I hope you guys don't mind my attempt at distinguishing the two genres with examples. Just a heads up though, I'm going to make this a very subjective take on what I believe qualifies science fiction and fantasy. For starters, I'm going to assert a few things about the genres and later provide reasoning. The setting alone is not a qualifier for the genres. Fantasy can be set in the future and science fiction can be set in the past. Correspondingly the presence of technology or magic does not force the book into one genre or the other. Mapping genres by trends is a good way to identify genres but a poor way to define genres. Finally as Cogito said, Fantasy and Science Fiction are both sub-genres of Speculative Fiction. Of course there are similarities. They are practically siblings in the fiction realm. Okay, I hope I can do this. Feel free to pick my attempt at logic to pieces. Oh, and if you want to take the short cut the last two paragraphs pretty much says it all. Whether is middle earth or alpha-centari, setting alone does not define the two genres even though it does help distinguish the trends. A fantasy book doesn't instantly become science fiction because the last line in the novel drops a reveal that the underground ruins the character had been exploring was actually new york city. Conversely, science fiction is not instantly a fantasy novel because a group of immortal forest people were discovered in a previously unmapped region with pointy ears and an unknown spoken language. (Actually, that reminds me of the horror genre for some reason. Damn you Lovecraft you fit in no box) Let me pull out my genre splitter. A Connecticut Yankee in King Arthur's Court. (Henceforth Yankee for short) Oh yeah. You read that right. We got some Mark Twain up in here. Well news flash I call it a genre splitter because it has elements of both science fiction and fantasy. For starters there is the time travel. Wait! Before you jump to any conclusions let me finish. The time travel premise in a Yankee is actually a fantasy element, a completely unexplained impossible event. Then, there are the speculative elements of the book what would happen to a modern man stuck in a fictional past? In Yankee, the speculative element is Science Fiction. The modern man takes advantage of the known phenomena called a solar eclipse. He engineers machines of war, constructs modern tools, and even makes a bomb. I drag speculative element into the science fiction category, the book shows and makes an attempt at explaining the effects of modern technology in a historically based culture. But don't forget the last battle. Even the wizard pulls out some magic of his own. As far as the narrator is concerned it is real, honest-to-god, science-be-damned, magic. So the setting, with knights and wizards and a realm where magic is possible makes it mostly fantasy setting, but let's not forget the setting includes the original time frame of the book that's part of the setting too. There is the reveal at the end too. Did he actually travel back in time? Was it all just a dream from hitting his head? Whatever, I already said stuff like that doesn't matter. Since I got tired I'll just wrap it up and reveal that my subjective definition is really really subjective, and easily displayed visually. It works well for me. In essence Yankee is a science fiction novel despite its majority of fantasy elements. In the genre of speculative fiction the quality of speculation is the category of the first order that determines its sub-genres. The second order falls to setting and the third order is tropes and trends like vampires and chosen boys of destiny, or drug riddled dystopian slums and laser guns. I do the same for sub-sub-genres too. Cyberpunk and Steampunk. Oh yeah you can bet that I flame about the difference between fantasy steam punk and science fiction steam punk too. (J/K) Honestly, this method works for me because I read for the speculative elements in fiction. Its my favorite part above all others. Human behavior, robot behavior, cultural dynamics of werewolves an humans, whether science-y speculation or fantasy ends up as the most prominent is how I determine which the genre the book goes into for me. Other people read books for the rich setting diverse environments of the world building masters, Herbert, Lovecraft and Tolkien. I think that readers engaged by setting tend to define genres by the setting. To do a little self-parody, just for fun. Fantasy fans: "I define my genres by the setting of the novel" Sci-Fi fans: "I define my genres by the qualitative value of the speculative fiction" Publishers: "I decide the genres based on a the single sentence of premise I read." And that's where baby's come from... -I -I mean, and that's where genre discrepancy comes from.
Well I know the two have their different sub-genres which make it a little confusing. Depending on who your talking to, science fiction can have 4 to 14 subgenres. But I think where the boundaries blur between fantasy and science fiction is maybe space opera. Science itself takes a backseat in space opera as it focuses on "good guys vs bad guys" pretty much. Star Trek may be Soft Science fiction I think but they still try to explain everything in technobabble and you can really see the difference in dialogue. "We need to keep our phasers on a rotating modulation so the borg do not adapt" "Blast them!" "Dilithium crystals are callabrated. Warp containment field is at optimal integrity. Coolant system is running at nominal temperatures. Power systems are at 100%. Now engaging warp drive for Warp 1.0" "Punch it Chewie!"
