«It takes a thousand men to invent a telegraph, or a steam engine, or a phonograph, or a telephone or any other important thing — and the last man gets the credit and we forget the others. He added his little mite — that is all he did. These object lessons should teach us that ninety-nine parts of all things that proceed from the intellect are plagiarisms, pure and simple; and the lesson ought to make us modest. But nothing can do that.»

Mark Twain in a letter to Hellen Keller
http://www.brainpickings.org/index.php/2012/05/10/mark-twain-helen-keller-plagiarism-originality/