Dr. [Richard] Bentley’s son reading a novel, the Doctor said, “Why read a book which you cannot quote?” – Walpoliana (Horace Walpole, John Pinkerton), “Useless Reading,” January 1800

Nevertheless, a maxim does not necessarily become a proverb. Many grubs never grow to butterflies; and a maxim is only a proverb in its caterpillar stage—a candidate for a wider sphere and longer flight than most are destined to attain. – “Proverbs Secular and Sacred,” The North British Review, February 1858

Cunning authors cut to be quoted. – Willis Goth Regier, Quotology, 2010

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