Adhere to your own act, and congratulate yourself if you have done something strange and extravagant and broken the monotony of a decorous age. It was a high counsel that I once heard given to a young person, — “Always do what you are afraid to do.”

Ralph Waldo Emerson (1803-1882) American essayist, lecturer, poet

Essay (1841), “Heroism,” Essays: First Series, No. 8
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Some sources start with "Be true to ...." See also Schmich.