Logical Consequence

17-30 July 2023

Title of the course: Logical Consequence
Instructor: Prof. Alexei Muravitsky
Institution: Northwestern State University of Louisiana
Dates: 17-30 July 2023
Prerequisites: An introductory course in mathematical logic is a plus; otherwise, some familiarity with the understanding of mathematical proofs and their implementation is expected.
Level: Graduate, advanced undergraduate
Abstract: The concept of logical consequence in formal languages will be discussed. Most languages in focus will be propositional, but we will also consider first-order language as an auxiliary tool. The following topics will be covered: formal languages and their semantics; logical matrices (the following examples of logical matrices will be presented: the two-valued matrix, the Lukasiewicz three-valued matrix, the Lukasiewicz three-valued matrix with modality, the Gödel n-valued matrices, the Dummett denumerable matrix, the Lukasiewicz denumerable matrix. An implementation of the logical consequence will be presented as a consequence relation and as a consequence operator, and various types of realization of the consequence relation will be discussed, including definitions by closure systems, by logical matrices, and by inference rules. The following theorems will be proved: Lindenbaum’s theorem, Los-Suszko-Wojcicki’s theorem and Wojcicki’s theorem. If time permits, the concept of Lindenbaum-Tarski algebra will be discussed. Prerequisite: A rudimentary acquaintance with the meaning, as opposed to the technique, of ordinary symbolism of abstract algebra and mathematical logic, although perhaps not strictly necessary, is nevertheless advantageous.
Language: EN
Textbook: I’ll be closely following the chapters 3—5 of the book A. Citkin & A. Muravitsky, “Consequence Relations: An Introduction to the Lindenbaum Tarski Method”, Oxford University Press, 2022. Unfortunately, I don’t have an e-copy of the book, but I’ll bring an e-copy of our tutorial at the 6thUniversal Logic School, which I am going to share with students.