Good quotations, like good thoughts, are true wealth. – Annie E. Lancaster, quoted in Day’s Collacon: An Encyclopædia of Pros

Proverbs accordingly are somewhat analogous to those medical Formulas which, being in frequent use, are kept ready-made-up in the chemists’ shops, and which often save the framing of a distinct Prescription. – Richard Whately, Elements of Rhetoric

Not everything that can be extracted appears in anthologies of quotations, in commonplace books, or on the back of Celestial Seasonings boxes. Only certain sorts of extracts become quotations. – Gary Saul Morson, The Words of Others: From Quotations to Culture, 2011