and tenderness.

A great idea goes through three stages on its way to acceptance: 1) it is dismissed as nonsense, 2) it is acknowledged as true, but insignificant, 3) finally, it is seen to be important, but not really anything new.

Habit is the enormous flywheel of society, its most precious conservative agent. There is no more miserable human being than one in whom nothing is habitual but indecision. Full half the time of such a man goes to the deciding, or regretting, of matters which ought to be so ingrained in him as practically not to exist for his consciousness at all.

Metaphysics means nothing but an unusually obstinate effort to think clearly.

Most men have a good memory for facts connected with their own pursuits.

It is so human a book that I don't see how belief in its divine authority can survive the reading of it.

It is astonishing how many mental operations we can explain when we have once grasped the principles of association