I am looking for the word that refers to the set of rules/laws within a fictional universe which maintains the realism within the universe [closed]

I am looking for the word that refers to the set of rules/laws within a fictional universe which maintains the realism within the universe.

Eg. Within The Lord of the Rings it is established that magic, elves, trolls etc are all realistic within this fantasy universe as it is established early on in the story, however, were Frodo to suddenly pull out a mobile telephone and let Gandalf know he was on his way to Mt Doom it would be unrealistic within the universe.

Words that it is not:

• Realism
• World building
• consistency
• plausibility

I seen it for the first time in a forum I can no longer find. All synonyms of realism are not what the word is either. I believe it to be specific to rules/laws within fictional/alternate universes created that maintain the status quo of realism.

I apologise if this is unclear but cannot think of another way to explain it and simply hope someone reading this knows the word.

Solution 1:

It's not a single word but I think the term you're looking for is internal logic or internal consistency.

https://www.matthewmarchitto.com/blog/2016/3/22/worldbuilding-part-3-internal-logic

https://tvtropes.org/pmwiki/pmwiki.php/Main/Consistency?from=Main.InternalConsistency

Solution 2:

I think an apt term would be [generic] verisimilitude.

From Wikipedia (emphasis in original):

Verisimilitude is the "lifelikeness" or believability of a work of fiction...Language philosopher Steve Neale distinguishes between two types: ...cultural verismilitude, meaning plausability...outside of the work; and generic verismilitude, meaning plausibility...within the bounds of its own genre."

Other related terms are mimesis and diegesis.

Further in the Verismilitude article, Wikipedia states:

Verisimilitude has its roots in both the Platonic and Aristotelian dramatic theory of mimesis, the imitation or representation of nature. For a piece of art to hold significance or persuasion for an audience, according to Plato and Aristotle, it must have grounding in reality.

Here's a contrast between these 2 terms in the Diegesis article:

Diegesis (Greek διήγησις "narration") and mimesis (Greek μίμησις "imitation") have been contrasted since Plato's and Aristotle's times. Mimesis shows rather than tells, by means of action that is enacted. Diegesis is the telling of a story by a narrator. The narrator may speak as a particular character, or may be the invisible narrator, or even the all-knowing narrator who speaks from "outside" in the form of commenting on the action or the characters.