Mixed

A recent study investigated the relationship between specific beliefs - particularly belief in conspiracy theories and religiosity - and susceptibility to conjunction errors (CEs) in different subject areas. This involved 500 participants being presented with short scenarios in three different domains: 'coronavirus conspiracies', 'miraculous healings' and a control condition that did not address specific beliefs. Each scenario consisted of a statement about a single event and another statement describing two events occurring simultaneously. Participants were asked to rate the likelihood of each described event occurring.

The results of this study revealed a clear link between the participants' specific beliefs and their tendency to make conjunction errors, but only in the thematically relevant areas. For example, belief in coronavirus conspiracy theories correlated significantly with a higher number of CEs in the area of coronavirus scenarios. Similarly, participants' general religiosity was exclusively associated with CEs in the miraculous healing scenarios. Interestingly, there was no significant association between the beliefs studied and conjunction errors in the control condition, suggesting that susceptibility to CEs in certain contexts is influenced by individuals' specific beliefs.

These findings shed new light on the understanding of the cognitive processes underlying the evaluation of probabilities in different contexts. They suggest that susceptibility to conjunction fallacies is not just a general tendency, but is also modulated by personal beliefs and thematic context. This underscores the importance of understanding how individual differences in beliefs can influence cognitive processing in specific situations. The results of this study thus contribute to a more nuanced understanding of the factors that influence our judgment and decision making, particularly with regard to assessing the likelihood of events in areas close to our deepest beliefs.