Logica Universalis Webinar April 24, 2024 at 4pm CET Speaker: Ori Milstein https://philpeople.org/profiles/ori-milstein Title: "Why the hexagon of opposition is really a triangle: logical structures as geometric shapes" Abstract: "This paper suggests a new approach (with old roots) to the study of the connection between logic and geometry. Traditionally, most logic diagrams associate only vertices of shapes with propositions. The new approach, which can be dubbed ’full logical geometry’, aims to associate every element of a shape (edges, faces, etc.) with a proposition. The roots of this approach can be found in the works of Carroll, Jacoby, and more recently, Dubois and Prade. However, its potential has not been duly appreciated, probably because of the complexity of the diagrams in these works. The following study demonstrates how the Hexagon of Opposition can be represented as a triangle and Classical Logic as a tetrahedron (rather than a rhombic dodecahedron). It then applies the approach to modal logic, extending the tetrahedron for the logic KT into a dipyramid and a cube for KD, and finally an octahedron for K. Some possible directions for further research are also indicated.." https://link.springer.com/journal/11787 Associate event World Congress on the Square of Opposition SQUARE 8 - Costa Rica Sept 6-13, 2024 https://sites.google.com/view/square8-2024 Presented by Pablo Villalobos Morera and Lorenzo Boccafogli Chair : Arnon Avron https://www.cs.tau.ac.il/~aa/ Editorial Board LU Everybody is welcome to join, register here: https://cassyni.com/events/VF7GYYaHGPGZiFeSZDibRX Jean-Yves Beziau Editor of Logica Universalis and Organizer of LUW https://philpeople.org/profiles/jean-yves-beziau