"Long before it's in the papers"
January 27, 2015


Self-delusion a winning survival strategy, study suggests

Sept. 15, 2011
Courtesy of the University of Edinburgh
and World Science staff

Har­bor­ing a mis­tak­enly in­flat­ed be­lief that we can easily meet chal­lenges or win con­flicts is ac­tu­ally good for us, new re­sults from sim­ula­t­ions sug­gest.

Pub­lished in the re­search jour­nal Na­ture Sept. 14, the re­search in­di­cates that over­con­fi­dence of­ten br­ings re­wards, as long as “spoils” of con­flict are large com­pared with the costs of com­pet­ing for them.

Over­con­fi­dence can br­ing suc­cess in sports, busi­ness or even war, the au­thors say. But they cau­tion that this bold ap­proach al­so risks wreak­ing ever-great­er hav­oc. They cite the 2008 fi­nan­cial crash and the 2003 Iraq war as just two ex­am­ples of when over­con­fi­dence back­fired.

“The mod­el shows that over­con­fi­dence can plau­sibly evolve in wide range of en­vi­ron­ments, as well as the situa­t­ions in which it will fail. The ques­tion now is how to chan­nel hu­man over­con­fi­dence so we can ex­ploit its ben­e­fits while avoid­ing oc­ca­sion­al dis­as­ters,” said study co-author Dom­i­nic John­son of the Uni­vers­ity of Ed­in­burgh.

The re­search­ers, from the Uni­vers­ity of Ed­in­burgh and the Uni­vers­ity of Cal­i­for­nia, San Die­go, used a math­e­mat­i­cal mod­el to sim­ulate the ef­fects of over­con­fi­dence over genera­t­ions. Their mod­el pit­ted “o­verconfident” play­ers against play­ers with ac­cu­rate per­cep­tions of their own abil­i­ties, and oth­ers that were un­der­con­fi­dent.

The var­i­ous groups’ suc­cess was meas­ured in terms of their abil­ity to pro­duce off­spring. That’s the meas­ure that sci­en­tists use in gaug­ing suc­cess in the ev­o­lu­tion of life, since the or­gan­isms with the most off­spring have the most in­flu­ence in de­ter­min­ing the shape and ge­net­ic make­up of fu­ture popula­t­ions.

The re­sults showed that over many genera­t­ions, the ev­o­lu­tion­ary prin­ci­ple of nat­u­ral se­lec­tion probably fa­vored a bi­as to­wards over­con­fi­dence, the in­ves­ti­ga­tors say. Nat­u­ral se­lec­tion is the pro­cess in which in­di­vid­u­als that are best-adapted to their en­vi­ron­ment tend to leave more de­scen­dants and en­joy great­er ev­o­lu­tion­ary suc­cess. 

In short, the re­search­ers found, peo­ple with the men­tal­ity of some­one like box­er Mo­ham­mad Ali would have left more de­scen­dants than those with the mind­set of film mak­er Woody Al­len.

The ev­o­lu­tion­ary mod­el al­so in­di­cat­ed that over­con­fi­dence be­comes great­est in the face of high lev­els of un­cer­tain­ty and risk. When we face un­fa­mil­iar en­e­mies or new tech­nolo­gies, over­con­fi­dence be­comes an even bet­ter strat­e­gy, ac­cord­ing to the in­ves­ti­ga­tors.

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Harboring a mistakenly inflated belief that we can easily meet challenges or win conflicts is actually good for us, new results from a simulation suggests Published in the research journal Nature Sept. 14, the research indicates that overconfidence often brings rewards, as long as “spoils” of conflict are large compared with the costs of competing for them. Overconfidence can bring success in sports, business or even war, the authors say. But they caution that this bold approach also risks wreaking ever-greater havoc. They cite the 2008 financial crash and the 2003 Iraq war as just two examples of when extreme overconfidence backfired. The researchers, from the University of Edinburgh and the University of California, San Diego used a mathematical model to simulate the effects of overconfidence over generations. Their model pitted “overconfident” players against players with accurate perceptions of their own abilities, and others that were underconfident. The various groups’ success was measured in terms of their ability to produce offspring. That’s the measure that scientists use in gauging success in the evolution of life, since the organisms with the most offspring have the most influence in determining the shape and genetic makeup of future populations. The results showed that over many generations, the evolutionary principle of natural selection probably favored a bias towards overconfidence, the investigators say. Natural selection is the process in which individuals that are best-adapted to their environment tend to leave more descendants and enjoy greater evolutionary success. In short, the researchers found, people with the mentality of someone like boxer Mohammad Ali would have left more descendants than those with the mindset of film maker Woody Allen. The evolutionary model also indicated that overconfidence becomes greatest in the face of high levels of uncertainty and risk. When we face unfamiliar enemies or new technologies, overconfidence becomes an even better strategy, according to the investigators. “The model shows that overconfidence can plausibly evolve in wide range of environments, as well as the situations in which it will fail. The question now is how to channel human overconfidence so we can exploit its benefits while avoiding occasional disasters,” said study co-author Dominic Johnson of the University of Edinburgh. strategy, study suggests