History warns us that it is the customary fate of new truths to begin as heresies and to end as superstitions.

Common sense is science exactly in so far as it fulfills the ideal of common sense; that is, sees facts as they are, or at any rate, without the distortion of prejudice, and reasons from them in accordance with the dictates of sound judgment. And science is simply common sense at its best, that is, rigidly accurate in observation, and merciless to fallacy in logic.

Action is the catalyst that creates accomplishments. It is the path that takes us from uncrafted hopes to realized dreams.

I care not what subject is taught, if only it be taught well.

We live in a world which is full of misery and ignorance, and the plain duty of each and all of us is to try to make the little corner he can influence somewhat less miserable and somewhat less ignorant than it was before he entered.

To quarrel with the uncertainty that besets us in intellectual affairs would be about as reasonable as to object to live one's life with due thought for the morrow because no man can be sure he will alive an hour hence.

Whatever part of the animal fabric whatever series of muscles, whatever viscera might be selected for comparison the result would be the same the lower Apes and the Gorilla would differ more than the Gorilla and the Man.