Proceedings of the Annual Meeting of the Cognitive Science Society

As we navigate our information-rich world, we frequently interpret and integrate testimony from external sources (friends, teachers, books, internet articles, etc.) – deciding which pieces of information to believe, and which to discard. One cue to a statement’s trustworthiness is whether it comes from a consensus (i.e., when a majority of people agree). But what counts as consensus? When presented with a set of agreeing sources, do we evaluate the quality of consensus – for example, asking whether each source arrived at their conclusion by independent means? In a first experiment, we demonstrate that individuals are insensitive to the quality of a consensus, and are equally confident in conclusions drawn from a ‘true’ consensus (i.e., one derived from many primary sources) and those drawn from a ‘false’ consensus (i.e., one derived from many secondary sources but only a single primary source). In a second experiment, we find that this continues to be true even when the expertise of the secondary sources is minimized. Together, our experiments provide converging evidence that people do not properly discount (or discount at all) information from a ‘false’ consensus.