Optimizing Individual and Collective Reliability: A Puzzle

Many epistemologists have argued that there is some degree of independence between individual and collective reliability (e.g., Kitcher 1990; Mayo-Wilson, Zollman, and Danks 2011; Dunn 2018). The question, then, is: To what extent are the two independent of each other? And in which contexts do they come apart? In this paper, I present a new case confirming the independence between individual and collective reliability optimization. I argue that, in voting groups, optimizing individual reliability can conflict with optimizing collective reliability. This can happen even if various conditions are held constant, such as: the evidence jurors have access to, the voting system, the number of jurors, some independence conditions between voters, and so forth. This observation matters in many active debates on, e.g., epistemic dilemmas, the wisdom of crowds, independence theses, epistemic democracy, and the division of epistemic labour.