Abstract

One of the major problems in formal epistemology is the difficulty of combining probabilistic and dichotomous (all-or-nothing) beliefs in one and the same formal framework. In this presentation I will begin with an epistemological discussion on how they should be combined, based on considerations of optimal use of our limited cognitive resources. This will be followed by a presentation of a formal model that serves as a proof of concept that the two types of beliefs can be adequately represented in one and the same formal framework. In this formal model, infinitesimal probabilities are used as carriers of memories of beliefs that have been given up. Empirical full beliefs can be given up, and their pattern of change constitutes a credible system of all-or-nothing belief change.