Your recent study sheds light on a trait that seems at odds with the concept of cooperation: overconfidence. Can you elaborate?
We built a mathematical model to see if overconfidence would persist in an evolving population. In this model, two individuals each have a certain level of capability, which they over- or underestimate while deciding whether or not to compete against their opponent for a resource, like food. If neither claims the resource, then neither gets anything. If both claim it, then the more capable individual wins and gets the food. But if neither individual has a clear advantage, one of them might walk away from the food, and the other, if he has an inflated opinion of himself, can get that food for free.
What did you find?
On balance, it makes sense to be overconfident whenever the value of the resource is bigger than the cost of conflict. One way this works is if your survival is at stake.
How did this play out in human evolution?
Imagine village life tens of thousands of years ago, before fire. Food is probably much more valuable than it is in modern times: Whether or not you eat today has an impact on whether or not you’ll survive tomorrow. But technology is still lacking: We don’t have knives; we don’t have guns. If you go back far enough, we may not even have stone tools. The cost of conflict is much lower, in the sense that you may have a fistfight, but you probably won’t die—at least not as easily as you’d die today. Now imagine that our brains evolved in this state, with very beneficial resources at stake and conflicts that you could probably survive from day to day, and it makes sense why overconfidence would be advantageous.
Does that advantage still hold true today?
It still does in any situation where something is set up tournament-style and people can be eliminated. One example is competing for a promotion in the workplace. In this case, we’re not talking about survival literally in that if you don’t get the promotion, you’ll die. But we’re talking about survival in the sense that the people at the top have already gone through this tournament process where they competed for promotions and won repeatedly. So people at the top of an organization tend to be more overconfident, in the sense that they have survived more rounds of selection than those just starting.
It’s hard not to think of the people who directed their financial institutions to take on bundled mortgages and other high-risk investments. Is there a downside to overconfidence in corporate leadership?
An overconfident person exposes everyone to more conflict and risk, jeopardizing the group.
If overconfidence could have such destructive effects in
the modern world, why does
Because it is a good gamble for an individual to risk conflict to be personally better off, even though society benefits most when there is no conflict. Natural selection acts on individuals, not society as a whole, so overconfidence can evolve even if it is costly to the population.