If you asked fifty people if a story about monsters eating people's faces is science fiction, you'd receive fifty yesses. Yet, such a story would not be science fiction. It would be horror. Nothing against horror, except it isn’t science fiction.
Novels about magical spells aren’t science fiction either unless the story explains the technology of wizard magic. Stating that a wand contains a strand from a phoenix feather isn’t enough. Nothing against fantasy, but it isn’t science fiction either.
Science fiction is ordinary fiction with a scientific or technical theme about something that hasn’t yet happened, but could. The "but could" separates science fiction from fantasy and horror stories.
How does one write about something that hasn’t yet happened, but could? Could a benign virus mutate and kill half the people on Earth? One could. Could a vaccine for Alzheimer’s patients tested in apes result in Earth being taken over by apes? Well, maybe.
Science fiction is about events that could happen. Not goblins, vampires, or aliens from outer space eating people's faces.
Wait, what’s wrong with aliens eating people's faces? That could happen, right?
It could, but only if the aliens’ digestion systems required the same nine amino acids we need for digestion. Otherwise, their eating us would be like our eating wood or plastic. It would make them sick and they would go home in disgrace. All DNA on Earth, including that of people, animals, plants, and even bacteria, is composed of four chemical bases (adenine, guanine, cytosine, and thymine). What are the chances of life on other worlds having those same chemical components? If they don't, chances are they would not benefit by eating us.
Likewise, there is the problem of molecular chirality: the right/left-handedness of molecules. Would creatures from other worlds have the same molecular chirality as ours? And what about respiratory alkalosis? That is what happens when one inhales the incorrect percentage of carbon dioxide.
Then there is the problem with the sense of smell. We can smell things only when certain molecules in the air fit the shapes of specific receptors in our noses. What are the chances of extraterrestrials having smelling organs with receptors that match the smells on Earth?
I know someone who's been a mortician for thirty-years. He's taught himself not to smell certain odors. The problem with this impressive achievement is it has ruined his sense of taste for foods he would otherwise enjoy. This is because most odors (which also effect taste) are intertwined with other odors. Blocking the ability to smell certain nasty human decaying odors hinders his ability to smell other pleasant odors.
See how complex the physiology of reality is?
The list goes on. This may be why there are many more fantasy novels than science fiction novels. Too much heavy research.
What the story is really about
Good science fiction is introspective, meaning the story is never about what the antagonists do, but how the protagonists react to them internally and externally.
One of my favorite science fiction novels is Andromeda Strain, by Michael Crichton. It's about a small U.S. satellite that crashes near a little town in Arizona. The crash doesn’t kill anyone. But for some reason, shortly after the crash (nearly) everyone in the town is dead. What is causing the deaths? What a mystery! See, no monsters eating people’s faces are required.
Another of my favorite science fiction novels is 1984, by George Orwell. No extraterrestrial influence there. The Hunger Games series, by Suzanne Collins, is a story about what could happen. The same with the novel, Unwind, by Neal Shusterman, where teenagers can have their organs removed and donated to other people at the request of their parents. Ouch.
Why is “real” science fiction so rare?
I believe it's because it's difficult to write. It’s easier to tell about an adversary whisked away by magic words than to have the foe frozen by a micro-freeze device. Without some explanation (more than nothing) of how the micro-freeze device works, the story flirts toward fantasy. What explanation could be given for how a micro-freeze device works that doesn’t break a known rule of science? If you came up with a real explanation, you could build a micro-freeze yourself and patent it. You’d be rich. No fiction writing required.
So then, how does one go about writing good science fiction?
Find a hole
Here is your tip for today: Search for a gap in known science, a “hole” of knowledge that isn’t yet known. For example, you could discover through your research that to create a micro-freeze device, one would have to come up with a third kind of electron charge besides positive and negative. Then, you must research a yet unknown but plausible way to create that third charge.
Once you’ve done that, you have a scientific loophole through which you can weave your story. Voila! Pristine, shimmering, Grade-A science fiction that deserves international acclaim.
That is, if you also also do a hundred other things correctly.
I wrote the following post in my Facebook account. Yep, this pretty much sums it up: