->''"There are ''no'' inconsistencies in the ''Literature/{{Discworld}}'' books; occasionally, however, there are alternate pasts."''
-->-- '''Creator/TerryPratchett''' on alt.fan.pratchett, wearing his Watsonian hat.

->''"Maybe the Patrician in ''Discworld/TheColourOfMagic'' was Vetinari, but written by a more stupid writer?"''
-->-- '''Creator/TerryPratchett''' on alt.fan.pratchett, wearing his Doylist hat.

When a creator answers a question about their work, should they provide an InUniverse answer or a RealLife answer? The former is the Watsonian perspective, the latter Doylist.

'''Watsonian''' or '''in-universe''' commentary restricts itself to making statements that are sensible within the story's reality. Watsonian explanations are things like "Character X was lying", "He had plastic surgery over the summer", and "The main character fell off a cliff". A more precise technical term for this is ''intradiegetic''. Tropes which take a generally Watsonian perspective include:
* AnthropicPrinciple
* AuthorsSavingThrow
* {{Retcon}}
* Some forms of DeathOfTheAuthor
* FanWank
* JustifiedTrope
* The many justifications that follow {{Headscratchers/Headscratchers}}.
* WildMassGuessing

'''Doylist''' or '''out-of-universe''' commentary considers the work as a created object, and prefers explanations based on the real-world motivations or circumstances of the creators. Doylist explanations are things like "The author had a better idea", "The actor died, so they had to hire a new one", and "The author got sick of writing those books, so he killed off the main character". A technical term for this is ''extradiegetic''. Doylist tropes include:
* AuthorExistenceFailure
* DependingOnTheWriter
* ForgotAboutHisPowers
* IdiotBall and all its subtropes
* TheLawOfConservationOfDetail
* RealLifeWritesThePlot
* RuleOfIndex and all its subtropes
* ExecutiveMeddling
* EnforcedTrope

The terms reference ''Literature/SherlockHolmes'': Watsonian commentary relates to the [[LiteraryAgentHypothesis in-universe author]] Dr. Watson, while Doylist commentary relates to the RealLife author Creator/ArthurConanDoyle. However, they seem to have originated (or at least been popularized) on the Creator/LoisMcMasterBujold fan mailing list.

A modern example might be the proliferation of RubberForeheadAliens in ''Franchise/StarTrek''. It is revealed in a ''Series/StarTrekTheNextGeneration'' episode that an ancient humanoid race "seeded" the galaxy with their genes, thereby causing humanoid intelligent life to evolve independently throughout the Milky Way. This is the Watsonian explanation. The Doylist explanation is that RubberForeheadAliens are cheap to produce, require relatively little imagination, allow the audience to easily read the emotions of alien characters, etc. (And budget was always a concern for ''Franchise/StarTrek''; when Klingons first exhibited the RubberForeheadAliens trope it was an ''improvement'' on their previous make-up!)

When PlayingWithATrope, note that sometimes a Doylist explanation is interjected purposely into a narrative; for example, in ''Film/MontyPythonAndTheHolyGrail'' the Knights of the Round Table (or what is left of them) are chased by the Legendary Black Beast of "AAAAAAAARGH" in the common surreal Creator/TerryGilliam style transitional animation, and are eventually cornered with no chance to escape. What saves them? The animator suffers from a fatal heart attack. On a less absurdist note, the LiteraryAgentHypothesis is a way of smuggling Doylist explanations into a Watsonian paradigm by introducing a fictional author. And finally, most creators don't stick to strictly one interpretation, as the pagequotes from [=PTerry=] suggest.

Conversely, some authors acknowledge that they don't have complete hold over the characters they've created and allow them to operate on their own logic - which is an example of Watsonian perspective influencing Doylist one.

In the German-speaking fandom of the ComicBook/DisneyDucksComicUniverse, the two ways of analyzing the stories are called ''Donaldismus literaricus'' (which treats the work of Creator/CarlBarks and others as works of art and literature) and ''Donaldismus archaeologicus'' (which treats them as factual reports from the Earth-like planet called ''Stella Anatium'' - the Star of the Ducks). In the D.O.N.A.L.D. (''Deutsche Organisation Nichtkommerzieller Anhänger des lauteren Donaldismus'' = German Organization of Non-Commercial Adherents of True Donaldism) the latter tends to dominate. Franchise/DonaldDuck comics are SeriousBusiness, definitely.