One problem with Star Wars, science fiction writers say, is that it is not, ultimately, concerned with science, but rather with a timeless vision of good and evil. Mr. Lucas has said that his story, especially the journeys of his central characters from innocence through trials by fire to wisdom and acceptance, were rooted in Joseph Campbell's comparative studies of world mythologies, and especially in his popular book, "The Hero With a Thousand Faces."
What Mr. Lucas may have seen as eternal, however, science fiction writers have tended to see as antique.
"It started out 30 years behind," said Ursula K. Le Guin. "Science fiction was doing all sorts of thinking and literary experiments on a totally different plane. 'Star Wars' was just sort of fun."
"It takes these very stock metaphors of empire in space and monstrously bad people and wonderfully good people and plays out a bunch of stock operatic themes in space suits," she said. "You can do it with cowboy suits as well."
Science fiction, on the other hand, "is a set of metaphors," Ms. Le Guin said. "It's useful for thinking about certain things in our lives - if society was different in some way, what would it be like?"