 As we discuss further in the companion article, Mach attributed to Newton the fallacious argument that because the surface of the water curved even when it was not in motion relative to the bucket, it must be rotating relative to absolute space. Our discussion of Newton showed how misleading such a reading is. In the first place he also argues that there must be some privileged sense of rotation, and hence not all relative motions are equal. Second, the argument is ad hominem against Descartes, in which context a disjunctive syllogism – motion is either proper or ordinary or relative to absolute space – is argumentatively legitimate. On the other hand, Mach is quite correct that Newton’s argument in the Scholium leaves open the logical possibility that the privileged, true sense of rotation (and acceleration more generally) is some species of relative motion; if not motion properly speaking, then relative to the fixed stars perhaps. (In fact Newton rejects this possibility in De Gravitatione (1962) on the grounds that it would involve an odious action at a distance; an ironic position given his theory of universal gravity.)