Why Incompetent People Think They’re Competent: The Dunning-Kruger Effect, Explained

When sur­veyed, eighty to nine­ty per­cent of Amer­i­cans con­sid­er them­selves pos­sessed of above-aver­age dri­ving skills. Most of them are, of course, wrong by sta­tis­ti­cal def­i­n­i­tion, but the result itself reveals some­thing impor­tant about human nature. So does anoth­er, less­er-known study that had two groups, one com­posed of pro­fes­sion­al come­di­ans and the oth­er com­posed of aver­age Cor­nell under­grad­u­ates, rank the fun­ni­ness of a set of jokes. It also asked those stu­dents to rank their own abil­i­ty to iden­ti­fy fun­ny jokes. Nat­u­ral­ly, the major­i­ty of them cred­it­ed them­selves with an above-aver­age sense of humor.

Not only that, explains the host of the After Skool video above, “those who did the worst placed them­selves in the 58th per­centile on aver­age. They believed that they were bet­ter than 57 oth­er peo­ple out of 100. Their real score? Twelfth per­centile.” Here we have an exam­ple of the cog­ni­tive bias where­by “peo­ple with a lit­tle bit of knowl­edge or skill in an area believe that they are bet­ter than they are,” now com­mon­ly known as the Dun­ning-Kruger effect. It’s named for social psy­chol­o­gists David Dun­ning and Justin Kruger, who con­duct­ed the afore­men­tioned joke-rank­ing study as well as oth­ers in var­i­ous domains that all sup­port the same basic find­ing: the incom­pe­tent don’t know how incom­pe­tent they are.

“When you’re incom­pe­tent, the skills you need to pro­duce a right answer are exact­ly the skills you need to rec­og­nize what a right answer is,” Dun­ning told Errol Mor­ris in a 2010 inter­view (the first of a five-part series on anosog­nosia, or the inabil­i­ty to rec­og­nize one’s own lack of abil­i­ty). “In log­i­cal rea­son­ing, in par­ent­ing, in man­age­ment, prob­lem solv­ing, the skills you use to pro­duce the right answer are exact­ly the same skills you use to eval­u­ate the answer.” What’s more, “even if you are just the most hon­est, impar­tial per­son that you could be, you would still have a prob­lem — name­ly, when your knowl­edge or exper­tise is imper­fect, you real­ly don’t know it. Left to your own devices, you just don’t know it. We’re not very good at know­ing what we don’t know.”

This brings to mind Don­ald Rums­feld’s much-mocked remark about “unknown unknowns,” which Dun­ning actu­al­ly con­sid­ered “the smartest and most mod­est thing I’ve heard in a year.” (Mor­ris, for his part, would go on to make a doc­u­men­tary about Rums­feld titled The Unknown Known.) But whether you’re the Sec­re­tary of Defense, a cel­e­brat­ed film­mak­er, a Youtu­ber, an essay­ist, or any­thing else, you’ve almost cer­tain­ly been afflict­ed with the Dun­ning-Kruger effect. But if we can make a habit of sub­ject­ing our­selves to brac­ing objec­tive assess­ment, we can — at least, at cer­tain times and cer­tain domains — break free of what T. S. Eliot called the end­less strug­gle to think well of our­selves.

Relat­ed con­tent:

Why Incom­pe­tent Peo­ple Think They’re Amaz­ing: An Ani­mat­ed Les­son from David Dun­ning (of the Famous “Dun­ning-Kruger Effect”)

Bertrand Rus­sell: The Every­day Ben­e­fit of Phi­los­o­phy Is That It Helps You Live with Uncer­tain­ty

John Cleese on How “Stu­pid Peo­ple Have No Idea How Stu­pid They Are” (Oth­er­wise Known as the Dun­ning-Kruger Effect)

24 Com­mon Cog­ni­tive Bias­es: A Visu­al List of the Psy­cho­log­i­cal Sys­tems Errors That Keep Us From Think­ing Ratio­nal­ly

Errol Mor­ris Makes His Ground­break­ing Series First Per­son Free to Watch Online: Binge Watch His Inter­views with Genius­es, Eccentrics, Obses­sives & Oth­er Unusu­al Types

Based in Seoul, Col­in Marshall writes and broad­casts on cities, lan­guage, and cul­ture. His projects include the Sub­stack newslet­ter Books on Cities, the book The State­less City: a Walk through 21st-Cen­tu­ry Los Ange­les and the video series The City in Cin­e­ma. Fol­low him on Twit­ter at @colinmarshall or on Face­book.