Belief in conspiracy theories is often attributed to some form of motivated reasoning: People want to believe a conspiracy because it reinforces their worldview, for example, or doing so meets some deep psychological need, like wanting to feel unique. However, it might also be driven by overconfidence in their own cognitive abilities, according to a paper published in the Personality and Social Psychology Bulletin. The authors were surprised to discover that not only are conspiracy theorists overconfident, they also don't realize their beliefs are on the fringe, massively overestimating by as much as a factor of four how much other people agree with them.
"I was expecting the overconfidence finding," co-author Gordon Pennycook, a psychologist at Cornell University, told Ars. "If you've talked to someone who believes conspiracies, it's self-evident. I did not expect them to be so ready to state that people agree with them. I thought that they would overestimate, but I didn't think that there'd be such a strong sense that they are in the majority. It might be one of the biggest false consensus effects that's been observed."
In 2015, Pennycook made headlines when he co-authored a paper demonstrating how certain people interpret "pseudo-profound bullshit" as deep observations. Pennycook et al. were interested in identifying individual differences between those who are susceptible to pseudo-profound BS and those who are not and thus looked at conspiracy beliefs, their degree of analytical thinking, religious beliefs, and so forth.
