We often evaluate belief-forming processes, agents, or entire belief states for reliability. This is normally done with the assumption that beliefs are all-or-nothing. How does such evaluation go when we’re considering beliefs that come in degrees? I consider a natural answer to this question that focuses on the degree of truth-possession had by a set of beliefs. I argue that this natural proposal is inadequate, but for an interesting reason. When we are dealing with all-or-nothing belief, high reliability leads to high levels of truth-possession. However, when it comes to degrees of belief, reliability and truth-possession part ways. The natural answer thus fails to be a good way to evaluate degrees of belief for reliability. I propose and develop an alternative method based on the notion of calibration, suggested by Frank Ramsey, which does not have this problem and consider why we should care about such assessments of reliability even if they are not tied directly to truth-possession.
KeywordsGoldman Reliabilism Reliability Scoring rules Credences Degrees of belief Bayesian Calibration Refinement Power
Earlier versions of this paper were given at the Fall 2011 Meeting of the Indiana Philosophical Association, the 2012 Central APA, and at Western Michigan University. Thanks to all participants there. Thanks especially to Erik Wielenberg, Jennifer Lackey, Lara Buchak, Chris Meacham, James Joyce, Ethan Brauer, and anonymous reviewers for Philosophical Studies for very helpful comments.
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