Abstract

An assessment of Descartes’s relation to his Aristotelian contemporaries in his Regulae ad directionem ingenii—and more specifically his relation to the theory of scientific habitus—has never been undertaken and is long overdue. Despite broad scholarly consensus that Descartes rejected the scholastic theory of scientific habitus in the Regulae, I will show that, in fact, he redefines a centuries-old scholastic debate about the unity of science, and that he does so by employing, not rejecting, the concept of scientific habitus. For Descartes, the sciences are collectively one in virtue of a habitus which inclines the intellect to regard all things, not as they are in reality, but rather as they are relative to the intellect alone. Descartes establishes the unity of science via what Suárez refers to as “extrinsic denomination” in Disputationes metaphysicae 44.11.64. This creates a serious problem. As he no doubt knew and as Suárez would have rightly pointed out, the extrinsic denominations that Descartes employs in the Regulae have no ontological basis in the things denominated. Descartes’s method creates, arguably for the first time, a chasm between how things can be known by the intellect and how they are in reality—i.e., between “epistemology” and “ontology”—that motivates him to pursue metaphysics after the Regulae.