The man who does not laugh, like the man who does not make faces, is already a buffoon at heart.
 Friedrich Nietzsche, Thus Spoke Zarathustra (1891). copy citation

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Author Friedrich Nietzsche
Source Thus Spoke Zarathustra
Topic heart laugh
Date 1891
Language English
Reference
Note Translated By Thomas Common
Weblink http://www.gutenberg.org/files/1998/1998-h/1998-h.htm

Context

“he says, and his final command to the higher men is, “LEARN, I pray you—to laugh.” All that is GOOD, in Nietzsche’s sense, is cheerful. To be able to crack a joke about one’s deepest feelings is the greatest test of their value. The man who does not laugh, like the man who does not make faces, is already a buffoon at heart. “What hath hitherto been the greatest sin here on earth? Was it not the word of him who said: ‘Woe unto them that laugh now!’ Did he himself find no cause for laughter on the earth? Then he sought badly.” source