Paul de Font-Reaulx (Oxford): 'Evidentialism and Why There Ain't No Such Thing as A Computationally Free Lunch'
Chair: Sebastian Liu
In much of contemporary epistemology it is assumed that we ought to believe what our evidence supports. One aspect of this suggestion has however been neglected, namely that it ignores the cognitive costs of inferring what our evidence supports. In this paper I argue that when those costs are high but the evidence decisive, this gives rise to deeply counterintuitive consequences. This is brought out most clearly by cases of mathematical evidence. I claim that ignoring the costs of thinking leaves us with an implausible theory of justified belief that jars with scientific practice. To accommodate the costs of thinking I suggest that we introduce a separate notion of reasonable belief, satisfied when one makes the most of one‘s computational resources. Finally I suggest that the explicit introduction of reasonable belief in our conceptual toolbox can dissolve otherwise intractable debates in contemporary epistemology, such as those regarding peer-disagreement.