A lot of the world’s biggest problems are what you might call crises of overconfidence.
Big, powerful nations conquer small, unstable ones expecting that invading troops will be greeted as liberators. On Wall Street, people who should know better buy dubious investments under the assumption that they’ll be able to unload them before the bubble bursts. And on Main Street, people already deep in debt purchase houses they can’t afford, reassuring themselves that prices can only go up. Meanwhile, the 7 billion humans on Earth keep pumping heat-trapping carbon dioxide into the atmosphere without seriously considering how their children and grandchildren will deal with the resulting climate disruption.
How on Earth did humans become such a self-deluding species? Why are we constantly fooling ourselves into doing things that are stupid not just in hindsight, but — given all the facts we have available — really didn’t seem like such a good idea even at the time?
It just may be that we’re victims of our evolutionary legacy. It’s quite possible, a pair of political scientists suggest in the Sept. 15 Nature, that back in the Stone Age, people who overestimated their own prospects for success actually benefited by it.
Why would political scientists be thinking about human evolution? Mostly because one of them is James Fowler, a professor at the University of California, San Diego whose past studies have found evidence that voting behavior is genetic and that having obese friends and relatives increases a person’s own chances of gaining weight. The obesity paper was published in that noted political science publication, the New England Journal of Medicine.
In their new Nature paper, Fowler and Dominic D. P. Johnson of the University of Edinburgh present a mathematical analysis that considers the effects of overconfidence during the evolutionary past. Back then, individuals and groups were presumably pitted against one another for access to things like food, shelter and the best rocks for making pointy weapons. When two people found themselves both reaching for the same chunk of flint, one of them would have to back down — or sparks would fly.
You’d think that the parties to these prehistoric showdowns would have a keen sense of how likely they were to prevail over their opponents. No point in making a fuss if you’re only going to end up with a face full of hairy knuckles.
But it turns out, Fowler and Johnson argue, that in most cases a potential combatant would actually be better off fooling himself into thinking that his chances of victory were higher than they really were.
The reason is that a fight is never a sure thing. That’s what used to make boxing interesting. It’s also one of the things that makes people think twice before shouting down some jerk who so badly deserves it: Maybe, just maybe, this 90-pound pip-squeak has a black belt.
Our ancestors had to do the very same calculus every time they saw something they wanted, Fowler and Johnson propose. After sizing up their rivals, they had to decide which of three outcomes would result if they grabbed that last hunk of zebra steak: One, they’d fight and win, gaining the benefit of the resource minus the cost of the fight. Two, they’d fight and lose, gaining nothing and sacrificing the cost of the fight. Or three, they’d get the resource and nobody would say peep.
What to do depends on the value of the resource to be gained: the nutrition in a delicious slab of mastodon meat, for example, relative to the cost of fighting over it — say, a black eye and maybe a bruised ego. If the value of the resource exceeds the cost of losing the fight by enough, Fowler and Johnson show, it really does behoove a person to think he’s Jackie Chan.
It’s true that a person with an inflated sense of his own fighting ability would inevitably end up losing whenever he overestimated his skill vis à vis his opponent’s. But those losses would be outweighed by the times that he claimed a resource and nobody else thought they could take him, even if they could. On top of that, such a person would almost never make the mistake of backing down from a fight with a weaker opponent.
The advantage of overconfidence is so powerful that it quickly spreads through a population once the rewards are big enough, Fowler and Johnson show. That means all you have to do is throw a little money or power or fame on the table, and pretty soon everybody thinks they’re better than everybody else.
Sounds familiar, doesn’t it?
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