Abstract

The standard definition of an instantaneous temporal part cannot properly deal with cases involving time travel. This paper provides a new definition of an instantaneous temporal part by appealing to David Lewis's distinction between external time and personal time. The new definition avoids the problems because it does not allow more than one instantaneous temporal part of an object at each moment of its personal time. We argue that this new definition, combined with our new perdurantist semantic thesis, deals with cases of time travel successfully