You know those people who claim to know everything, commonly known as “know-it-alls”? Well next time you encounter one you can rest assured that most of what they claim to know is actually false. A new study from Cornell University finds that those who “overclaim”, or think they know everything about a particular topic, are more likely to pretent knowledge of completely false information.
According to the Israeli psychological scientist Stav Atir, who conducted the study, “Our work suggests that the seemingly straightforward task of judging one’s knowledge may not be so simple, particularly for individuals who believe they have a relatively high level of knowledge to begin with,” he said in a statement.
For know-it-alls, false facts are hard to spot
The claim seems to be a logical one, but how do you go about testing one’s purported knowledge against their actual knowledge and expertise?
To find out why people make these spurious claims, Atir and colleagues from Cornell and Tulane Universities designed a series of experiments to test out people’s self-perceived knowledge, compared to their actual expertise.
One hundred participants were asked to rate their general knowledge of personal finance, as well as their knowledge of 15 specific financial terms. Most of the terms on the list were real (for example, Roth IRA, inflation, home equity), but the researchers also included three made-up terms (pre-rated stocks, fixed-rate deduction, annualized credit).
As expected, people who saw themselves as financial wizards were most likely to claim expertise of the bogus financial terms that were added into the mix.
“The more people believed they knew about finances in general, the more likely they were to overclaim knowledge of the fictitious financial terms,” Atir said. “The same pattern emerged for other domains, including biology, literature, philosophy, and geography.”
“For instance,” Atir explains “people’s assessment of how much they know about a particular biological term will depend in part on how much they think they know about biology in general.”
Catching overclaimers off guard
In another experiment, the researchers warned one set of 49 participants ahead of time that some of the terms on a list would be made up. However, even after receiving the warning, the self-proclaimed experts were more likely to confidently claim familiarity with fake biological terms, such as “meta toxins” and “bio-sexual.”
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To confirm that people’s self-perceived expertise was driving their overclaiming, the research team manipulated participants’ sense of knowledge mastery through a geography quiz. Participants were randomly assigned to complete either an easy quiz on iconic US cities, a difficult quiz on very obscure places, or no quiz. Those participants who had completed the easy quiz felt like experts, and reported that they were more knowledgeable about geography in general than those individuals in the other two groups.
The participants then rated their familiarity with a list of real—and a few completely fake—US cities.
In all three conditions people recognized the real locations, such as Philadelphia and the National Mall. Ironically, those people who had taken the easy quiz, and concluded they were more knowledgeable about US geography, were more likely than the other two groups to claim they were knowledgeable about non-existent locations, such as Cashmere, Oregon.
Know-it-alls risk the danger of knowing less
The research team warns that a tendency to overclaim, especially in self-perceived experts, may actually discourage individuals from educating themselves in precisely those areas in which they consider themselves knowledgeable—leading to potentially disastrous outcomes.
For example, failure to recognize or admit one’s knowledge gaps in the realm of finance or medicine could easily lead to uninformed decisions with devastating consequences for individuals.
“Continuing to explore when and why individuals overclaim may prove important in battling that great menace—not ignorance, but the illusion of knowledge,” the research team concludes.
The research, conducted by lead researcher Stav Atir of Cornell University, together with David Dunning and Emily Rosenzweig of Tulane University, was published in the Association for Psychological Science’s journal “Psychological Science”.