Most of the people who will ever live will probably live in the future, long after we are dead. Over them, we hold immense, unchecked power. What would it mean to exercise that power justly? For concreteness, I focus on the question of how much we should save on behalf of future generations and on attempts to solve this problem using Rawlsian social contract theory: i.e., by considering what principles rational, mutually disinterested persons would collectively choose when deprived of knowledge about how they personally fare under the terms of their collective agreement. I argue that we can solve a number of significant problems for the application of Rawlsian social contract theory to issues of intergenerational justice by assuming that the parties in the Original Position obey evidential decision theory. Furthermore, I argue that the application of evidential decision theory to the question of just saving is not at all ad hoc: there are strong independent reasons to think that Rawlsian social contract theorists ought to view the parties in the Original Position as obeying evidential decision theory.