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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Man is kind enough when he's not excited by religion, but once the holy holies have got a grip on him he's capable of almost anything. When a disciple from the wildcat religious asylum comes marching forth, get under the bed. It doesn't matter whether he's a Christian, Hindu, Jew, or Muslim. If he's made up his mind that you need reforming, he will do it with anything handy — an ax, eight hundred years of witch burning or, if necessary, he'll blow you up.
It is not the conscious changes made in their lives by men and women — a new job, a new town, a divorce — which really shape them, like the chapter headings in a biography, but a long, slow mutation of emotion, hidden, all-penetrative; something by which they may be so taken up that the practical outward changes of their lives in the world, noted with surprise, scandal, or envy by others, pass almost unnoticed by themselves.