In this post, I (Lisa Bortolotti) discuss some of the similarities and differences between conspiracy beliefs and delusions—this is the topic of a paper co-authored with Anna Ichino and Matteo Mameli for Reti, Saperi, Linguaggi.
Surface featuresBoth conspiracy beliefs and delusions of persecution involve attributing evil intentions or responsibility for adverse events to an individual or a group that the person does not trust. Conspiracy beliefs, but not delusions, are typically developed as an alternative to an official, authoritative version of the events (Ichino and Räikkä 2020). Both types of belief are regarded as implausible by those who do not share them.
In terms of being supported by evidence, there is considerable variation. Generally, conspiracy beliefs and delusions are poorly supported by the available evidence. However, the suspiciousness or mistrust may be partially explained by adverse experiences in a person’s life (Gunn and Bortolotti 2018) or by the marginalization of the minority group to which the person belongs (Levy 2019).
In terms of being responsive to evidence, both conspiracy beliefs and delusions are characterized as unshakeable (Shearman 2018): people acknowledge challenges and respond to them but are not open to abandoning or revising their beliefs. Often the belief becomes more elaborated and entrenched when it is challenged (Sunstein and Vermeule 2009).
Causal historyBoth types of belief have been explained by predictive processing theories and two-factor models of belief formation. For predictive processing theories (Reed et al. 2020), conspiracy beliefs and delusions of persecution are inferences under uncertainty, a response to situations characterized by ambiguity or threat.
For two-factor theories (Pierre 2020), conspiracy beliefs and delusions are explained by two factors: factor one is usually an anomalous experience in the case of delusions and epistemic mistrust in the case of conspiracy beliefs; factor two lies in cognitive biases and motivated reasoning for both types of belief.
Neither account necessarily implies that a cognitive dysfunction is responsible for the adoption of conspiracy beliefs or delusions.
Downstream effectsConspiracy beliefs are shared and tend to strengthen group belonging and affiliation, whereas delusions are typically idiosyncratic and deeply isolating. So, whereas delusions of persecution can be extremely distressing and disrupt a person’s life, the acceptance of a conspiracy theory is generally comforting.
But not all persecutory delusions are disruptive, and some can be a source of relief or empowerment (Ritunnano et al. 2021). Moreover, some conspiracy beliefs result in individual and collective harms (Douglas et al. 2019).
ConclusionsIt is difficult to draw general conclusions from the comparison between conspiracy beliefs and delusions.
One worry is that highlighting the similarities may lead to an unwarranted pathologization of people who endorse conspiracy beliefs. It is undesirable to extend further the already regrettable stigma commonly associated with having a mental illness for the purposes of excluding dissenting voices from public debate and limiting some citizens’ participation in collective discussion and deliberation.