Allow me to provide a guideline to think through when deciding what to include:
I like these quotes as a jumping off point
“Science Fiction is something that could happen – but usually you wouldn’t want it to. Fantasy is something that couldn’t happen, though often you only wish that it could.”
– Arthur C Clarke
“A handy short definition of almost all science fiction might read: realistic speculation about possible future events, based solidly on adequate knowledge of the real world, past and present, and on a thorough understanding of the nature and significance of the scientific method." - Robert A. Heinlein
If something is Science Fiction or Fantasy (or neither) depends on two things, from my perspective:
1. What narrative tropes is it fulfilling?
2. If there is futuristic technology (or aliens or space travel), is there some explanation for it that is, for the most part, grounded in science and reality (or realistic speculation of something that could be possible).
Let’s take a few of the case points people are discussing:
1. Star Wars, while including futuristic technology, rarely attempts to provide rational logic for why these absurd things happen. Things occur because of “The Force” or because they can, and while there may be some in-universe rules it abides by, it certainly does not even attempt to abide by the rules of the universe we live in. Case in point it does not pass the bar of Heinlein’s definition, or the second point that I listed.
2. Star Wars, narratively is not attempting to speculate on anything that could be. Classic Star Wars actually follows classic fantasy tropes to the t (A Farmboy meets a wise “wizard” who sends him on a heroic journey to rescue a princess from the castle of a purely evil “black knight” type of character. Space swords and magic in it and all). Maybe some extended universe stuff goes closer to to the sci-fi realm but the movies clearly don’t. It’s a fantasy story set in space (think how Steampunk is fantasy as it’s a fantasy story with the inclusion of industrial revolution style tech. Star Wars is fantasy with futuristic tech)
This is a very broad one to cover, and some comic book stories could be argued as truly being sci-fi, which is a branch of speculative fiction. I’m thinking of Watchmen in particular is maybe the closest one of the big name brand superheroes gets to being truly sci-fi
I’ll just pick a few to get the point that none of the ones that I think people are considering really count.
In general the superhero genre is its own genre and not sci-fi. Excluding the point about technology, the classic superhero narrative tropes are very distinct from speculative fiction, they’re fantastical in nature to the point I’d rather just call them contemporary fantasy stories (kind of like Harry Potter).
1. There’s rarely any grounding in science. Superman has these magical powers simply because he does, Batman and Iron Man can create ridiculous tech simply because it’s cool, etc. Even in cases of attempts to explain how the super powers are possible they’re very superficial in layers and usually about as absurd in real world grounding as no explanation at all. For example, Spider-Man gets super powers because he gets bit by a radioactive spider, it’s silly logic that has no basis in reality, but we give it narrative passes because the genre is not based in reality.
2. Even in cases of the “realistic” superheroes, like Nolan’s Batman, it doesn’t satisfy the “speculative fiction” element that is essential for science fiction. Batman boils down to a rich billionaire fighting crime and corruption in his city, sometimes coming up with cool tech devices to do so. Stuff like the MCU, provides the absurdistic rationales (that work because they’re fantasy movies) and thematically aren’t actually focused on speculative fiction elements and focuses a bit more on the classic “Good vs Evil” fantasy tropes. Even with something like Black Panther, the advanced technology is usually handwaved away by being possible because of some magical material called Vibranium.
I think there are cases of comic book movies being Sci-Fi. But the only modern big brand one that I think comes close to fitting the bill is Watchmen
Gravity and The Martian
Now that I said that, I do think something like Gravity or The Martian are clearly in the realms of science fiction.
1. Both of these films are fiction, not based on real events, so that’s one reason they pass the bar but Apollo 11 or First Man do not.
2. They’re grounded in science, even if some aspects of the film don’t exactly line up with reality, for the most part they’re grounded in the universe we live in (or a speculation of what a future iteration of our universe could look like). Think, stuff like the MCU or Star Wars are not realistically grounded in our universe or a speculative future version of it.
3. They’re both speculative stories to certain extents. Gravity, while using contemporary technology, is a speculative account about a disastrous event that could potentially occur . It has themes that are dealing with human relation to technology (the disaster is not a natural one, it’s based on a technological failure). It would clearly fit the bill of Heinlein’s definition, and the Martian would as well.
I think the reason some people don’t include something like Gravity as sci-fi is because they’re including fantasy stories like the MCU or Star Wars in their definitions.
Caveat: I want to add that the way I’m using the phrase “speculative fiction” here probably isn’t the most accurate as fantasy and horror stories are often included under it (but for different reasons). I’m using the phrase as speculating about potentially ‘realistic‘ future events or technology. Ie: What would it look like if this possible future scenario occurred (usually relating to technology grounded in science and the rules of the universe we are in).
Maybe not the best way to use the phrase speculative fiction but in terms of my post I think it’s adequate in explaining why certain things are and are not sci-fi.