To laugh often and much ... this is to have succeeded. Probably not from Emerson: here's the full quotation and the story.
Ralph Waldo EmersonWe judge of a man's wisdom by his hope, knowing that the inexhaustibleness of nature is an immortal youth.
Ralph Waldo EmersonOur faith comes in moments . . . yet there is a depth in those brief moments which constrains us to ascribe more reality to them than to all other experiences.
Ralph Waldo Emerson