A recent study out of Cornell University, published on June 25, 2025, challenges what we thought we knew about conspiracy theorists. Turns out, it’s not all about narcissism or the need to feel special. What really seems to drive these beliefs is something much simpler: people overestimating how good their judgment is, and wrongly assuming everyone else agrees with them (Neuroscience News, 2025).
How the Study Was Designed
Researchers ran eight separate experiments with over 4,100 adults across the U.S. Participants took part in classic cognitive tasks—things like recognising patterns and estimating numbers, alongside surveys that asked how much they believed in popular but debunked conspiracy theories, like the moon landing being faked or Princess Diana’s death being staged. However, the group’s addition of four specially designed “overconfidence tests” was the interesting part. For these, participants had to guess how well they would perform on tasks that were almost impossible to do right. The greater the gap between their perceived and actual performance, the greater their overconfidence.
Read More: Conspiracy Theories: Understanding Its Appeal and Social Impact
The Confidence Mismatch
The results? Pretty striking. People who believed in conspiracy theories consistently thought they did way better than they did. It wasn’t just that they had the wrong facts—they had an inflated sense of how good they were at figuring out what’s true in the first place.
Thinking Everyone Else Agrees
A further noteworthy discovery was how ridiculously wrong their public opinion forecast was. Even though they were a very small minority, conspiracy theorists thought that about 93% of the study participants held similar opinions. They overlooked opposing arguments or fact-checks in favour of sticking to their opinions as a result of this “false consensus.”
It’s Not About Personality After All
Earlier explanations for conspiracy thinking often pointed to traits like narcissism, a love of being different, or deep mistrust of authority. But this study flips the script. It suggests the real culprit might be a basic mental blind spot—thinking you’re more right than you actually are and assuming others must see it your way too.
Measuring the Unmeasurable
Since people aren’t very good at evaluating their abilities, it can be difficult to measure overconfidence. In order to prevent this, the researchers implemented tasks that lacked a clear conclusion, such as imagining what a highly blurred image displayed. Someone turned out to be overconfident if they claimed to have nailed it.
What This Means for Public Conversations
In today’s complexly complicated world, this pattern has serious consequences. When people think a lot of other people agree with them, they are more likely to spread incorrect information and disregard corrections. Presenting information that is more precise is only a single component of addressing false beliefs; another is facing that misplaced confidence.
Read More: Overconfidence vs. Underestimation: The Psychological Trap of the Dunning-Kruger Effect
Can We Teach People to Be Less Certain?
According to the researchers, providing accurate information may not be as crucial as assisting people in becoming more conscious of their mental boundaries, a process known as metacognitive training. Conspiracy theories may be less likely to spread if people are encouraged to consider how much they know and to hear different points of view.
The Bigger Picture
By showing that overconfidence, not just personality quirks, can lead people down the conspiracy rabbit hole, this study offers a new way to think about the problem. If we can address this cognitive bias at its root, we might finally make some progress in tackling the misinformation epidemic.
FAQs
1. What is the main reason some people believe in conspiracy theories?
Recent research suggests that overconfidence in one’s own judgment—rather than narcissism or uniqueness-seeking—is a major driver. These individuals tend to overestimate both their knowledge and how widely their beliefs are shared.
2. How did researchers measure overconfidence in the study?
Participants were asked to complete difficult or ambiguous cognitive tasks, then estimate how well they performed. A large gap between perceived and actual performance indicated trait overconfidence.
3. Do conspiracy believers know they’re in the minority?
No. On average, conspiracy believers believed that 93% of others agreed with them, even though their views were statistically fringe. This is known as the false consensus effect.
4. Can correcting misinformation help change these beliefs?
Not easily. Because these individuals are highly confident and believe others agree with them, corrective facts alone are often ineffective. The study suggests that promoting metacognitive awareness may be more impactful.
5. Is overconfidence linked to low intelligence or education?
Not necessarily. Overconfidence is a cognitive bias, not a reflection of intelligence. Even highly educated individuals can fall prey to it if they lack insight into their own knowledge limits.
6. What can be done to reduce belief in conspiracy theories?
Encouraging mental humility, teaching people to question their certainty, and correcting their assumptions about public consensus are promising strategies for countering conspiracy thinking.
References +
Pennycook, G., Binnendyk, J., & Rand, D. G. (2025, May 24). Overconfidently conspiratorial: Conspiracy believers are dispositionally overconfident and massively overestimate how much others agree with them. Personality and Social Psychology Bulletin. Advance online publication. https://doi.org/10.1177/01461672251338358
Binnendyk, J., & Pennycook, G. (2024). Individual differences in overconfidence: A new measurement approach. Judgment and Decision Making, 19, Article e28. https://doi.org/10.1017/jdm.2024.22
Moore, D. A., & Healy, P. J. (2008). The trouble with overconfidence. Psychological Review, 115(2), 502–517. https://doi.org/10.1037/0033-295X.115.2.502
Ross, L., Greene, D., & House, P. (1977). The false consensus effect: An egocentric bias in social perception and attribution processes. Journal of Experimental Social Psychology, 13(3), 279–301. https://doi.org/10.1016/0022-1031(77)90049-X
Cornell University. (2025, June 25). Conspiracy theorists are unaware that their beliefs are on the fringe. Cornell Chronicle. Retrieved June 27, 2025, from Cornell University News Service
