conspiracy theory

A conspiracy theory is an attempt to explain a harmful or tragic event as the result of the secret activities of a small but powerful group. Such explanations reject an official or generally accepted narrative surrounding the event; indeed, such narratives may be seen as further proof of the conspiracy.

Conspiracy theories increase in prevalence in periods of widespread anxiety, suspicion, uncertainty, or hardship, as during wars and economic depressions and in the aftermath of tragic events, such as assassinations and natural disasters. This fact is evidenced in numerous historical conspiracy theories, including those concerning centuries-old Illuminati societies, or groups of elites supposedly manipulating culture and society, as well as in modern theories emerging from the assassination of Pres. John F. Kennedy in 1963, the September 11 attacks of 2001, as well as Pres. Donald Trump’s defeat in the presidential election of 2020.

(Read Steven Pinker’s Britannica entry on conspiracy theories & rationality.)

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Was the Moon Landing Fake?: Why the conspiracy theory

The content of conspiracy theories is emotionally laden, and their alleged discovery can be gratifying. The evidentiary standards for corroborating conspiracy theories are typically weak, and they are usually resistant to falsification. The survivability of conspiracy theories may be aided by psychological biases and by distrust of official sources.

Effects of belief in conspiracy theories

Exposure to media that endorse conspiracies increases belief. For example, there was evidence that the film JFK (1991), directed by Oliver Stone, increased belief in a conspiracy to assassinate Kennedy and decreased belief in the official account that Lee Harvey Oswald acted alone. A further outcome was that people who had seen the film, compared to those who had not, expressed less interest in political participation. Distrust of figures in power thus predicts and is caused by belief in government conspiracies. The later advent of Internet-based social media in the early 2000s and AI-based “deepfake” media in the 2020s—which enabled the production of false but very convincing images, videos, or audios—greatly increased the spread of conspiracy theories. Such deepfake also facilitated dangerous online scams (see cybercrimes).

In the late 20th century researchers investigated an AIDS-related conspiracy theory—the belief that AIDS was created by the U.S. government to kill homosexuals and African Americans—and related attitudes toward condom use. Such research showed that the more strongly African American males believed in the conspiracy, the less favorable their attitudes toward condom use were, and in turn the less likely they were to use condoms. There is also evidence that the conspiracy theory led to distrust of research institutions and was a significant barrier to getting African Americans to participate in AIDS clinical trials.

Such distrust did not develop in a vacuum. Starting in 1932 and continuing for 40 years, the U.S. Public Health Service, working with the Tuskegee Institute, studied the effect of syphilis on 399 African American men. The researchers conducting the Tuskegee syphilis study withheld treatment and allowed more than 100 men to die, despite the discovery of penicillin as a standard cure in 1947. It is clearly worth noting that governments do at least occasionally conspire against their own citizens.

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Explanations of conspiracy theories

American historian Richard Hofstadter (1916–70) explored the emergence of conspiracy theorizing by proposing a consensus view of democracy. Competing groups would represent the interests of individuals, but they would do so within a political system that everyone agreed would frame the bounds of conflict. For Hofstadter, those who felt unable to channel their political interests into representative groups would become alienated from the system. Those people would not accept the statements of opposition parties as representing a fair disagreement; rather, differences in views would be regarded with deep suspicion. Such alienated people would develop a paranoid fear of conspiracy, thus making them vulnerable to charismatic rather than practical and rational leadership. Their vulnerability would thus weaken democracy and potentially lead to totalitarian rule.

In The Paranoid Style in American Politics (1965), Hofstadter proposed that such a threat to democracy is not an individual pathology but instead originates in social conflict that raises fears and anxieties, which in turn leads to status struggles between opposed groups. The resulting conspiracy theorizing derives from a collective sense of threat to one’s group, culture, way of life, and so on.

Extremists at either end of the political spectrum could be expected to develop a paranoid style. On the right, for example, McCarthyism promoted paranoid notions of communist infiltration of American institutions; QAnon, a popular theory among fanatical supporters of U.S. Pres. Donald Trump (2017–21; 2025– ), alleged that prominent Democrats were part of an international cabal of Satan-worshiping pedophiles, cannibals, and child murderers and that Democrats had stolen the presidential election of 2020; and replacement theory claimed that prominent Democrats and other elites were attempting to replace America’s white population with nonwhite immigrants. On the left, the terrorist attacks of September 11, 2001 were thought to have been an “inside job” perpetrated by government and corporate interests; and Jeffrey Epstein (1953–2019), a notorious sex-trafficker of young women and underage girls who committed suicide in prison, was thought to have been murdered at the behest of one or more of his prominent clients, perhaps including Trump himself.

Disproving conspiracies

A 1995 study by American psychologist John McHoskey attempted to provide an explanation for the difficulty of falsifying conspiracy theories. McHoskey gave advocates and opponents of the Kennedy conspiracy a balanced description of arguments for and against a conspiracy to assassinate the president. McHoskey’s prediction was that those who favored and those who opposed the conspiracy theory would both regard the very same statement as evidence in favor of their position. McHoskey believed that this would occur because proponents on both sides engaged in biased assimilation, whereby information that supports one’s position is uncritically accepted, whereas contrary information is scrutinized and discredited. Further, because of attitude polarization, when people encounter ambiguous information, they tend to endorse their original position even more strongly than they did before. This proved to be the case for both advocates and opponents of the Kennedy conspiracy.

Australian philosopher Steve Clarke proposed that conspiratorial thinking is maintained by a fundamental attribution error, whereby people overestimate the importance of dispositions—such as individual motivations or personality traits—while underestimating the importance of situational factors—such as random events and social norms—in explaining the behavior of others. Clarke observed that this error is typical of conspiratorial thinking. People maintain adherence to their conspiratorial beliefs because to dispense with the conspiracy would be to discount human motives in events.

Clarke further suggested that the ultimate reason people make the fundamental attribution error is because they have evolved to do so. Humans evolved in tightly knit groups where understanding the motives of others was critical for the detection of malevolent intentions. The cost of making an error in identifying others’ insidious motives was small relative to the cost of not identifying such motives at all. As a result, people became psychologically attuned to discount situational factors over dispositional factors in explaining others’ behavior.