# Novel II — Worldbuilding: Consistency Engines
In ["Novel II — Worldbuilding: Setting as Character"](/harrys-desk/novel-ii-worldbuilding-setting-as-character) I said a place that only describes is wallpaper, and a place that wants something is a character. I asked you to write Document W — want, method, cost — and to keep the brochure out of the scene. If you did that work, you hired a second witness. Today we keep it from developing amnesia.
The claim is unfashionable because it sounds like homework. Consistency is not pedantry, and it is not a wiki. It is how a second witness stays a character instead of reverting to scenery the moment the scene changes key. A drought that wants the well unused by strangers has to keep wanting that on page three hundred, or the want was a mood. The model, which does not remember a well the way a body remembers thirst, will refill the aquifer because this chapter is a love scene, and love scenes, in the training data, happen near water.
By the end you should be able to name the facts that cannot move, catch the refill before it becomes lore, and tell a broken rule from a caused change.
The Want Has to Survive the Scene
Monday's portrait is a hiring document. It is not yet a character, because character is pattern over time. Eleanor's hope fails against Hill House more than once. The stillsuit on Arrakis is not a costume for the opening; it is a constraint that keeps costing conversation in open air. If it comes off because the scene would be prettier without it, Arrakis was wallpaper with a brand name.
This is the same problem we had with voice. In ["Finding the Narrator"](/harrys-desk/novel-ii-voice-and-style-finding-the-narrator) I said the model drifts toward the default generalist unless you keep a tuning fork. Worlds drift faster. The training data is full of places that exist for the length of a paragraph. A generated inn is consistent with inns. It is not consistent with *your* inn, which has no back door because the taxman used the last one.
Readers will not forgive a world that agrees with the scene's emotion. The well is dry when the plot needs hardship and full when two people need to wash. That is the brochure problem in temporal form. Weather-as-mood, which I asked you to strike on Monday, has a cousin: inventory-as-mood. Objects appear because the feeling wants them. Objects decided on page twelve vanish because the feeling does not.
Pedantry would be counting buttons on a uniform. I do not care about the buttons unless a character is late because of them. I care that the drought you hired does not take a holiday for a tender scene. Tenderness in a drought is interesting. Tenderness next to a sudden river is a postcard.
The Refill
Here is the AI accent of inconsistency, and it is more specific than "the model forgets."
The model does not forget the way a tired novelist forgets. A tired novelist has a body that was in the room. She writes the well dry, then three months later writes a bath, and when she reads the bath she feels the lie in her hands. The model has no hands. Each prompt is a new room with a short note on the door. If the note does not mention the well, the well is full, because full wells are the prior. Empty wells are a special case. Special cases expire when the prompt ends.
Four refill types show up in the drafts I see.
Mood-match. The scene is love, or rest, so the world softens. Rain stops. Food appears. Patrols thin out because intimacy, in the corpus, happens in private. Your Document W said the patrols do not thin. The model never saw the page.
Completeness. You asked for a chapter, so the model supplies a functioning environment: water, light, a door that opens. A world under constraint looks, to an assistant, like an incomplete world. The assistant completes it. That is the same completeness that smuggled encyclopedia into Monday's openings. Completeness is a virtue in a tool. It is how a drought dies.
Local exception. You did mention the well. The model honors it for a sentence, then grants a cistern, a hidden spring, a neighbor who "somehow" has a barrel. The constraint is acknowledged so it can be escaped. You hired a cost. A scene that spends the cost and then refunds it has no cost.
Borrowed weather. The model reaches for a climate that belongs to another book in the neighborhood of your prompt. Desert stories get two moons. Harbour stories get fog. None of this is your want. It is genre furniture walking in because the prompt was thin and the prior is thick.
In ["Hallucination, Confabulation, and the Limits of Generation"](/harrys-desk/hallucination-confabulation-limits) I said the model will invent a plausible fact rather than admit a gap. Worldbuilding inconsistency is that habit pointed at your own bible. The invention is locally plausible. It is globally a lie about a place you already decided.
