Henry David Thoreau (see name pronunciation; July 12, 1817 – May 6, 1862) was an American essayist, poet, philosopher, abolitionist, naturalist, tax resister, development critic, surveyor, and historian. A leading transcendentalist, Thoreau is best known for his book Walden, a reflection upon simple living in natural surroundings, and his essay "Civil Disobedience" (originally published as "Resistance to Civil Government"), an argument for disobedience to an unjust state.
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A man's ignorance sometimes is not only useful, but beautiful — while his knowledge, so called, is oftentimes worse than useless, besides being ugly. Which is the best man to deal with — he who knows nothing about a subject, and, what is extremely rare, knows that he knows nothing, or he who really knows something about it, but thinks that he knows all?