USAGE, n. The First Person of the literary Trinity, the Second and Third being Custom and Conventionality. Imbued with a decent reverence for this Holy Triad an industrious writer may hope to produce books that will live as long as the fashion.
Source: The Devil's Dictionary, 1911.
-- Ambrose Bierce, (Jun 24 1842-1914), US journalist, short-story writer; He was a noted wit, satirist and sardonic short story writer who disappeared while covering the Mexican revolution.