Do not fix this by pasting Document W into every prompt. The model will smuggle: a character will think, helpfully, about aquifer policy in language no one at the well would use. The engine does not live in the prompt. It lives in the pass you run after.
Physics, Politics, Texture
You do not need a taxonomy to write. You need to know which facts are allowed to move, because the model treats all facts as equally negotiable.
Physics: what cannot change without the book becoming a different book. The well is dry. The hill eats sound. Names, in Earthsea, have cost. Orogeny, in *The Fifth Season*, is not a metaphor you set down for a love scene. If you change physics because a chapter is inconvenient, you swapped worlds. Readers who have been paying attention will feel the floor move. Once they stop trusting the second witness, atmosphere will not get them back.
Politics: what can change, but only if someone pays. Who owns the water. Which door no one uses. The rumor of the gallery at Hailsham. These are allowed to move. They are not allowed to move because the prompt was in a softer register. A caused change is plot. An uncaused change is refill. The test is ugly and it works: can you point to the scene where the cost was paid? If the answer is "it is implied," it is not implied. It is missing.
Texture: the rest. The name of the inn. The color of the tram. Texture can drift if nobody used it. Texture that *was* used is no longer texture. It has been promoted, by the reader's memory, into physics. The mill whistle in chapter one is physics by chapter six, whether you meant it to be or not. This is why you do not let the model rename the inn for variety. Elegant variation is a prose habit. In a world it is a crack.
Tolkien's moon phases are famous because they are slightly mad. They are also a physics decision: the sky is not mood lighting. Le Guin's winter, in *The Left Hand of Darkness*, is not a theme you lift for the travel chapters. The cold is the politics. If you take it off, Karhide is a different country.
I am not asking you to become a continuity clerk for buttons. I am asking you to know, before you generate chapter nine, which of Monday's constraints have been promoted. The engine tracks promotions. That is most of the job.
The Ledger, Not the Wiki
A wiki is a completeness machine. It wants every proper noun to have a page. That is a reasonable tool for a television room with twelve people. It is a trap for a novelist with a model, because the model loves wikis. Wikis look like knowledge. Knowledge looks like something you should put in the prompt. You already know what happens then.
A consistency engine is smaller and meaner. After each chapter, model closed, five lines:
What the place still wants. Which physical constraints appeared on the page. Which of those are now promoted — the reader has seen them, so they cannot quietly vanish. Whether anyone paid a political cost, and what the new cost is. Where the model, or you, refilled.
That last line is the one people skip, because it feels like catching yourself cheating, and it is. Catch it. The bath in the drought, the patrol that thinned: write them down as refills, not as flavor. Flavor is how refill asks to stay.
Keep the ledger next to Document W, not inside it. Document W is the hiring portrait. The ledger is the employment record. Mixing them produces a bible that grows in every direction and cannot be checked. An unread bible is wallpaper with footnotes.
A miniature, because the method is easier to steal than the slogan. Chapter three left you this: well low; window faces the mill; patrols at dusk; the town wants the accident unspoken. You generate a reunion in the kitchen. What arrives is rain, a cistern that had "somehow" held, no patrols, and a river she can look at while she talks. Four refills. Strike all four. Put the whistle at six through a line of dialogue. Leave the tap dry and the mill in the window. The reunion now has to happen under constraint. That is a scene. The other was a kitchen from stock.
You may use the model as a checker once the chapter exists. Paste the chapter and the five-line ledger from the *previous* chapter — not the wiki — and ask where the world got easier than the ledger allowed. Do not ask "is this consistent." Consistent, to the model, means locally smooth. Smooth is the refill. Then you verify. The model will flag real refills and also flag texture it does not remember. You are the judge.
