I.F.P.A.R. RESEARCH SEMINARS (26 February 2026)
victorg, Monday 23 February 2026 - 00:00:00 //


Thursday, 26 February 2026, 12:00–14:00 
Speaker: CS III CONSTANTIN C. BRÎNCUȘ (I.F.P.A.R.)
Title: „Categoricity for the inferential ω-logic and Lω1,ω”
– online –
Meeting invite link:  https://meet.google.com/idm-boup-spy
*No registration required.

Abstract:
In this talk, I show that if a sentence φ of Lω1,ω is categorical, then the corresponding first-order theory Tφ is categorical if and only if its models satisfy the generalized inferential ω-rule. The result is established by first proving that Peano Arithmetic is categorical in inferential ω-logic. The talk is intended as a philosophical presentation of logical results from a paper co-authored with Professor John T. Baldwin. In addition to the technical results, the paper develops a philosophical view of mathematics—called cognitive modelism—according to which classical mathematics is a complex process of constructing and developing a distinctive class of concepts, rather than merely describing a fixed realm of structures.