Diodorus Cronus on Present and Past Change

abstract:Diodorus Cronus reportedly denied that there are truths about present kinēsis (change or movement) but affirmed that there are truths about past kinēsis. Although scholars have argued that Diodorus's atomism about bodies, place, and time supports his rejection of present spatial movement of simple bodies, I argue that Diodorus rejected a broader range of present changes, including qualitative and existential change. I also argue that Diodorus rejected these three sorts of change not only for simples but also for complexes. Furthermore, philosophers since antiquity have claimed that denying truths about present change is incompatible with accepting truths about past change, since each past truth about change corresponds to some present truth about change. I argue that this objection can be overcome. I conclude that Diodorus's arguments against present change are both broader and more successful than is usually maintained.