Disdainful of America's booming commercialism and industrialism, Henry David Thoreau left Concord, Massachusetts, in 1845 to live in solitude in the woods near Walden Pond. Walden, the account of his stay, conveys at once a naturalist's wonder at the commonplace and a Transcendentalist's yearning for spiritual truth and self-reliance. But even as Thoreau disentangled himself from worldly matters, his musings were often disturbed by his social conscience....