[B]ut in literature, it should be remembered, a thing always becomes his at last who says it best, and thus makes it his own. – James Russell Lowell

I doubt whether Cromwell or Milton could have rivaled [William Lloyd] Garrison in this field of quotation; and the power of quotation is as dreadful a weapon as any which the human intellect can forge. – John Jay Chapman

Immortality. I notice that as soon as writers broach this question they begin to quote. I hate quotation. Tell me what you know. – Ralph Waldo Emerson, Journals, May 1849

We prefer to think that the absence of inverted commas guarantees the originality of a thought, whereas it may be merely that the utterer has forgotten its source. – Clifton Fadiman, The American Treasury, 1455-1955, 1955