A main fact in the history of manners is the wonderful expressiveness of the human body. If it were made of glass, or of air, and the thoughts were written on steel tablets within, it could not publish more truly its meaning than now. Wise men read very sharply all your private history in your look and gait and behavior. The whole economy of nature is bent on expression. The telltale body is all tongues.

Ralph Waldo Emerson
Ralph Waldo Emerson (1803-1882) American essayist, lecturer, poet
Essay (1860), “Behavior,” The Conduct of Life, ch. 5
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Based on a course of lectures by that name first delivered in Pittsburg (1851-03).