The truest sayings are paradoxical. – Laozi, as quoted in The Wisdom of the East: The Sayings of Lao Tzŭ, transla

Quotation mistakes, inadvertency, expedition, and human lapses, may make not only moles but warts in learned authors… – Thomas Browne, Christian Morals, 1716 (Part the Second, sect. ii)

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