Seminars of the Department of Logic
In Defence of Proof-Theoretic
Semantics
Will Stafford
(Institute of Philosophy, Czech Academy of Sciences)
Proof-theoretic validity offers a justification for the logical laws. However, it has
recently been shown that proof-theoretic validity does not offer a semantics for
intuitionistic logic, but rather it provides a semantics for intermediate logics which isn’t
harmonious. But baked into the philosophical justification for proof-theoretic validity is
the idea that it results in a logic with harmonious rules. I show that the lack of
harmony stems from the treatment of atomic sentences, not from the treatment of
logical connectives. I propose a modification to proof-theoretic validity that will
remove the undue impact of atomic formulas. And I show that the logic justified by
the new definition is intuitionistic logic. Hence this modification saves proof-theoretic
validity from the above objection.
Thursday, February 18 at 14:00
Zoom Meeting:
cesnet.zoom.us/j/96869302116?pwd=bHlFektFMi9lZXBUeDd5WHM0RmE3QT09
Meeting ID: 968 6930 2116
Passcode: 082189