“Do what nature now requires. Set thyself in motion, if it is in thy power, and do not look about thee to see if any one will observe it; nor yet expect Plato's Republic: but be content if the smallest thing goes on well, and consider such an event to be no small matter.”
Forward, as occasion offers. Never look round to see whether any shall note it…. Be satisfied with success in even the smallest matter, and think that even such a result is no trifle.
IX, 29
Meditations (c. 121–180 AD), Book IX
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Marcus Aurelius 400
Emperor of Ancient Rome 121–180Related quotes

Source: The Temple (1633), The Elixir, Lines 1-4

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Epigram.
Bartlett's Familiar Quotations, 10th ed. (1919)

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Sonnet, The Story of Justin Martyr and Other Poems; reported in Hoyt's New Cyclopedia Of Practical Quotations (1922), p. 190-92.

Reported in Josiah Hotchkiss Gilbert, Dictionary of Burning Words of Brilliant Writers (1895), p. 433.