Vigilant conservatism in evaluating communicated information

In the absence of other information, people put more weight on their own opinion than on the opinion of others: they are conservative. Several proximal mechanisms have been suggested to account for this finding. One of these mechanisms is that people cannot access reasons for other people’s opinions, but they can access the reasons for their own opinions—whether they are the actual reasons that led them to hold the opinions (rational access to reasons), or post-hoc constructions (biased access to reasons). In four experiments, participants were asked to provide an opinion, and then faced with another participant’s opinion and asked if they wanted to revise their initial opinion. Some questions were manipulated so that the advice participants were receiving was in fact their own opinion, while what they thought was their own opinion was in fact not. In all experiments, the participants were consistently biased towards what they thought was their own opinion, showing that conservativeness cannot be explained by rational access to reasons, which should have favored the advice. One experiment revealed that conservativeness was not decreased under time pressure, suggesting that biased access to reasons is an unlikely explanation for conservativeness. The experiments also suggest that repetition plays a role in advice taking, with repeated opinions being granted more weight than non-fluent opinions. Our results are not consistent with any of the established proximal explanations for conservatism. Instead, we suggest an ultimate explanation—vigilant conservatism—that sees conservatism as adaptive since receivers should be wary of senders’ interests, as they rarely perfectly converge with theirs.