Aleksander Domosławski

Epistemicism explains ignorance due to vagueness through semantic plasticity: the propensity of intensions of vague terms to shift across close linguistic communities. In the case of moral vagueness, e.g. when it’s vague whether it’s permissible to terminate a pregnancy after a certain number of days, epistemicism predicts that ‘permissible’ denotes distinct properties in different close linguistic communities. This epistemicist prediction has been pressured by arguments due to Miriam Schoenfield (2016) as well as certain interpretations of the Moral Twin Earth cases. Schoenfield (2016) argues that epistemicist account of moral vagueness leads to an unfeasible treatment of moral deliberation. A related worry comes from the Moral Twin Earth cases, which produce the intuition that the reference of moral terms such as ‘permissible’ remains stable across different linguistic communities. The problem for epistemicism is that metasemantic models that are meant to account for the Moral Twin Earth intuitions, such as the models proposed by Robbie Williams (2018) or Billy Dunaway and Tristram McPherson (2016), predict that moral vocabulary is stable, which makes them incompatible with epistemicism. My aim is to make use of the inferentialist metasemantic framework presented by Robbie Williams (2018), and I refine it to give an epistemicist account of moral vagueness.

In this paper, I present a novel problem for the interpretation of Leibniz’s discourse about possible individuals (e.g. possible ‘Adams’). Possibilia play an important role in Leibniz’s philosophy: they allow him to account for freedom and contingency present in the world. I attempt to square Leibniz’s discourse about possibilia with his theory of truth and the infinite analysis conception of modal notions. It turns out that this is not a straightforward matter: I argue that identity statements such as ‘Caesar is Caesar’ present a key challenge for this task. I consider a few options with regards to the interpretation of Leibnizian discourse about possibilia and I argue that the most charitable interpretation (also supported by textual evidence) makes use of a counterpart relation based on similarity (akin to Lewis 1968).

The epistemicist theory aims to explain ignorance due to vagueness by semantic plasticity: the shiftiness of intensions across close possible worlds resulting from shiftiness in usage. This explanation is challenged by the Omniscient Speaker Puzzle (Sennet in Philos Stud 161(2):273–285, 2012). Suppose that an omniscient speaker, Barney, who knows all the facts about usage and how these facts determine the intensions of expressions, cooks up a scheme to stabilise the intension of a normally semantically plastic term like ‘rich’. It seems that ‘rich’ would display all the phenomena associated with vagueness without being semantically plastic, thus making the epistemicist explanation of ignorance due to vagueness insufficient. In this paper, I present a few choice points for epistemicism that arise as a result of the puzzle.

Epistemicism associates vagueness with ignorance produced by semantic plasticity: the shiftiness of intensions in our language resulting from small changes in usage. The recent literature (Caie 2012; Magidor 2018; Yli-Vakkuri 2016) points to a missing piece in the epistemicist theory of vagueness, namely a clear account of the semantics of the definiteness operator Δ. The fundamentals of the epistemicist theory are well understood. However, the technical work of defining the definiteness operator has proven difficult. There are several desiderata that we would like Δ to satisfy. For instance, we would like the epistemicist notion of ‘definiteness’ to interact well with modal operators and validate intuitive principles like ‘necessarily, if φ is definitely true, then φ is true’. Providing an account that would meet all such desiderata has eluded the epistemicists so far. In this paper, I present a novel version of a multidimensional model inspired by the work of Robert Stalnaker and David Kaplan. Using this model, I provide an account of epistemicist definiteness that meets our desiderata.