A major problem in fiction is getting people to believe your bull. The steepest hills are in those genres which are speculative and fantastical. These hills are steep, because people don't believe just any bull story. Yes, on the one hand, people want bull. If you laid down your hard earned money to watch a movie about vampires, then you're paid for some bull. But, on the other hand, people are finicky. They want bull that doesn't smell. They want to believe.
Two Main Master Strategies are those of Fidelity and Coherence.
Fidelity - making the story "ring true" in terms of other narratives people have heard about the word. There are religious narratives, scientific narratives, folk narratives, etc. Which narrative is ascendant depends on the age. Today, the scientific narrative is king and it is basically the paradigm of our age (if you can prove it scientifically, that's the gold standard). Other narratives, however, still have some saying power.
Appeal to Paradigm
Lie to me, but make me believe you.
Two Main Master Strategies are those of Fidelity and Coherence.
Fidelity - making the story "ring true" in terms of other narratives people have heard about the word. There are religious narratives, scientific narratives, folk narratives, etc. Which narrative is ascendant depends on the age. Today, the scientific narrative is king and it is basically the paradigm of our age (if you can prove it scientifically, that's the gold standard). Other narratives, however, still have some saying power.
Appeal to Paradigm
EX: "Science"Science Fiction: Projection to the FutureEX: Warp Drive allows go-fast in space. It's all very technical, but trust Geordi. He doesn't wear that funny visor for nothing.Fantasy: Reduction to the Mundane
EX: Troll Hunter - Trolls explode and turn to stone in sunlight, because they cannot process Vitamin D.
The problem for the trolls is that they are not able to convert vitamin D-From the sunlight, as we can, to lime or calcium. When exposed to sunlight the body overreacts completely. The stomach swells up. Gas is forced out of the digestive system and blood vessels with enormous pressure. And then they burst?
-Yes.
-But some trolls calcify?
-Yes, the older trolls calcify. The blood vessels are too narrow, such expansion will occur in the bones.
Horror: Reduction to the MundaneEX: Blade - Vampirism turns out to be a mere blood disease. Mundane explanation is used to get us to buy-in, which makes it easier to swallow the non-mundane pill which comes in the 3rd act. But there is also a literal blood-god called "Malagra" which can be summoned with the ritual sacrifice of a day walker. This is a sort of cashing in of the store credit earned with the sciency nonsense at the beginning of the film (Well, kids, if you're still with us, then you're ready to believe in blood gods). Blade is pretty close to being a paridigm-fusion in which two paradigms are used as self-reinforcement to sell the world of the fiction.
Paradigm Fusion (mutual bull-muckery)
EX: Religio-Scientific (Horseshoe/Boomerang Pattern)
Coherence - If we're not selling our bull with an associative/reductive appeal to some paradigm (showing people that our BS kind of fits there if we stretch things a bit), we can also appeal to the internal logic of our story. That is, establish your rules and play by them. These rules include our "laws of physics" for our realm, but also our style. Is the film realistic, surreal, whimsical, grounded, allegorical, etc. What is the style/tone of the story. Playing by your own rules is not only expected by the audience, but also does something to establish the world itself (kind of speaking itself into existence).EX: Event Horizon (space ship opens portal to Hell via a singularity - the "gravity drive"). Event Horizon goes to the trouble to "scientifically" explain how to use a blackhole to cheat relativity theory, but also asserts a deeper background reality hiding behind the mundane world which invokes the older paradigm of religion.
EX: Pulse (2006) - A computer virus connects the world of the living to the world of the dead.
Internal Moral RulesI am sure that these examples can be expanded quite readily and that these categories could be conceived of a bit more clearly.EX: The crew of the Enterprise cannot interfere with the denizens of Planet N, because of the Prime Directive (this is also an associative/reductive strategy, as it reflects the thudding moral relativism of 20th century anthropologists).Internal Physical Rules
EX: Immortals cannot fight on holy ground in Highlander. Why? Is there a God? What in the Zeist is this?
EX: You can kill demons in Demon Knight by stabbing or shooting their eyes, but this rule is subverted in the 3rd act when Billy Zane gets eye-balled, but doesn't die. This, however, is revealed to be a rule of which our heroine was unaware.
"Yeah, that eye-ball bull*** only works on lower level demons. I know! Who makes up these rules?"