Metaphors, What for?

                     In his piece about metaphors, John R. Searle comes forth with his disagreement on metaphors. Personally I would have to agree with him the use of metaphors is not always necessary. I do not mind them however, why make them extremely difficult to understand like, "Sally is a prime number between 17 and 23." What good can come out of that metaphor? If one does not have a certain intellectual level then it is foreign language. Why can't society stick to similes?                    

                    Yet, I do not close myself to metaphors, even if I find them useless at times, I do have to recognize that metaphors embellish a piece of literature. In spite of this, literature would be much easier to understand without having to figure out all the metaphors and what they mean.