Abstract

Cartesian dualism and the union of mind and body are often understood as conceptions that contradict each other. Diachronic interpretations maintain that Descartes was first a dualist and later on developed his stance on the union of mind and body. Some authors find here a problem without solution. Nevertheless, in the last two decades, some interpretations have been developed intending to give a positive solution to the difficult relation between Cartesian dualism and the union of mind and body. The problem that I find in most of them is that they try to show no incoherence between Descartes' dualism and his conception of the union and interaction by "weakening" or making more "flexible" the dualist doctrine. I develop a synchronic interpretation, based on textual evidence, in order to show that dualism and union appeared simultaneously in Descartes' works. Under this perspective, my claim is that Cartesian radical dualism and the union of mind and body can be coherently understood only because they belong to different domains of knowledge. Thought and matter are clear and distinct primitive notions that come from reason, whose role is laying the foundations for Cartesian metaphysics and physics, while the primitive notion of union is acquired by the senses and lacks clarity and distinction even while it serves the objective of founding Descartes' moral philosophy.