Every improvement that is put upon the real estate is the result of an idea in somebody's head. The skyscraper is another idea; the railroad is another; the telephone and all those things are merely symbols which represent ideas. An andiron, a wash-tub, is the result of an idea that did not exist before.
Mark TwainIndecency, vulgarity, obscenity - these are strictly confined to man; he invented them. Among the higher animals there is no trace of them. They hide nothing. They are not ashamed.
Mark TwainIt is our nature to conform; it is a force which not many can successfully resist. What is its seat? The inborn requirement of self-approval.
Mark Twain