“When a thing has been said, and said well, have no scruple. Take it and copy it.” (Anatole France)
“One of the surest of tests is the way in which a poet borrows. Immature poets imitate; mature poets steal; bad poets deface what they take, and good poets make it into something better, or at least something different. The good poet welds his theft into a whole of feeling which is unique, utterly different from that from which it was torn; the bad poet throws it into something which has no cohesion.”
T.S. Eliot, in The Sacred Wood: Essays on Poetry and Criticism, Chapter on Philip Massinger
Anyone tempted to take the attribution of aphorisms and well-known sayings too seriously should read Nice Guys Finish Seventh: False Phrases, Spurious Sayings, and Familiar Misquotations, by Ralph Keyes. This book is unfortunately out of print. Keyes’ rules of misquotation are:
Axiom 1. Any Quotation That Can Be Altered Will Be.
Corollary 1A: Vivid words hook misquotes in the mind.
Corollary 1B: Numbers are hard to keep straight.
Corollary 1C: Small changes can have a big impact (or: What a difference an A makes).
Corollary 1D: If noted figures don’t say what needs to be said, we’ll say it for them.
Corollary 1E: Journalists are a less than dependable source of accurate quotes.
Corollary 1F: Famous dead people make excellent commentators on current events.
Axiom 2. Famous Quotes Need Famous Mouths.
Corollary 2A: Well-known messengers get credit for clever comments they report from less celebrated mouths.
Corollary 2B: Particularly quotable figures receive more than their share of quotable quotes.
Corollary 2C: Comments made about someone might as well have been said by that person.
Corollary 2D: Who you think said something may depend on where you live.
Corollary 2E: Vintage quotes are considered to be in the public domain.
Corollary 2F: In a pinch, any orphan quote can be called a chinese proverb.