Few psychological rules have as high a public profile as the Dunning-Kruger effect. Way back in 1999, yes, 26 years ago, David Dunning and Justin Kruger showed that the people who were least competent at a given task were also the most confident in their abilities. Meanwhile, the most skilled are the most unsure.
In those 26 years since Dunning and Kruger published their landmark paper, scientists have debated the details of the findings. But the public has run with it. It’s not hard to see why. A theory that states the dumbest among are often the loudest and most overconfident seems to explain so much about modern life.
Plus, it's a handy grenade to throw in a social-media fight. Search “Dunning-Kruger Effect” online and you’ll find huge numbers of people labeling those they disagree as obvious cases of the effect in action.
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