It has always seemed to me that if there were such a thing as "mainstream," science fiction should belong, at least marginally, to it, for everyone who writes, whatever he may write, does so within the parameters of a literary tradition that has evolved, developed, and changed through the years. And the effort to disassociate fantasy (which is pretty much an undefinable term) and science fiction (which is perhaps as much so) arises from the intricate business of arguing how many angels can dance on the head of a pin. I don't think that we should attempt to distinguish between the two, and that the writer, especially, should disregard any artificial line that exists between them. The best stories, it seems to me, are fantasies, whether they be based on solid scientific extrapolation, or on engineering concepts carried to an ultimate point, or on something else.
I have to say, "or on something else" is a bit weaselly, isn't it?
I agree with Simak, except maybe for the statement about the "best" stories being fantasies. I'm sure I've said something like that myself, but it's an opinion I've now abandoned. There are other people whose tastes don't run to fantasy, and those tastes are as legitimate as mine. I've decided I don't care for literary elitism, whether it comes from sf-fans or non-fans. Fantasy and science fiction, I am coming to believe, are merely forms of artistic expression, neither more nor less legitimate than other forms. They are useful for expressing certain things and less useful for expressing others, for which we have other art forms.
It is probably this relaxed opinion that leads me to be so opposed to the uptight attacks on fantasy often heard today from certain Christian circles, where fantasy is either opposed in its entirety or, more commonly, subjected to a rigorous set of arbitrary and self-contradictory rules purposely designed so that no authors may pass muster unless named Lewis or Tolkien.
To the people who make such rules, I say this. In this same volume, SF: The Other Side of Realism, is an essay by Lionel Stevenson, "Science Fiction as Romance." He makes mention of W. D. Howells, who insisted "that all fiction was immoral unless it was confined to the everyday behavior and language of ordinary people" (pp. 98-99). Howells's rule is strict, but it can be consistently followed. The rules of today's Christian fantasy fan, who wants to have his cake and eat it too, cannot be consistently followed. It is no good to approve Tolkien's elves and wizards in one breath and condemn Rowling's wizards and witches in the next. Either give up fantasy entirely like Howells or else accept all of fantasy's tropes. The real moral concern in a work of fantasy is the same as in any other story: it is the underpinning philosophy that the writer conveys, not the magic and other devices he uses to convey it.