I wrote last week about Wesley So's loss by forfeit in round nine of the U.S. chess championship in St. Louis. It's only fair, then, to note that the 21-year-old So, one of the top 10 players in the world, has been on a tear ever since. He won his final two games in St. Louis, and now three of his first four at the Gashimov Memorial in Azerbaijan, one of the strongest tournaments of the year. His current score of 3.5 puts him in first place, ahead of the world champion. In other words, he's been playing great.

What accounts for So's ability to put the controversy behind him? One cannot say for sure, but a good guess is that optimism has a lot to do with it — specifically, what psychologists call "dispositional" optimism, an attitude in which we expect good outcomes rather than bad. It turns out to matter a great deal what stories we tell in explaining how we got to where we are. The more positive our stories, the better we tend to do going forward.

Studies of teenagers tend to confirm the thesis that "explanatory style" is a strong predictor of resilience. Explanatory style refers to the way an athlete reasons about his or her own performance. An optimistic explanatory style involves attributing bad outcomes to some particular event ("I was sick that day"). A pessimistic style invites a more global explanation ("I'm no good at this stuff"). The more optimistic the athlete's explanatory style, the easier to shrug off a bad performance.