In these circumstances I think we must take the bull by the horns… and, making due allowances, quote whenever we feel that the allusion is interesting or helpful or amusing. – Clifton Fadiman, c.1955

QUOTATION, n. The act of repeating erroneously the words of another. The words erroneously repeated. – Ambrose Bierce, The Devil’s Dictionary

The more an idea is developed, the more concise becomes its expression: the more a tree is pruned, the better is the fruit. – Alfred Bougeart, quoted in A Thousand Flashes of French Wit, Wisdom, and Wickedn

The mind will quote whether the tongue does or not. – Attributed to Emerson in Edge-Tools of Speech by Maturin M. Ballou, 1886