Samuel Langhorne Clemens (November 30, 1835 – April 21, 1910), known by his pen name Mark Twain, was an American writer, humorist, entrepreneur, publisher, and lecturer. He was lauded as the "greatest humorist [the United States] has produced", and William Faulkner called him "the father of American literature". His novels include The Adventures of Tom Sawyer (1876) and its sequel, the Adventures of Huckleberry Finn (1884), the latter often called "The Great American Novel".
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It has become a common feeling, I believe, as we have watched our heroes falling over the years, that our own small stone of activism, which might not seem to measure up to the rugged boulders of heroism we have so admired, is a paltry offering toward the building of an edifice of hope. Many who believe this choose to withhold their offerings out of shame. This is the tragedy of the world. For we can do nothing substantial toward changing our course on the planet, a destructive one, without rousing ourselves, individual by individual, and bringing our small, imperfect stones to the pile.