A friend of mine shelved his by publisher and number (back when there was a number distinct from ISBN.) I tried that for a while. It looked great in terms of spine title fonts and artwork - it was a pain finding anything.
In any case someday someone will write a space opera with urban vampires. That will show them!
I read an essay a few years ago (by John Scalzi, I think) in which he said SF differed from fantasy in that the devices/MacGuffins/etc. in the former had batteries (or some scientific power source), and in the latter they did not.
Right now I’m working on a story for a fantasy magazine, and I’m putting in several fantasy tropes to disguise the fact that essentially it’s a science fiction plot.
The history of this is actually less straightforward.
F&SF debuted in 1949 under the title The Magazine of Fantasy. It added Science Fiction to the title the next issue after it was pointed out that a) it ran both types of stories and b) buyers looked for science fiction magazines rather than fantasy magazines.
The Science Fiction Writers of America, started by Damon Knight in 1965, didn’t add Fantasy to its name until 1992. It was a very controversial move among the old guard (meaning Damon Knight) and any attempt to change the initials to the more logical SFFWA was quickly shot down.
Science fiction is the name for a publishing category. That category is quite recent. Scientific romance used to be the name but not a separate genre until Hugo Gernsback started Amazing Stories in 1926. He called it scientifiction, which lived on as a general name of the field until at least the 1940s. Science fiction slowly became the dominant identity in the 1930s but it was still a pulp magazine category only. Science fiction novels called by that name didn’t really appear until after WWII. The field boomed in the 1950s with several big publishers driving the smaller presses started by fans out of the market and really took off in the 1960s when just about every publisher had a science fiction paperback line. Fantasy as a recognized separate genre large enough to talk about didn’t emerge until the 1970s and by then science fiction was the umbrella name for everything.
In literary terms, science fiction is a subclass of fantasy. In academic terms, just about everything that is non-mimetic (everyday) fiction is part of science fiction including alternate history, utopias and dystopias, magical realism, paranormal romance, and superheroes. As with everything else, there are lumpers and splitters along with mainstream literary types who hate being classified as science fiction and try to find any possible way to avoid getting tagged as it.
Is Bradbury science fiction? Yes. No. Sometimes. Who cares? Choose any one and I’ll conclusively prove the case. 
So what stops him from going to his buddy and saying “hey, Joe, I think it would be REALLY NEAT if someone wrote a book about the hand-held-wish-fulfillment-device-with-universal-power-and-no-side-effects-or-monkeys-paw-style-clauses. Wouldn’t that be awesome? Why, if someone wrote that book, I might even help pay to get it published…”?
The McGuffin has to be well-known to the general reading public - so self-published thingies don’t generally do so hot, because not enough people know about them. Also, the libriomancers as a rule are trying like mad to keep people from knowing about this particular school of magic, to prevent that very situation. I have a feeling if a libriomancer made friends with a well-known creative writing type, that friendship would either be terminated, or very-well monitored.
I do seem to recall a mention being made at least a few entrepreneurial libriomancers who attempted to write fantasy/sf themselves, for the purpose of creating artifacts to use, and the general consensus seems to be that libriomancers are not creative enough, and don’t write well enough for their work to reach that “well-known” cut-off point.
What about publishing physically-extra-large editions of well known works?
C. S. Friedman’s The Madness Season. 
I’ve also noticed there’s been a growing philosophical overlap between the two over the decades. There’s been more and more science fiction that treats the sci-fi elements as black-box props that don’t need any explanation; it just replaces “it’s Magic!” with “it’s Super-Science” and gets on with what story elements the author cares about. On the other hand there’s more and more fantasy that treats magic as an alternate physics and tries to extrapolate the results like classic sci-fi.
Not to mention the stylistic overlap - for example, these days lots of magic-users fight with shields and energy bolts, just like starships in plenty of sci-fi.
Indeed. Mercedes Lackey goes into more “technical” detail about magical shields than Star Trek ever did about technological shields. One of her urban fantasy characters explicitly modeled his early shields on Star Trek shields, but later regarded such constructions as naive, and learned to build better ones.
Butcher’s Harry Dresden mostly uses more traditional magical elemental effects on the offense, but he relies on shields for defense, and one of his non-wizard associates got a handle on a key magical technique by putting it in terms of a science-fiction force field.
This is exactly what Knight was complaining about in the 1950s. I’ve been reading In Search of Wonder, his collection of criticism, so it’s fresh in my mind. You know that you’re in the past when Arthur C. Clarke is in a chapter on new writers.
