Credence in the Image of Chance

In this article, I consider what sorts of chance credence norms can be justified by appeal to the idea that ideal credences should line up with the chances. I argue that the Principal Principle cannot be so justified but that an alternative norm, the Temporal Principle-which maintains that an agent's credence in a proposition phi, conditional on the temporal proposition that says that the chance of phi is x, should be x-can be so justified.