Sophie Nagler (New College): Proof-theoretic pluralism: co-determination on two levels
Theories of logical pluralism defend that there is more than one admissible logic. In this talk, I argue against the two-level logical pluralism in Ferrari and Orlandelli (2019). I also contend that it is incompatible with the co-determination logical pluralism in Dicher (2016). To accomplish this goal, I first introduce the two theories of logical pluralism from the perspective of proof-theoretic semantics. Particular attention shall be given to Belnap’s notion of harmony. Satisfying harmony will serve as an indispensable premiss of any admissible logic for all views discussed in this talk. I carve out the underlying theories of inference rules for both, the two-level view and the co-determination approach. By contrasting these, I argue that the former is incompatible with the latter. Additionally, I introduce a way of reconciling both views in the form of a refined two-level pluralism. Finally, I offer an alternative reading of the co-determination thesis and argue for a meaning-variant form of logical pluralism in the absence of compositionality.
Additional Information: Ockham will be held on MS Teams during MT20. Please email alexander.read@philosophy.ox.ac.uk if you wish to attend.
