Watsonian Versus Doylist

There are no inconsistencies in the Discworld books; occasionally, however, there are alternate pasts.

—Terry Pratchett on alt.fan.pratchett, wearing his Watsonian hat.

Maybe [the Patrician in The Colour of Magic] was Vetinari, but written by a more stupid writer?

—Terry Pratchett on alt.fan.pratchett, wearing his Doylist hat.

Watsonian or in-universe commentary takes the reality of a work as given, and thus restricts itself to making statements that are sensible within that 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:

Author's Saving Throw
Retcon
Some forms of Death of the Author
Fan Wank
Justified Trope
The many justifications that follow Headscratchers.
Wild Mass Guessing

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:

The Literary Agent Hypothesis is a way of smuggling explanations that would otherwise be Doylist into a Watsonian paradigm, by introducing a fictional author.

As the page quotes suggest, most people aren't "pure" Watsonians or Doylists; they switch between modes as the occasion warrants. The terms reference Sherlock Holmes—where Watsonian commentary relates to the in-universe author Dr. Watson, while Doylist commentary relates to the Real Life author Arthur Conan Doyle—but they seem to have originated (or at least been popularized) on the Bujold fan mailing list.

A modern example might be the proliferation of Rubber Forehead Aliens in Star Trek. It is revealed in a Next Generation 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 a very Watsonian explanation. The Doylist explanation of the Rubber Forehead Aliens is simply that they are cheap to produce, require relatively little imagination, allow for the audiences to sympathize with alien characters, etc.

Sometimes a Doylist explanation is interjected purposely into a narrative; for example, in Monty Python and the Holy Grail 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 Terry Gilliam style transitional animation. Fortunately for the heroes, when there is apparently no chance of escape the narrator explains that the animator suffered from a fatal heart attack—a beast that arises out of nowhere and is killed by a surrealist Deus Ex Machina coming from a Doylist inclusion in the narrative.

Examples of Watsonian Versus Doylist include:

Comic Books

In German-speaking fandom of Disney's Duck comics, the two ways of analyzing the stories are called Donaldismus literaricus (which treats the work of Carl Barks 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. Donald Duck comics are Serious Business, definitely.

Fan Works

My Apartment Manager is not an Isekai Character: One character was magically twinned the in-universe day after she arrived. The Watsonian explanation is that she was alone, surrounded by people she was accustomed to thinking of as enemies, and desperate for somebody to talk with who understands her; the Doylist explanation is that two writers wanted to write the same character.
- Similarly, one short-short story was written to give a Watsonian explanation for why Haruhi Suzumiya doesn't appear in the setting (despite being admirably suited to it), when the Doylist explanation is simply none of the authors wanted to write anything with her and her supporting characters.