Answer: The author of the introduction is probably trying to show why Oedipus the Kings is a work of literature worth reading, and what is Sophocles’ merit in writing that play.
There is a gap of almost twenty centuries between us and Sophocles, so the introduction to the book is trying to show you why its themes are still valuable and worth reading today. It also highlights the difference between the fable of Oedipus and the way Sophocles turns it into a work of art.
