Most agree that a useful definition of creative work is that it includes a combination of novelty and value. Creativity requires novelty because tried-and-true solutions are not creative, even if they are ingenious and useful. And creative works must be valuable (useful or illuminating to at least some members of the population) because a work that is merely odd is not creative. This two-pronged definition of creativity also provides an explanation of why the creative can lie close to the insane (unusual but valueless behavior).