To laugh often and much ... this is to have succeeded. Probably not from Emerson: here's the full quotation and the story.
Ralph Waldo EmersonWhat art can paint or gild any object in after life with the glow which nature gives to the first baubles of childhood? St. Peter's cannot have the magical power over us that the red and gold covers of our first picture-book possessed.
Ralph Waldo EmersonIf we could have any security against moods! If the profoundest prophet could be holden to his words, and the hearer who is readyto sell all and join the crusade, could have any certificate that to-morrow his prophet shall not unsay his testimony!
Ralph Waldo EmersonThere is some awe mixed with the joy of our surprise, when this poet, who lived in some past world, two or three hundred years ago, says that which lies close to my own soul, that which I also had wellnigh thought and said.
Ralph Waldo Emerson