That’s a good question. Probably not one that has an answer you can get a decent majority of SF fans to agree on, unfortunately.
My take on it is that you’re not going to have much luck defining genres in terms of static attributes; they’re more like loosely bound clusters in the space of themes, tropes, and influences. Star Trek’s clearly inheriting from older SF-genre stories—Forbidden Planet, certain Larry Niven novels, all sorts of stuff if you break it down to individual episodes—so I’m comfortable calling it that.
Space opera, meanwhile, points to a thread that’s interwoven with SF but not encompassed by it. It influences a lot of media that also use SF themes and which I’d feel comfortable filing under both categories: the Culture books, Battlestar Galactica, and so forth. But it also influences some that don’t; Star Wars draws from planetary romance, heroic fantasy, and samurai movies, but not much pure SF, so I might call it space opera but not science fiction. Or I might not, depending on how wide a net I want to cast with the term.
That’s a good question. Probably not one that has an answer you can get a decent majority of SF fans to agree on, unfortunately.
My take on it is that you’re not going to have much luck defining genres in terms of static attributes; they’re more like loosely bound clusters in the space of themes, tropes, and influences. Star Trek’s clearly inheriting from older SF-genre stories—Forbidden Planet, certain Larry Niven novels, all sorts of stuff if you break it down to individual episodes—so I’m comfortable calling it that.
Space opera, meanwhile, points to a thread that’s interwoven with SF but not encompassed by it. It influences a lot of media that also use SF themes and which I’d feel comfortable filing under both categories: the Culture books, Battlestar Galactica, and so forth. But it also influences some that don’t; Star Wars draws from planetary romance, heroic fantasy, and samurai movies, but not much pure SF, so I might call it space opera but not science fiction. Or I might not, depending on how wide a net I want to cast with the term.