A human being should beware how he laughs, for then he shows all his faults.

All history is but the lengthened shadow of a great man.

I should as soon think of swimming across Charles River, when I wish to go to Boston, as of reading all my books in originals, when I have them rendered for me in my mother tongue.

Health is the first muse, and sleep is the condition to produce it.

I do not hesitate to read. all good books in translations. What is really best in any book is translatable-any real insight or broad human sentiment.

One definition of man is an intelligence served by organs.

All science has one aim, namely, to find a theory of nature.