Reflection and Self‐Trust

The Reflection principle expresses a kind of epistemic deference to one's future self. There is a plausible intuitive argument to the effect that, if one believes one will reason well and gain information over time, then one ought to satisfy Reflection. There are also associated formal arguments that show that, if one's beliefs about one's current and future selves meet certain criteria, then one is committed by the axioms of probability to satisfy Reflection. The formal arguments, however, rely on an assumption that has no apparent relevance to the intuitive argument: the assumption that one has perfect access to one's beliefs. This paper explains why it is advantageous to replace the perfect access assumption with a self-trust assumption. The self-trust assumption is superior from a formal point of view, since it is formally weaker than the perfect access assumption, and from an intuitive point of view, since it leads to an improved formulation of the intuitive argument