Modal fictionalism

Modal fictionalism is a term used in philosophy, and more specifically in the metaphysics of modality, to describe the position that holds that modality can be analysed in terms of a fiction about possible worlds. The theory comes in two versions: Strong and Timid. Both positions were first exposed by Gideon Rosen starting from 1990.

According to strong fictionalism about possible worlds (another name for strong modal fictionalism), the following bi-conditionals are necessary and specify the truth-conditions for certain cases of modal claims:

Recent supporters of this view added further specifications of these bi-conditionals to counter certain objections. In the case of claims of possibility, the revised bi-conditional is thus spelled out: (1.1) it is possible that P iff At this universe, presently, the translation of P into the language of a fiction F holds according to F.

According to a timid version of fictionalism about possible worlds, our possible worlds can be properly understood as involving reference to a fiction, but the aforementioned bi-conditionals should not be taken as an analysis of certain cases of modality.

This objection can be spelled out in at least two ways: artificiality as contingency or artificiality as lack of accessibility.

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