Have the courage to be ignorant of a great number of things, in order to avoid the calamity of being ignorant of everything.
Source: In Instant Quotation Dictionary, by Donald O. Bolander, 1979.
-- Sydney Smith, (Jun 6 1771-1845), English clergyman, essayist; He was a leading preacher of his day who championed Catholic emancipation in Letters of Peter Plymley, 1807.