"A-ha, I hadn’t thought of that": the Bayesian Problem of Awareness Growth
Vasily Romanovskiy

Abstract:
The Bayesian Problem of Awareness Growth is Bayesianism’s apparent inability to account for the way our beliefs change in situations of awareness growth, those “a-ha, I hadn’t thought of that” moments familiar to all of us. This thesis is concerned with attempts to modify Bayesianism so as to solve this problem and its chief contribution is threefold. First, it clarifies the Bayesian Problem of Awareness Growth by distinguishing two different versions of the problem, arguing against one of these versions on the grounds that it is at odds with the normative ambitions of Bayesianism and finally, delineating for whom and when my preferred version of the Bayesian Problem of Awareness Growth is a problem. The remaining two-part contribution is a contribution to two key debates around the Bayesian Problem of Awareness Growth. Some argue that a “none-of-the-above” option should be included to make space for future awareness growth. As far as the “none-of-the-above” option is concerned, I argue that if one wants to include such an option there is a way to proceed but arguments for always including such an option fail. I then turn to a putative norm that governs a change in beliefs in light of awareness growth: Reverse Bayesianism. I argue that it is not an exceptionless norm of rationality in the case of awareness growth, however, even when it fails it can be used as part of a general procedure for revising credences in light of awareness growth.