The Relativity of Motion as a Motivation for Leibnizian Substantial Forms

Richard Arthur (McMaster University, Hamilton, Ontario, Canada), in Substantial forms, points of view, and the relativity of motion, argues that one of Leibniz’s motivations for reintroducing substantial forms was to save the reality of motion. Already in 1676 Leibniz had established that motion, understood geometrically (i.e. as change of situation), is merely relative, and therefore a pure phenomenon or appearance. True motions, on the other …