David Lewis’s analysis of “can” in “The Paradoxes of Time Travel” (Lewis, American Philosophical Quarterly, 13, 145–52, 1976) has been widely accepted both as a definitive analysis of “can” and as a successful resolution of the Grandfather Paradox for time travel. I argue that the central feature of his analysis puts it on all fours with a fallacy frequently imputed to fatalists such as Richard Taylor. I go on to consider two moves that might be made to avoid the fallacy, (...) arguing that one of them leads to the unavailability of an all-things-considered “can” and the other to a new primitive modality, not analyzable in Lewis’s way. (shrink)

David Lewis’s analysis of “can” in “The Paradoxes of Time Travel” has been widely accepted both as a definitive analysis of “can” and as a successful resolution of the Grandfather Paradox for time travel. I argue that the central feature of his analysis puts it on all fours with a fallacy frequently imputed to fatalists such as Richard Taylor. I go on to consider two moves that might be made to avoid the fallacy, arguing that one of them leads to (...) the unavailability of an all-things-considered “can” and the other to a new primitive modality, not analyzable in Lewis’s way. (shrink)

In his well-known time travel story, David Lewis claims that there is a sense in which Tim can go back in time and kill his Grandfather and a (more inclusive) sense in which he cannot. Lewis describes Tim’s predicament as semi-fatalist, but holds that this does not compromise Tim’s freedom or his ability to kill Grandfather. I argue that if semi-fatalism is true of Tim, it is true of everyone, and that this is a troubling conclusion.