From none other than Carl Sagan, May 1978:
The greatest human significance of science fiction may be as thought experiments, as attempts to minimize future shock, as contemplations of alternative destinies. This is part of the reason that science fiction has so wide an appeal among young people: It is they who will live in the future. No society on earth today is well adapted to the earth of 100 or 200 years from now (if we are wise enough or lucky enough to survive that long). We desperately need an exploration of alternative futures, both experimental and conceptual. The stories of Eric Frank Russell were very much to this point. We were able to see conceivable alternative economic systems, or the great efficiency of a unified passive resistance to an occupying power. In modern science fiction can also be found useful suggestions for making a revolution in an oppressive computerized society, as in Heinlein's “The Moon is a Harsh Mistress.” Such ideas, when encountered young, can influence adult behavior.
Emphasis mine. SF, and fantasy, are at core about imagining how things can be different, why they might be different, and how we might all fare under those circumstances. How plausible such things might be isn't really what matters; what matters is the act of imagining, the process. The hazard here is not letting all this take place in a vacuum uninformed by the realities of human psychology.
Much of the utopianism in SF is like this: it imagines a conflictless future, and the path it paves to get there is either one of blood atop blood (either conveniently kept out of frame, or lingered on because that's what the author and the prospective audience like), or one by way of assumptions about human behavior that aren't in evidence. It was the dystopians and the cyberpunks and the anti-John W. Campbell-ites, the folks who saw technology as not good and not evil but not neutral, either, who had a better sense of how all this might play out. They offered us not "wouldn't it be cool if?" but "if this goes on ... ". Not enough of us were listening, I guess. To that end, there's been a couple of efforts to turn away from "negative" SF and create "positive" versions of it — e.g., Hieroglyph, or the recently announced Better Worlds.
Thing is, I keep thinking "negative" (doomsaying, cynical) and "positive" (visionary, idealistic) are not the polarities at work here. The real division seems to be between work that flatters our prejudices, whether they are negative or positive, and work that is genuinely skeptical and inquisitive about our place in the universe — that does not say only "wouldn't it be cool if?" or "if this goes on", but is informed by greater dichotomies than only those things.
Very few SF or fantasy authors work like this — Lem, Dick, Tiptree, Sturgeon, Delaney, Simak (at his best). They don't just say, we can do this, or, we can save ourselves. They say, we can do this, we can save ourselves, but it will always cost us something, it will always leave us in a very different place, and this is what that place will feel like. Maybe this is what it means to truly imagine the future — what the future will mean to you and me, those who live in it and at the bottom of it, and not only what it means to people who Save The World or Build The Future. (My own work suffers from this, I admit.)
Still, I go back to Sagan's conceit a lot. The best way to deal with the future, in whatever form it comes in, is to try and imagine as many possible incarnations of it, with as many possible flavors and overtones. Then at least we can't say we weren't warned.
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