Peer disagreement and higher‐order evidence

Abstract

Peer disagreement occurs when individuals with identical evidence and similar cognitive reliability reach conflicting conclusions. The Equal Weight View, which requires parties to split the difference between their views regardless of the first-order evidence’s actual support, is fundamentally flawed. By treating the distribution of opinion as the sole determinant of rationality, this view permits irrational beliefs to bootstrap themselves into reasonableness and ignores the epistemic asymmetry between a peer who evaluates evidence correctly and one who does not. In its place, the Total Evidence View posits that the rational response to disagreement depends on the totality of considerations, comprising both original first-order evidence and the higher-order evidence provided by the opinions of others. While the discovery of disagreement typically necessitates some revision of confidence because it serves as evidence of fallibility, it does not render the original evidence irrelevant. The degree of justified revision is thus a function of the relative weight of these two types of evidence. In scenarios with extensive first-order data, the individual who correctly evaluates that data maintains a justified advantage; conversely, as the number of independent peers increases, higher-order psychological evidence can eventually swamp first-order considerations into virtual insignificance. – AI-generated abstract.