The Equal Weight View, Agreement, and Commutativity

Abstract

This paper investigates Elga’s (2007) Equal Weight View (EWV) and its consequences when understood as a view requiring epistemic peers to ‘split the difference’ following disagreement. The traditional disagreement debate is extended to consider the epistemic significance of agreement and diachronic applications of the EWV. It is shown that a weighted averaging approach to belief revision is inconsistent with peer agreement raising confidence; a result inconsistent with other conciliatory positions. Diachronic applications of the EWV can result in an agent’s credence varying as a function of contingent facts about the order in which epistemic peers and therefore higher-order evidence are encountered; a result which I argue is unacceptable for the EWV. I conclude that understanding the EWV as requiring ‘weighted averaging’ is often inconsistent with the spirit of the view and we should seek an alternative.