This article sets out to prove that experience plays a central role in Cartesian science and, therefore, that Descartes is willing to let go of some theoretical assumptions in order to accommodate scientific observations. My point is that Descartes' commitment to scientific observation is so strong that in the study of magnetism, he chooses not to keep his system not completely consistent when he adopts a magnetic property (a property that was observed by several scientists, especially Gilbert) that contradicts the law of conservation of quantity of motion in order to keep in touch with empirical observations. This commitment to experience further strengthens the notion that Descartes was not indifferent to the empirical observations of his time, and actually engages in scientific work that tries to adapt itself to them.
Descartes; Method; Magnetism; Natural laws; Experience
