Remember that there is nothing noble in being superior to some other man. The true nobility is in being superior to your previous self.

W. L. Sheldon (1858-1907) American lecturer, ethicist [Walter Lorenzo Sheldon]

“What to Believe: An Ethical Creed,” Ethical Addresses (Apr 1897)
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Often incorrectly attributed to Hemingway. More discussion: There Is Nothing Noble in Being Superior to Some Other Man. The True Nobility Is in Being Superior to Your Previous Self – Quote Investigator.