Revisiting Interpolation in Relevant Logics

Wesley Fussner; Andrew Tedder

doi:10.18778/0138-0680.2026.21

Authors

Wesley Fussner Institute of Computer Science of the Czech Academy of Sciences, Prague, Czech Republic Author https://orcid.org/0000-0002-6025-8770
Andrew Tedder Ruhr University Bochum, Department of Philosophy I, Bochum, Germany Author https://orcid.org/0000-0002-2303-003X

DOI:

https://doi.org/10.18778/0138-0680.2026.21

Keywords:

relevant logic, variable sharing property, Maehara interpolation, amalgamation, transferable injections property

Abstract

There are exactly two maximal schematic extensions of the relevant logic \(\mathcal{R}\) with the variable sharing property. We establish that one of them has a strong form of interpolation for deducibility, thereby giving an example of a well-known relevant logic with interpolation.

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