28.11.2019

Vortrag: Prof. Dr. Alexandra Zinke

Ort: Wilhelm-Schickard-Institut für Informatik, Sand 13, Raum A104
Datum: Donnerstag, 28.11.2019
Zeit: 18 Uhr c.t.
Thema: "Still in Harmony? On Demarcation Criteria for Logical Terms"

Oberseminar Logik und Sprachtheorie.

Abstract:

The talk criticizes the most prominent semantic demarcation criterion for logical terms, the classical invariance criterion. To that end, I will introduce an operator (call it ‘BULLET’) with an invariant extension that cannot be accepted as a logical term, as this would have the following fatal consequence: for any arbitrary true contingent sentence K of the metalanguage, there would be a logically true object-language sentence ‘φ’ such that K follows from the sentence ‘φ is true’.

The talk also explores whether BULLET satisfies standard harmony conditions on logical terms, and thus whether it provides a similar challenge for proof-theoretic demarcation criteria.