Le pragmatisme peircéen, la théorie des catégories et le programme de Thiel

Abstract

Category theory is important by its mathematical applications and by the philosophical debates it causes. It is used to express in algebraic topology, to deduce in homological algebra and, as an alternative to the theory of sets, to construct objects in Grothendieck’s conception of algebraic geometry. Category theory is a fundamental discipline in Christian Thiel’s sense, because it is a theory of some typical operations of structural mathematics. This thesis is defended through a particular interpretation of peircean pragmatism; in this perspective, justification of mathematical knowledge is not provided for by the reduction to basic objects but rather by a technical common sense intervening on each level (the theories on the higher level having as their objects the theories of the original objects).