Psychologists usually attribute belief in conspiracy theories to a number of psychopathological conditions such as paranoia, schizotypy, narcissism, and insecure attachment,[9] or to a form of cognitive bias called "illusory pattern perception".[24][25] It has also been linked with the so-called Dark triad personality types, whose common feature is lack of empathy.[26] However, a 2020 review article found that most cognitive scientists view conspiracy theorizing as typically nonpathological, given that unfounded belief in conspiracy is common across both historical and contemporary cultures, and may arise from innate human tendencies towards gossip, group cohesion, and religion.[9] One historical review of conspiracy theories concluded that "Evidence suggests that the aversive feelings that people experience when in crisis—fear, uncertainty, and the feeling of being out of control—stimulate a motivation to make sense of the situation, increasing the likelihood of perceiving conspiracies in social situations."[27]
Historically, conspiracy theories have been closely linked to prejudice, propaganda, witch hunts, wars, and genocides.[12][28][29][30][31] They are often strongly believed by the perpetrators of terrorist attacks, and were used as justification by Timothy McVeigh and Anders Breivik, as well as by governments such as Nazi Germany, the Soviet Union,[28] and Turkey.[32] AIDS denialism by the government of South Africa, motivated by conspiracy theories, caused an estimated 330,000 deaths from AIDS.[33][34][35] QAnon and denialism about the 2020 United States presidential election results led to the January 6 United States Capitol attack,[36][37][38] and belief in conspiracy theories about genetically modified foods led the government of Zambia to reject food aid during a famine,[29] at a time when three million people in the country were suffering from hunger.[39] Conspiracy theories are a significant obstacle to improvements in public health,[29][40] encouraging opposition to such public health measures as vaccination and water fluoridation. They have been linked to outbreaks of vaccine-preventable diseases.[29][33][40][41] Other effects of conspiracy theories include reduced trust in scientific evidence,[12][29][42] radicalization and ideological reinforcement of extremist groups,[28][43] and negative consequences for the economy.[28]
