Mark Twain's amazing insight into human nature

Tom said to himself that it was not such a hollow world after all. He had discovered the great law of human action, without knowing it -- namely that in order to make a man or a boy covet a thing, it is only necessary to make the thing difficult to attain. If he had been a great and wise philosopher, like the writer of this book, he would now have comprehended that Work consists of whatever a body is obliged to do, and that Play consists of whatever a body is not obliged to do.

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