There is no such thing as a new idea. It is impossible. We simply take a lot of old ideas and put them into a sort of mental kaleidoscope. We give them a turn and they make new and curious combinations. We keep on turning and making new combinations indefinitely; but they are the same old pieces of colored glass that have been in use through all the ages.
Mark Twain, Mark Twain’s Own Autobiography: The Chapters From The North American Review

The key is to keep turning that kaleidoscope constantly…