They who know of no purer sources of truth, who have traced up its stream no higher, stand, and wisely stand, by the Bible and the Constitution, and drink at it there with reverence and humility; but they who behold where it comes trickling into this lake or that pool, gird up their loins once more, and continue their pilgrimage toward its fountain-head.
Henry David Thoreau (1817–1862), U.S. philosopher, author, naturalist. "Civil Disobedience," originally published as "Resistance to Civil Government" (1849), in The Writings of Henry David Thoreau, vol. 4, pp. 385-386, Houghton Mifflin (1906).