Don’t people look at the cover, flip the book over and read the back, and maybe read a few random pages? “A story about a daring young sorcerer coming of age on an intergalactic space arc” should give you an idea of what you’re going to get.
Anyhoo, fantasy makes good TV shows and movies, but reading it bores me. Science Fiction makes great reading and TV shows and movies. I’ve read a few books with the two deliberately combined, and didn’t care for them much.
There’s nothing new about that - look at Zelazny’s Lord of Light from 1967. He makes no attempt whatsoever to anchor his “science” in anything real world. But then, Zelazny cared far more about Pablo Neruda than he did about Niels Bohr. Didn’t stop him from being one of the best science fiction writers ever.
I feel the OP. I really do.
Look, everything that you guys are saying is rational and reasonable and right, but man, I totally get where he’s coming from. Sometimes I just want to yell “Get yer stinkin’ dragons and spellbooks out of my nuclear armageddons!”
Is it, though? The quip upthread says it’s F or SF based on whether you’ve got a hovering dragon. So first we’ve got droids, and starships, and that crazy old wizard who these-aren’t-the-droids-you’re-looking-for like Mandrake the Magician, and the guy who’ll gesture-choke you if you insult his sorceror’s ways – and then, in the next installment, cue the wise old mentor who can levitate a whole X-Wing.
(And then cue the evil one who wills lightning out of his fingertips.)
Good questions! Hines answers them in the books!
Libriomancy’s magic, what makes it possible for the main character to reach into a book and grab something, is the combined belief and shared wonder of millions of people reading the book. That combined sharing of the book is what gives the book magic that he can touch. Further, it’s got to be the same book, or basically the same book, as everyone else has read. So, it can’t be the large type edition that maybe sees less than a tenth of the printing of the regular books. It can’t be the book club edition. It’s got to be the book that was popular and read by the most people.
Indeed, several plot points revolve around this and many other items, especially “locking” a book and I thought it was well done.
Good discussion! Thanks!
Well, consider the works of Douglas Adams: even leaving aside the DIRK GENTLY books, the HITCHHIKER’S GUIDE series of course starts off with starships and robots and a teleportation device, and before long our heroes – don’t know what to do next and so hold a séance to contact the spirit of a deceased ancestor. And cue more adventures in outer space, until for some reason – Thor the Viking god of thunder shows up.
Speaking of which,
What’s your beef with superheroes? Seems to me like Iron Man’s power armor could be straight-up science fiction, and Captain America is just a guy on steroids; they both hit harder than humanly possible, but neither of 'em can wiggle their fingers and turn someone into a toad.
What are your sci-fi classics? Mention H G Wells and an Invisible Man, I’ll point you to a superhero who likewise uses an invisibility serum; talk about Asimov’s Foundation series and I’ll show you another mutant with telepathic powers; refer to Dune and I’ll name several guys in tights who rely on a personal forcefield that only slow-moving attacks can overcome.
(I’d raid a list of the Hugo Awards to get more examples, but I see Watchmen is already on there. I also don’t know whether you’d consider the Six Million Dollar Man a superhero, but, c’mon, he totally is.)
Just an observation…
In both Bill Willingham’s Fables, and its spinoff, Jack of Fables, there comes a time when a villain must call in the genres of fiction. All are presented separately (“Western” is a cowboy, “War” is a WWII grunt, “Mystery” is a woman in a veil who says little, “Comedy” looks like Groucho Marx, complete with squirt-flower-in-the-lapel), except for “Science Fiction” and “Fantasy,” who are presented as twins.
SF, who looks like an astronaut, says things like, “I have a ray gun”; while Fantasy (who looks like Queen Titania of Faerie) says things like, “According to the Scroll of Thripenny, we will find our answer from the elves who inhabit the Hill of Scroyne.”
I find it interesting that in these works, Science Fiction and Fantasy are presented as twins, while no other genre is. Not that I’m a big fan of science fiction or fantasy, but I did find it interesting that the authors presented the two as twins.
Then why are you reading Fables? That’s about as fantasy as you’re gonna get. Archetypes of all kinds, mythical beasts, magic, etc.
Just to expand on my earlier post:
“Here’s an invisibility serum” - sci fi.
“Here’s an invisibility potion” - fantasy.
(I honestly don’t know which one “He’s a psychic detective” is.)
Virtually any science fiction story can be rewritten - with a few minor changes - as a fantasy story, and vice versa.