单选题
There is no end to the magic within this circle of the world we live in. The greatest magicians today are
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the physicists and chemists, the mathematicians and astronomers: the wise men seeking the answers
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the riddles of earth and universe. But
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of them can tell us how to walk
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a floor, "by the law of gravitation"
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the readiest answer
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that.
Gravitation is
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the most familiar thing in all the world, and we were all brought
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on the story of Newton and his apple and the law of gravitation.
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physicists have begun to say that gravitation may be
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an illusion. If it is an illusion,
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it is pure magic that
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our feet on the ground and our furniture
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floating off into space. And who cares,
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the magic works and the illusion is
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? It is all a matter of vocabulary
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, for no two scholars have ever agreed
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a definition of magic; but there is no denying
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every time man has finally understood and explained a
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he has ceased to call it magic and called it
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instead.