Philosophisches Seminar



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.


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.