In science fiction, people often confuse narrative realism with "hard," or scientifically-accurate, storytelling. But in fact, hard science fiction is one of the most unrealistic subgenres of SF.
When you're talking about storytelling, the term "realism" has a fairly specific definition that comes from the world of literature. In the late-nineteenth century, a new wave of novelists like Gustav Flaubert (author of Madame Bovary), George Eliot (Middlemarch) and Mark Twain (Huckleberry Finn) began to write stories about ordinary people's everyday problems, in an effort to capture "real" human experience. They were in some ways revolting against the romantic tradition in literature, which was full of larger-than-life characters and stories that were often idealistic rather than realistic.
Over the decades, realism crept out of literature and into other forms, like painting and movie-making. In the early 1940s, popular American film Sullivan's Travels made fun of realism, showing its pampered Hollywood director trying to discover how "the common man" lived in order to make a "realistic movie." What he discovers, after accidentally being thrown in jail and forced to work a chain gang, is that ordinary people desperately crave escapist entertainment, rather than weighty stories about their own crappy lives.
The point is, realism in fiction and film has generally been an effort to represent the experiences of ordinary people - whether they're poor people in jail, like in Sullivan's Travels, or bored middle-class housewives, like Madame Bovary. Realism is about accurately representing the social world in all its complexity, rather than just telling the stories of rebel heroes and extraordinary leaders.
You'd think that realism would have a lot in common with hard science fiction, since both emphasize accuracy. In fact people who love hard SF often look down their noses at social science fiction as being "unrealistic." And yet, viewed through the lens of fictional realism, hard SF fails in every way.
A few writers, like Greg Egan, Octavia Butler and Ken MacLeod, make an effort to include ordinary people in their hard SF tales. And the recent movie Moon was an effort to tell a hard SF tale of a regular guy (though many people have grumbled about the inaccurate Moon base).
But for the most part, hard SF novels lavish verisimilitude on the technologies they describe but turn their characters into unrealistic megabeings with superpowers. Even Iain M. Banks is guilty of this with his transhuman spies and agents, though his depictions of future societies are generally nuanced. Many of the luminaries of hard SF, from Isaac Asimov to Charles Stross, do a terrific job of describing everyday technologies of the future (or alternate realities), but fall down when it comes to everyday life.
Meanwhile authors like Carol Emschwiller, Ursula Le Guin, and Jim Munroe write strongly realist SF, possibly because they spend more time building up social worlds than they do focusing on technologies. William Gibson is a terrific realist as well, though I think his depiction of technology could be considered "hard" in some cases. And most movies and television series, when they strive for realism at all, tend to embody the literary definition of realism rather than the scientific accuracy of hard SF. This is certainly the case in Star Trek, where we encounter a lot of ordinary people planetside (even the villain of the JJ Abrams Star Trek movie is basically a regular guy gone insane) - but the technology is usually powered by handwavium, if you know what I mean.
It seems to me that realism and hard SF should be natural allies. Maybe it's time that we start demanding SF realism to go along with scientific accuracy. After all, the future is going to be full of regular people leading ordinary lives. Heroes and mutants are fun, but I'd like to know what's going on outside the flagships and rebel headquarters and elite corps once in a while too.
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