The Greeks used to use the same stories, the same mythology,...

The Greeks used to use the same stories, the same mythology, time after time, different authors. There was no premium placed upon an original story, and indeed, Shakespeare likewise. A lot of people wrote plays about great kings. They didn't expect a brand-new story. It was what that new author made of the old story. It is probably the same now. We disguise it by inventing what seem to be new stories, but they're basically the same story anyway.