PORTIUS: ‘Tis not in mortals to command success,
But we’ll do more, Sempronius; we’ll deserve it.

Joseph Addison (1672-1719) English essayist, poet, statesman

Cato, Act 1, sc. 2, l. 43ff (1713)
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This passage was widely known to America's Founders; John Adams paraphrases it in a letter to his wife Abigail (1776-02-18), and George Washington in letters to Nicholas Cooke (1775-10-29) and, most famously, Benedict Arnold (1775-12-05).