Abstract
In this paper we use proof-theoretic methods, specifically sequent calculi, admissibility of cut within them and the resultant subformula property, to examine a range of philosophically-motivated deontic logics. We show that for all of those logics it is a (meta)theorem that the Special Hume Thesis holds, namely that no purely normative conclusion follows non-trivially from purely descriptive premises (nor vice versa). In addition to its interest on its own, this also illustrates one way in which proof theory sheds light on philosophically substantial questions.
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Open Access funding enabled and organized by Projekt DEAL. Gefördert durch die Deutsche Forschungsgemeinschaft (DFG) - Projektnummer 459928802. Funded by the German Research Foundation (DFG) - Project number 459928802.
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Gratzl, N., Pavlović, E. Is, Ought, and Cut. J Philos Logic (2023). https://doi.org/10.1007/s10992-023-09701-y
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DOI: https://doi.org/10.1007/s10992-023-09701-y
Keywords
- Special Hume thesis
- Is-Ought argument
- Sequent calculus
- Subformula property
- Deontic logics