Overconfidence, par Malcolm Gladwell
This is what social scientists mean when they say that human overconfidence can be an adaptive trait. “In conflicts involving mutual assessment, an exaggerated assessment of the probability of winning increases the probability of winning,†Richard Wrangham, a biological anthropologist at Harvard, writes. “Selection therefore favors this form of overconfidence.†Winners know how to bluff. And who bluffs the best? The person who, instead of pretending to be stronger than he is, actually believes himself to be stronger than he is.
[…]because ability makes a difference in competitions of skill, we make the mistake of thinking that it must also make a difference in competitions of pure chance. Other studies have reached similar conclusions. As novices, we don’t trust our judgment. Then we have some success, and begin to feel a little surer of ourselves. Finally, we get to the top of our game and succumb to the trap of thinking that there’s nothing we can’t master. As we get older and more experienced, we overestimate the accuracy of our judgments, especially when the task before us is difficult and when we’re involved with something of great personal importance.
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Of course, one reason that over-confidence is so difficult to eradicate from expert fields like finance is that, at least some of the time, it’s useful to be overconfident—or, more precisely, sometimes the only way to get out of the problems caused by overconfidence is to be even more overconfident.