The great end of life is not knowledge but action.
Make up your mind to act decidedly and take the consequences. No good is ever done in this world by hesitation.
Try to learn something about everything and everything about something.
Time is not a thing, thus we can neither waste nor save it; it is always with us.
The chess-board is the world; the pieces are the phenomena of the universe; the rules of the game are what we call the laws of Nature.
Sit down before fact as a little child, be prepared to give up every preconceived notion, follow humbly wherever and to whatever abysses nature leads, or you shall learn nothing.
The known is finite, the unknown infinite; intellectually we stand on an islet in the midst of an illimitable ocean of inexplicability.
Every great advance in natural knowledge has involved the absolute rejection of authority.
The improver of natural knowledge absolutely refuses to acknowledge authority as such.
Science is simply common sense at its best—that is, rigidly accurate in observation, and merciless to fallacy in logic.
Logical consequences are the scarecrows of fools and the beacons of wise men.
It is not what we believe, but why we believe it; moral responsibility begins there.
The saying that a little knowledge is a dangerous thing is, to my mind, a very dangerous adage.
The great tragedy of Science—the slaying of a beautiful hypothesis by an ugly fact.
Patience and tenacity of purpose are worth more than twice their weight of cleverness.
Eager and intense desire is the mainspring of all effective effort.
Freedom and order are not incompatible; truth is strength; free discussion is the very life of truth.
That man, I think, has had a liberal education who has been so trained in youth that his body is the ready servant of his will.
The most considerable difference I can see between men and animals is not in reason, but in the extent of the power of using it.
No one is altogether to be blamed for the defects of his nature; but he is blameworthy if he takes no pains to correct them.