When I say that everything exists and the neo-Meinongian denies that everything exists, we’re not talking past each another—not, at any rate, because we mean different things by ‘everything’. It is precisely because the neo-Meinongian knows that I mean just what he does by ‘everything’ that he indignantly rises to dispute my contention that everything exists.This is not a hundred miles from what I argued here. Maverick philosopher also discusses Inwagen's paper here, though I confess I don't understand his objections to it. The force of Inwagen's paper is neo-Meinongianism is a theory about the meaning of 'exists', rather than a theory about what exists.
I also found a paper by Amie Thomasson about fictional entities. She mentions, but rejects, the explanation of discourse about fiction by the use of a 'fiction operator'.
Internal discourse by readers can still be held to be true even though it involves non-referring names, since these claims are plausibly held to be implicitly prefixed with a fiction operator, where “According to the fiction, Holmes solved his first mystery in his college years” may be true even if the simple claim “Holmes solved his first mystery in his college years” would be false. Cross-fictional statements can be handled similarly by taking them to fall in the context of an ‘agglomerative’ story operator that appeals to the total content of the relevant stories, taken together, e.g. “According to (Anna Karenina and Madame Bovary [taken agglomeratively]), Anna Karenina was more intelligent than Emma Bovary”Fictional operator theories are attractive, and I will try to discuss them next week.