“Acquaintance, n. A person whom we know well enough to borrow from, but not well enough to lend to. A degree of friendship called slight when its object is poor or obscure, and intimate when he is rich or famous”

Source: The Tenant of Wildfell Hall (1848), Ch. XXIX : The Neighbour; Helen to Walter

Letter One (17 February 1903) as translated by M. D. Herter Norton (1993)
Source: Letters to a Young Poet (1934)

Source: He's Gone

Source: Nervous Conditions

Three Centuries of Meditations and Vowes century III, LIX.

Phaedrus as translated in the novel, p. 104
The Charioteer (1953)

18
Variant translation:
It is a sad thing when men have neither the wit to speak well, nor the judgment to hold their tongues.
As quoted in A Dictionary of Thoughts: being A Cyclopedia of Laconic Quotations from the Best Authors of the World, both Ancient and Modern (1908) edited by Tryon Edwards, p. 560
Les Caractères (1688), De la société et de la conversation

Jacula Prudentum (1651)

The Provoked Wife (1698)