In his own day, Henry David Thoreau was little known outside his hometown of Concord, Massachusetts, where he was much admired for his passionate stance on social issues, his deep knowledge of natural history, and the originality of his lectures, essays, and books. He was also maligned as a crank and malingerer who never held a steady job and whose philosophy was but a pale imitation of Ralph Waldo Emerson's. Thoreau was a man of ideas who struggled all his life to create a path that would refuse compromise. All his activities--teaching, pencil-making, surveying, and, above all, writing--were grounded in his faith in a higher moral law that could be discovered and practiced through the unremitting discipline of living ever in the present moment. For Thoreau this belief meant living "in each season as it passes," fully attuned to the rhythms and phenomena of nature. His art, as...