 Our discussion has revealed several different issues, of which we will highlight three as components of the ‘absolute-relative debate’. (i) There is the question of whether all motions and all possible descriptions of motions are equal, or whether some are ‘real’ – what we have called, in Seventeenth Century parlance, ‘true’. There is a natural temptation for those who hold that there is ‘nothing but the relative positions and motions between bodies’ to add ‘and all such motions are equal’, thus denying the existence of true motion. However, arguably – perhaps surprisingly – no one we have discussed has unreservedly held this view (at least not consistently): Descartes considered motion ‘properly speaking’ to be privileged, Leibniz introduced ‘active force’ to ground motion (arguably in his mechanics as well as metaphysically), and Mach’s view seems to be that the distribution of matter in the universe determines a preferred standard of inertial motion. In general relativity there is a well-defined distinction between inertial and accelerated motion, given by the spacetime metric, but Einstein initially hoped that the metric itself would be determined in turn by relative locations and motions of the matter distribution in spacetime.