It has long been unfashionable to think of fiction as having a purpose. Still, what is "fashionable" has absolutely no value for anyone trying to understand anything. (All the more so as actually trying to understand things is also unfashionable.)
Looking back over science fiction in the past year, it has seemed undeniable that from H.G. Wells to John Campbell to Horace Gold, science fiction's prime movers regarded their genre as having a special purpose, apart from other kinds of fiction--and that the genre did realize that purpose. Science fiction helped us discuss science, technology, the future. Specifically it helped accustom us to talking about these subjects, and helped develop and popularize the tools for doing so--like the thought-experiments we call "extrapolation."
Science fiction also helped bring the fantastic back into literature more generally.
Yet, having accomplished all that, science fiction also became less special, less important. Pop science has come a long way since Wells' day. So too futurology. Someone who wants to publicly speculate about what some new technology will mean, for example, does not have to write up his ideas in fictional form. He can just as easily use those old science fiction tools in a piece of nonfiction--which may be all the more effective at its job for not having to work as a story, not having to bother with plot, characters and the like (as Wells did not in Anticipations, and decreasingly did even in his novels). And those who would go beyond mundane reality in telling their stories need not dress up the fantastic in scientific jargon (the way Wells felt he had to when he began writing his scientific romances). Indeed, today fantasy seems to have trumped science fiction, with the popular market and with the critics alike.
The old mission having run its course, science fiction writers, by the 1960s, increasingly prioritized other things--things which diminished their ability to deal with science fiction's traditional concerns. The emphasis of many on Modernist and postmodernist subjectivity and irrationality in their choice of content and style were absolutely at odds with the "science" in science fiction, and edged it out over time, as science fiction increasingly abandoned its old interests to the end of becoming regular old fiction which simply happened to have science fiction's trappings.
Indeed, even getting away from the highbrow, artier end of the genre, one suspects that many of the old formulas which retain their popularity are having an effect opposite to what science fiction once did. Rather than helping us think about science, technology, and the future, the genre trades in ideas inhibiting this. The Frankenstein complex (which had even Asimov's I, Robot present us with robot rebellion). The Edisonade (epitomized by Iron Man Tony Stark). Science fiction where the "science" is really pseudoscience (as Carl Sagan complained about The X-Files). There are plenty of reasons for all this, like the ease of fitting such material into a superficially character-centered dramatic narrative, the appeal of the sensational, and so forth. But really these ideas are lingering on past their time and cluttering and confusing things.
One way of looking at this may be to think that science fiction ran its course and, over the last half century, became increasingly decadent--reaching the condition that Paul Kincaid famously criticized a few years ago, recycling old ideas, more or less nostalgically, or playing the game ironically, or even being just fantasy (or even mundane) fiction passed off as sf. Certainly I have tended to that view in many of my writings on the subject. However, one might also imagine that the stage has been set for "science fiction 2.0"--for science fiction to set aside its old tasks (and old devices), and take on some new task, using speculative science to look at the world in a new way (or perhaps even an old way we've simply forgotten). In today's cultural climate it is hard to picture anyone actually doing anything like that--writers and editors and critics too leery of such seriousness. Yet, it seems to me that that possibility does exist.
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