In ["Version Control for Writers — Managing AI-Assisted Drafts"](/harrys-desk/version-control-for-writers-managing-ai-assisted-drafts) I said drafts need a history because the present file will lie about its past. Worlds need the same. The ledger is version control for pressure. If you cannot see what the well was two chapters ago, you will believe the full well in front of you.
The Prompt That Causes It
Most refill is not mystical. It is a prompt that asked for a scene without constraints, or a prompt that asked for atmosphere.
"Write the reunion in the kitchen" will get you a kitchen from stock. Your kitchen faces the mill, the well is low, the whistle goes at six. None of that arrives unless you put the constraints in — not the lore, the constraints. Two or three. That is Document S from Monday. Use it. Then run the ledger. The prompt reduces refill. It does not replace the pass.
"Make this more atmospheric" is a refill request. Atmosphere is what you have when you have not chosen a pressure. The model will add weather, odor, and a piece of history. History is almost always a completeness leak. Weather is almost always mood. Strike the request. Ask what the place prevents in the next two minutes, and write that.
The third prompt is the dangerous one because it sounds like craft: "Given the world bible, write chapter nine." You have now put Document W in the room with a completeness-seeking machine. The chapter will explain the town. The well will be mentioned so that it can be solved. This is the smuggle. Chapter nine gets the scene prompt and the two or three constraints that actually touch these pages. The bible stays on your desk.
In ["First Draft by AI, Revision by Human — A Workflow"](/harrys-desk/first-draft-by-ai-revision-by-human-a-workflow) I said the human pass is where decisions live. Consistency is a decision against the model's local smoothness. You cannot prompt your way into a memory the model does not have. You can only keep a record, and refuse the easier world.
A Broken Rule Is Not a Twist
There is a cheap move in speculative fiction, and the model is fluent in it: the rule you announced was never the rule. The desert had a river under it. The magic costs nothing if you are special. Readers experience this as a hat, the same hat I named when a limited narrator was reclassified, in the last twenty pages, as a liar. If the physics was not already doing the work, the reveal is a costume change.
A caused change is different. Someone pays. The well is sabotaged; we watched the sabotage. The gallery rumor is withdrawn; the children feel the obedience slip. The second witness is allowed to lose. It is not allowed to have been kidding.
When you find a refill you love — the bath, the hidden spring — you have a choice, and both choices are honorable. Strike it, and keep the drought. Or go back and *cause* it, in an earlier chapter, so the spring is not a gift from the prompt. What you may not do is keep the gift and call it mystery. Mystery is a pattern the reader can work. A refund is a pattern the writer hopes they will not notice.
In ["The Integrity Framework — A Writer's Code for AI Use"](/harrys-desk/the-integrity-framework-a-writers-code-for-ai-use) I said the writer is accountable for what the page finally is. If the well refills because you were tired and the model was fluent, you did that. Fluency is not memory.
For Next Time
On Friday we give the engine instruments you can hold: ["Novel II — Worldbuilding: Maps, Timelines, Glossaries"](/harrys-desk/novel-ii-worldbuilding-maps-timelines-glossaries). A ledger of five lines will get you through a chapter. A novel needs a few objects that are not prose: a map that refuses to grow a river, a timeline that refuses to let two armies occupy the same week, a glossary that refuses to let a word mean its opposite because the scene is tender. The model will offer to generate all three overnight. That offer is a wiki in three files. We will talk about which marks you make by hand.
Your homework until then: take Monday's Document W and the scene you already rewrote. Write the five-line ledger, model closed. Then generate the *next* scene — four hundred words, a different emotional register — from a scene prompt that contains two or three constraints, never the bible. Run the ledger against the new scene. Mark every place the world got easier. Strike the easy. If you cannot strike it without killing the scene, go back and cause it in the first scene instead of refunding it in the second. If the want from Monday is still audible, and more expensive, the engine is working. Bring the ledger on Friday. Maps are wasted on a world that will not keep its own word.
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*Harry Mercury, Editor in Chief* *The SMF Works Project* *Week 16, Article 2*