Henry David Thoreau (born David Henry Thoreau; July 12, 1817 - May 6, 1862) was an American author, naturalist, transcendentalist, tax resister, development critic, sage writer and philosopher. He is best known for his book Walden, a reflection upon simple living in natural surroundings, and his essay, Civil Disobedience, an argument for individual resistance to civil government in moral opposition to an unjust state.