Taking language across the divide, from a natural, organic system that functions, however inexplicably, at worlds, to a formal logical system is itself a complex matter of translation. The gulf between natural language and formal systems of logic is navigable only by giving something up, translating in either direction. The problem is best exposed by reference to the degree of nuance available in natural language in writing fiction and talking about it. Even with no firm guarantee that natural language means anything at all, a dialogue can be thrown together at a moment’s notice about the possibility, potentiality, plausibility, or proximity of fictional states of affairs. Complex and only minimally dissimilar concepts are immediately available and distinguishable. Developing a formal structure that gets some of the same concepts up and running is a much more arduous task.
It is best to avoid claims that suggest the bridge between the natural language in which fictional texts occur and the formal language by which they are analysed has properly been crossed. Fiction is (almost always) composed in natural language and almost always talked about this way. The formalisation of tropes of fiction is a process of abstraction that has purpose in examining patterns in language and the rhetorical effects of texts at worlds. It is possible to think about fiction logically, for the fruits this yields although fiction employs natural, usually poetic, forms of discourse that forego the precise, well grounded but less flexible sorts of meaning afforded by logical discourse. But the full import or complexity of natural language in fiction is not captured by this process.