No Credences in Active Reasoning: The Argument From Alternative Neglect

ABSTRACT I argue that credences do not participate in an epistemically central kind of mental process—active (i.e., deliberate, person‐level) reasoning. My argument hinges on the empirical finding that human thinkers tend to “neglect alternatives” when deliberately reasoning with uncertainty: in cases where thinkers recognize that their uncertainty is distributed over various possibilities, they tend to engage in downstream reasoning that attends to just one possibility at a time. A model on which thinkers reason with beliefs about probabilities better accounts for the empirical results. I conclude that beliefs play an epistemically important role in human minds that credences do not. Besides motivating a new kind of dualism about belief and credence, my argument additionally suggests a way of characterizing the functional difference between credences and beliefs about probability.