Reconsidering Logical Principles: First Principles and Parameters of Rationality

• Grant number: 24/13530-2
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Start date: January 01, 2025
• End date: December 31, 2026
• Field of knowledge: Humanities - Philosophy - Logic
• Principal Investigator: Edelcio Gonçalves de Souza
• Grantee: Felipe Gustavo Alves Moreira
• Host Institution: Faculdade de Filosofia, Letras e Ciências Humanas (FFLCH). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

Two theses still widely shared today go as far back as to Aristotle; that logical principles, such as the Principle of Non-Contradiction and of the Third Middle are: first principles that cannot be justified but justify all other principles; and universal parameters of rationality whose rejection inevitably leads to socially negative consequences. The premise that logical principles are, as Carnap puts it, "tautologies" grounds traditional and still popular arguments for these theses. Our project, by its turn, defends a perspective not much explored in philosophy of logic. The perspective is that, in light of the fact that throughout the 20th century, there have been created non-classic logics, such as the paraconsistent ones of da Costa and the intuitionistic logic of Heyting, the stated premise and theses should be rejected and two hypotheses deserve attention. The first hypothesis is that logical principles need to be justified by not properly logical factors, e.g., metaphysical or political ones. The second hypothesis is that the rejection of the alleged universality of a traditional logical principle can be "liberating" in a sense closely related to that which philosophers of liberation like Dussel give to this term. So, the objective of our project is to defend these two hypotheses.