Time-Slice Rationality and Self-Locating Belief

Agreement and Updating For Self-Locating Belief

Suppose we have two ideally rational, perfectly introspective, individuals, who want to pool their information. Since both individuals are perfectly introspective, they are both in a position to characterize to the other exactly what they know. Suppose, then, that each tells the other what they know and each correspondingly incorporates this information into what they know. Given that such indi...

Four Problems about Self-Locating Belief

In this article I defend the Doomsday Argument, the Halfer Position in Sleeping Beauty, the Fine-Tuning Argument, and the applicability of Bayesian confirmation theory to the Everett interpretation of quantum mechanics. I will argue that all four problems have the same structure, and I give a unified treatment that uses simple models of the cases and no controversial assumptions about confirmat...

How to Reason about Self-Locating Belief

When reasoning about self-locating belief, one should reason as if one were a randomly selected bit of information. This principle can be considered to be an application of Bostrom’s Strong Self-Sampling Assumption(SSSA)[2] according to which one should reason as if one were a randomly selected element of some suitable reference class of observer-moments. The reference class is the class of all...

Agreement theorems for Self-Locating Belief

In this paper, I first outline Aumann’s famous “no agreeing to disagree" theorem, and a second related theorem. These results show that if two or more agents, who have epistemic and credal states that are defined over algebras that do not include any self-locating propositions, have certain information about one another’s epistemic and credal states, then such agents must assign the same creden...

Rationality, Belief and Commitment