Conditionalization and total knowledge

This paper employs epistemic logic to investigate the philosophical foundations of Bayesian updating in belief revision. By Bayesian updating, we understand the tenet that an agent's degrees of belief--assumed to be encoded as a probability distribution--should be revised by conditionalization on the agent's total knowledge up to that time. A familiar argument, based on the construction of a diachronic Dutch book, purports to show that Bayesian updating is the only rational belief-revision policy. We investigate the conditions under which of the premises of this argument might be satisfied. Specifically, we consider the case of an artificial agent whose language (of thought) features a modal operator TK, where TK has the interpretation "My total knowledge is ". We show that every proposition of the form TK is epistemically categorical: it determines, for every proposition in the agent's language, whether the agent knows that . We argue that, for certain artif...

• Type: Journal
• Year: 2008
• Where: JANCL
• Authors: Ian Pratt-Hartmann
• Keywords: Diachronic Dutch Book, JANCL 2008, Logic, Total Knowledge