  In previous work ("Knowledge from Probability", TARK 2021) we develop a
question-relative, probabilistic account of belief. On this account, what
someone believes relative to a given question is (i) closed under entailment,
(ii) sufficiently probable given their evidence, and (iii) sensitive to the
relative probabilities of the answers to the question. Here we explore the
implications of this account for the dynamics of belief. We show that the
principles it validates are much weaker than those of orthodox theories of
belief revision like AGM, but still stronger than those valid according to the
popular Lockean theory of belief, which equates belief with high subjective
probability. We then consider a restricted class of models, suitable for many
but not all applications, and identify some further natural principles valid on
this class. We conclude by arguing that the present framework compares
favorably to the rival probabilistic accounts of belief developed by Leitgeb
and by Lin and Kelly.
