A reappraisal of Poincare’s Geometrical Conventionalism

Abstract

Janet Folina has proposed an interpretation of Poincaré’s conventionalism against Michael Friedman and Robert DiSalle. They both state that Poincaré’s proposal is refuted by general relativity, since it implies a restrictive notion of a priori principles. Folina claims that Poincaré’s conventionalism is not in conflict with general relativity, because from Poincaré’s proposal it is possible to extract a relativized notion of a priori principles. We intend to show that Folina’s strategy is ineffective, since Poincaré cannot explain the role of Riemann manifold in general relativity. We will conclude that the attempt to reconstruct the development of general relativity from Poincaré’s philosophy may be an obstacle to understanding the radical nature of the change that relativity brought to the relationship between physics and geometry.