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Daniel Kahneman, PhD, is one of the world’s preeminent psychologists and was awarded the Nobel Prize in Economics in 2002. Author of the best-selling book, Thinking, Fast and Slow, his research to better understand cognitive biases is where he has been most impactful. Among the many cognitive biases to which human beings are susceptible, Kahneman has been quoted as saying that he believes the most damaging bias is overconfidence. The tendency to believe that we know more than we do leads people to act based on opinion rather than objective or factual evidence, and can have costly consequences.
A number of scientific papers have been published this year on the topic of overconfidence. One of these, published in PNAS (Proceedings of the National Academy of Sciences), found that approximately three quarters of US adults overestimate their ability to determine which news headlines are legitimate or false. These overconfident individuals are more likely to search untrustworthy websites and to subsequently share on social media what they found. In other words, those least able to detect misinformation or disinformation are most prone to forwarding such content.
An article published in the Journal of Experimental Psychology: General reports the results of six studies aimed at examining the role of social transmission in the development of overconfidence. In other words, does the overconfidence of others affect one’s own propensity to be overconfident? The answer is yes. Social learning plays a role in the overconfidence of those within a group. The tendency to believe what others in one’s in-group believe, even when that information is unwarranted or false, is quite robust. This influence doesn’t have to be direct from one person to another; the process can occur in indirect relationships, such as those found on social media. Furthermore, the social transmission of overconfidence occurs outside of awareness. Groups in which overconfidence is epidemic do not typically contain individuals who are able to be unbiased or to correct misinformation within the group.
Another article published this year in the International Journal of Psychology examined what happens when individuals are presented with corrected information after having received misinformation. While corrections were inclined to neutralize positive misinformation, negative misinformation tended to persist in spite of corrections.
The results of these studies are not surprising for those who lament how misinformation has and continues to undermine public health efforts to thwart the COVID-19 pandemic. Overconfidence can be like a virus within a group. Adding to susceptibility for spread of the “overconfidence virus” is the confirmation bias — the tendency to seek information that is consistent with what one already believes. One of the most troubling types of viral overconfidence is the distrust of science. While science has its limitations, it aims to minimize the role of subjectivity in explaining phenomena.
As noted earlier, it is very challenging to correct overconfidence in misinformation. Often what is required is some personal experience that is dissonant with one’s belief (e.g., getting seriously ill with COVID-19 can counteract the belief that “COVID is no worse than a cold”). Such experiences among others in one’s in-group can be the beginning of the social transmission of alternative, more accurate information, although correcting misinformation is an uphill challenge.
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