Abstract

The author argues that Newton’s distinction between absolute and relative motion, i.e. the refusal to define motion in relation to sensible things, in “Scholium on time, space, place and motion” from _Mathematical Principles of Natural Philosophy_, stems in great part from his critical stance towards Descartes’s philosophy of nature. This is apparent from the comparison of “Scholium”, in which Descartes is not mentioned at all, with Newton’s criticism of him in his manuscript _De gravitatione_. The positive results of Newton’s encounter with Descartes’s theory of motion is almost completely identical to those of the “Scholium”: the definition of motion must concern the whole body and not just its surface; instead of “mutual translation”, it must include the force that is the cause of the physical motion; the motion of the bodies is uniform and straightforward, which can only be achieved within absolute space. As far as the theory of motion is concerned, Newton’s philosophical challenge was always Descartes.