Relativism and Two Kinds of Branching Time

This essay examines the case for relativism about future contingents in light of a distinction between two ways of interpreting the ‘branching time’ framework. The first step of the relativist argument is to argue for the ‘Non-Determination Thesis’, the view that there is no unique actual future. The second step is to argue from the Non-Determination Thesis to relativism. I show that first step of this argument fails. But despite that result, the second step is still of interest, since one might hold the Non-Determination Thesis on alternative grounds. I then argue that whether the second step of the argument succeeds depends on how the branches in question are interpreted. If the branches are ersatz possible worlds, then the argument for relativism might go through. But if the branches are concrete parts of a ‘branching multiverse’, then the argument for relativism turns out to make implausible assumptions about the nature of personal identity over time.