This investigation on the origin and meaning of the Cartesian doctrine of the creation of eternal truths aims to highlight the gap that separates Descartes and Montaigne on the subject of truth and God’s omnipotence. While, from a theological perspective, Montaigne insists that human reason cannot know things as they are in themselves (or in their essence), Descartes insists on the contrary, within a perspective of articulation between physics and metaphysics, that human reason can know things as they are in themselves (or in their essence). Descartes’ physics indeed rests on a double affirmation: that God can bring into existence what he himself makes possible (or conceivable), and that God cannot bring into existence what he makes impossible (or inconceivable). The aim of this paper is to refute the interpretation drawn from Jean-Luc Marion according to which the Cartesian doctrine of the creation of eternal truths is equivalent to an "out coding" of the intelligible.