A recent study published in the journal Social Psychological and Personality Science explores how individuals assess the plausibility of conspiracy theories. The research reveals that a suspicious mindset is strongly linked to perceiving implausible conspiracy theories as plausible, while cognitive skills and rational thinking dispositions are negatively associated with finding such theories credible.
The motivation behind the study stems from the need to understand the role of conspiracy theories in democratic societies. Democracies thrive on the participation of informed and critical citizens. Conspiracy theories typically attribute significant events to secretive and malevolent actors. While many conspiracy theories are baseless and reflect more on the believers’ motivations than on actual evidence, others — such as the Watergate scandal — have proven to be true.
However, the psychological underpinnings that differentiate judgments of plausible versus implausible conspiracy theories have not been thoroughly investigated. The new study aimed to fill that gap by examining the role of general suspicion (referred to as conspiracy mentality), cognitive skills, and critical thinking in the plausibility judgments of conspiracy theories.
“In science and society, conspiracy theories are often considered untrue. However, there are cases in which the assumption that malevolent actors secretly caused an event may actually be quite plausible,” said study author Marius Frenken, a research associate at the University of Mainz.
“Determining whether a theory is plausible or implausible can be a difficult task and there is a fine line between being uncritical and being overly skeptical. Therefore, we were interested in understanding the psychological factors relevant to plausibility judgments about conspiracy theories. This is important because critical, fact-based citizens are essential for vibrant democracies.”
To examine the psychological correlates of plausibility judgments regarding conspiracy theories, the researchers first conducted a pretest among 122 German students to select conspiracy theories based on their perceived plausibility. From an initial pool of 11 theories, six were chosen — three deemed plausible and three implausible — based on the students’ ratings. The theories were designed to be fictitious to avoid biases stemming from pre-existing knowledge.
For example, one of the implausible conspiracy theories alleged: “The Lumarian government, facing declining support, staged a false flag terrorist attack on a crowded train station with the help of its intelligence service. As the election approached, tensions rose and the government used fear to rally the population against a perceived terrorist threat in order to maintain its grip on power.”
In contrast, this was deemed to be a plausible conspiracy theory: “A cabal of wealthy individuals, including media mogul Robin Parker and investment banker Maria Rodriguez, manipulate the stock market for their own financial gain. This includes insider trading, spreading false rumors to influence share prices, or colluding with other investors to artificially inflate or deflate the value of certain shares.”
The researchers then recruited a sample of 271 participants from the United Kingdom and the United States through the online platform Prolific. The sample was composed of English native speakers with an average age of around 41 years. The participants rated the plausibility of the six selected conspiracy theories on a scale from 1 (very unlikely) to 7 (very likely).
In addition to these ratings, participants completed several psychological measures. These included a 12-item scale to assess their conspiracy mentality, a modified Cognitive Reflection Task and the Bullshit Receptivity Scale to measure cognitive skills, and an 11-item critical thinking disposition scale.
Frenken and his colleagues found a significant association between conspiracy mentality and the perceived plausibility of both plausible and implausible conspiracy theories. However, this association was markedly stronger for implausible conspiracy theories.
“We would have expected that the general skeptical attitude of conspiracy-minded individuals would apply equally to both plausible and implausible conspiracy theories,” Frenken told PsyPost. “However, it appears to be particularly important for implausible theories. Conversely, this suggests that individuals who are less prone to conspiracy thinking may not generally dismiss the possibility that conspiracies can exist.”
Additionally, the the researchers found that cognitive skills were negatively associated with the plausibility judgments of implausible conspiracy theories. In other words, individuals with higher cognitive skills were less likely to find implausible conspiracy theories credible. But there were no significant correlations between cognitive skills and the plausibility judgments of plausible conspiracy theories, highlighting a specific cognitive bias towards believing implausible theories among those with lower cognitive skills.
Interestingly, the disposition to engage in critical thinking did not show a significant correlation with the plausibility judgments of conspiracy theories. This finding suggests that the self-reported tendency to engage in systematic questioning and rational evaluation may not be a decisive factor in distinguishing between plausible and implausible conspiracy theories.
In a second study, the researchers aimed to validate and extend their findings by experimentally manipulating the plausibility of conspiracy theories. This study involved 292 participants from the United Kingdom and the United States, also recruited through Prolific. The researchers used a belief-updating paradigm to see how additional information impacts the perceived plausibility of various explanations, including conspiracy theories.
Participants first read an introductory sentence about a fictitious event and one of four potential explanations for each event: a plausible option, two initially plausible lures that were later discredited, and one absurd explanation. The participants then received additional information and re-evaluated the plausibility of the explanations. Finally, participants received a final piece of information indicating the most plausible explanation and rated the explanations again.
The researchers observed that conspiracy mentality continued to predict the plausibility judgments of both plausible and implausible conspiracy theories across all stages of information provision. However, as in the first study, the influence of conspiracy mentality was notably stronger for implausible conspiracy theories, even after participants were provided with additional information that should have discredited these theories. This indicates a resistance to disconfirming evidence among individuals with a high conspiracy mentality.
Furthermore, cognitive skills continued to play a significant role in plausibility judgments. Higher cognitive skills were associated with a lower likelihood of endorsing implausible conspiracy theories after the provision of additional information.
“The psychological bases for judging plausible and implausible conspiracy theories are quite different,” Frenken explained. “Implausible conspiracy theories tend to appeal more to people who rely on intuition rather than rational or reflective thinking.”
“This is also true of people with the suspicious worldview known as conspiracy mentality, so thinking in terms of conspiracy theories in general may not be helpful in making plausibility judgments about them. Psychological factors commonly associated with conspiracy beliefs in scientific studies are less relevant to plausible conspiracy theories.”
As with all research, however, there are some caveats to consider.
“It is important to note that the generalizability of our findings is limited to populations in liberal Western democracies,” Frenken noted. “It would be interesting to investigate whether this pattern holds true in countries with higher levels of corruption, where heightened suspicion is more closely aligned with actual covert activities behind the scenes.”
“The main difficulty in such a study is categorizing conspiracy theories objectively as plausible or implausible. Therefore, we conducted studies in fictional settings and experimentally manipulated the plausibility of conspiracy explanations by varying their alignment with tangible evidence.”
The study, ““Just Because It’s a Conspiracy Theory Doesn’t Mean They’re Not Out to Get You”: Differentiating the Correlates of Judgments of Plausible Versus Implausible Conspiracy Theories“, was authored by Marius Frenken, Annika Reusch, and Roland Imhoff.