How Much Do Experts Really Know? As Knowledge Increases, so do Overclaims of What is Actually Known

You Don't Know as Much as You Think: False Expertise is the title of an article by Jessica Schmerler at Scientific American reporting on a study by researchers at Cornell University and Tulane University published in Psychological Science.

The study found that people with a self-perceived "knowledge" of a subject tend to "overclaim" their actual knowledge in that subject. The more they know or think to know, the more they overclaim what they actually do know.

That research explains a phenomenon we have encountered repeatedly in our own research work, which is the vast overclaiming of knowledge in archaeological disciplines and related historical fields by so-called mainstream "experts". After all, who can check them for things that happened in the past?

One can see this overclaiming demonstrated particularly in so-called historical TV "documentaries", where much of the material presented often consists of nothing more than pure guesses and unsubstantiated suppositions and "overclaims" of knowledge. Things are presented as if they were "true", whereas much of what is communicated is simply the fantasy of the experts.

Given the findings of the Cornell study, one might conclude that this phenomenon of overclaiming applies to all fields of human knowledge and activity. We see this particularly among "Presidential candidates".

The "free" Abstract of the study by Stav Atir, Emily Rosenzweig and David Dunning is titled "When Knowledge Knows No Bounds: Self-Perceived Expertise Predicts Claims of Impossible Knowledge" and is found at Sage Journals at http://pss.sagepub.com/content/early/2015/07/14/0956797615588195.abstract

The price to download the full article ($35) seems to be "anti-knowledge". The next step from a study of "overclaiming" might be a study of "overpricing", and whether the same human psychology is at work in both cases.