Acquaintance, n. A person whom we know well enough to borrow from, but not well enough to lend to.

-Bierce, Ambrose Gwinett
  The Cynic's Word Book. Retitled  The Devil's Dictionary (1911).

Great poetsseldommake bricks without straw.They pile up allthe excellencestheycanbeg, borrow, or steal from their predecessors and contemporaries and then set their own inimitable light atop the mountain.

-Pound, Ezra Loomis
Quoted in Patricia C Willis (ed) The Complete Poems of Marianne Moore (1986).