Meet Genre Doe: Definitions of SF/F

Meet Genre Doe: Definitions of SF/F

Once, before I gave up arguing with anyone, I was arguing with someone and I wrote, “Science fiction is just a form of fantasy with stricter (but slightly inconsistent) rules. Fantasy fiction takes place in a world which does not exist, operating on principles chosen by the author; science fiction takes place in a world which doesn’t exist but might, operating on the principles of science as we understand it (with some cheating allowed in the form of time travel, FTL drives, Amazing Mental Powers etc).”

They weren’t impressed, as far as I could tell. Anyway, now I’d alter those formulations a little:

Fantasy is a mode of storytelling where all or part of a story takes place in a world which permits events that are impossible.

Science fiction is a genre of fantasy in which impossible events require some sort of scientific account or rationalization.

Science fantasy is a genre of fantasy that uses elements from science and technology but in which some impossible events are explicitly not given an adequate scientific account or rationalization.

I’m using impossible in a broad yet specific sense here. I mean “impossible now.” It would be possible (however unlikely) for me to go out and rob a series of banks, buy an airline ticket to Rome and have some decent gelato for dessert tomorrow night. (In practical terms, it’s just not going to happen: my own decisions abrogate this version of the future. So any daydream about it is a fantasy to the extent that my own decisions put it out of realization.)

It is not possible, in our current state of scientific knowledge and technological ability, for me to simply teleport myself to Rome and have gelato tonight. Maybe it will be possible someday, but at the moment it’s not. So, in a story, this would fall within the range of fantasy, and whether it’s sf or a different genre of fantasy depends on the account given of the teleportation-method.

But suppose someone believed that teleportation (as a psychic power, or a top secret government project, or whatever) was possible now? Then for them, the story’s not fantasy or science fiction. If the storyteller and the audience don’t agree on the shape of reality (as is not uncommon), the ability for a story to be fantasy (or to be effectively told at all) may be compromised.

In general, it seems to me, we should look at the writer’s intentions (an unfashionable theoretical position these days). A competent writer will signal genre intent. (And may give conflicting signals: that’s a fair variation on the storytelling game, it seems to me.) But the reader’s experience counts, too, and much that was intended in, say, the 1930s as science fiction is read as science fantasy today. This may look like a contradiction, but it’s really not. All genre categories overlap with others and exclusive definitions probably aren’t possible (or desirable).

Anyway, that’s what I’d say nowadays if I said stuff like that nowadays.

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M Harold Page

I’m afraid I think it’s more to do with the props. For example,
Rockets and lasers => SF.
Dragons and swords => Fantasy.
Rockets and Swords => “Swords and Planets”
Dragons and lasers > SF.

Erik Mona

How about this?

What about “science fiction” from the 1920s or 1930s in which then-plausible science is posited, but which later revelations have invalidated.

Do stories magically become “fantasy” then this happens?


I recently had a discussion on another blog dealing with the definition of SF in which the blogger claimed (as you do) that SF deals with the possible (with some wiggle room) and fantasy with the impossible. Specifically, he claimed science fiction cannot involve the supernatural.

I pointed out that this definition, defining the supernatural as impossible, makes science fiction out to be in opposition to religion—by his definition, religion is false (there is no God, no angels, no other supernatural entities).

I happen to not believe in the supernatural myself but I still don’t define SF in such a way that all supernaturalist religions MUST be mistaken for something to be SF.

CS Lewis’s OUT OF THE SILENT PLANET, for example, I would consider science fiction. He considered it fantasy (or probably fantasy, based on my description of it, since he hadn’t read it) because it depicts christianity as being true and angels being real. This seems completely wrong to me. The AUTHOR must believe the thing is impossible for the story to be fantasy, in my opinion. A man who believes in vampires and writes a story about vampires isn’t writing a fantasy novel.

I would revise the definition of fantasy to be stories the writer and intended audience understand to be impossible.

And the reverse for SF. So, by my definition, there can be such a thing as christian SF like Lewis’ Space Trilogy in which the supernatural turns out to be real (the same, of course, goes for other religions—Buddhist SF, or whatever).

What are your thoughts on religion and the definition of SF?


I should have read your definition more carefully, forget the “as you do” in the first sentence above. Similar definition but not the same.


You point is well-taken about belief, but problems arise when the author and the audience differ in their beliefs….

Yes, that’s why I say intended audience (one the author expects to understand his point of view).

Are the fantastic parts of the Odyssey science fiction (by Homer’s standards) or fantasy?

Neither by the definitions I would employ. For something to be SF, by my definition, it must include scientific speculation. Homer likely had little or no concept of science so he’d be hard put, to say the least, to come up with a science fiction story.

Another example would be the LEFT BEHIND series. Its not fantasy (because its authors believe it to be basically what’s going to happen in the future—in general outline if not in detail).

Despite very minor science fictional elements (like improvements in agriculture), its not science fiction, in my opinion, because the element of scientific speculation is too minor (much the same goes for most James Bond stories despite the high tech gadgets).

So I think genre identity, like most kinds of meaning, is negotiated between the author and the audience; neither has absolute control

Personally, I give authorial intent by far the greatest weight.

To me Greek mythology is utterly fantastical. But I still think it should be categorized as religious literature and myth as distinct from fantasy.

This approach, anyway, is the one that seems most useful—which is all that I expect of a definition.


The “Left Behind” books might fall in that category.

Of course there are lots of ways any book can be categorized (the same book can be reasonably labelled science fiction and horror, for example).

In regard to the LEFT BEHIND series, the label that seems most useful to me is christian apocalyptic fiction. That’s a label that really tells you what kind of book you’re going to be reading.

“Tomorrow fiction”, while it might be technically accurate, doesn’t do much to tell me what sort of book I’m picking up when applied to Left Behind.

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