Tom Brady’s fans are quick to rationalize the Patriots’ woes. (Mark Humphrey / AP)

Eric Simons is the San Francisco-based author of “The Secret Lives of Sports Fans: The Science of Sports Obsession.”

Two weeks ago, a man who earns his living by chasing other men in pursuit of a leather prolate spheroid handed a team staffer a football that felt soft. The staffer reported this unusual occurrence to his supervisor, who reported it to his supervisor, who reported it to his supervisor, and then all hell broke loose. Ever since, the nation has been held in thrall to the spectacle of sports fans debating the ideal gas law .

The scandal has acquired its own name, DeflateGate, and let’s be real: You have an opinion on this matter, and I have an opinion on this matter, and people who hate prolate spheroids and listen only to public radio have an opinion on this matter. The intensity of the reaction to whatever the New England Patriots did to their footballs has been proportionally ludicrous.

Nonetheless, two weeks of football-deflation conspiracy theories is a fitting capstone for an NFL season defined by responses to controversy. For six months we’ve watched fans rally through scandal to support their teams. Baltimore fans backed Ray Rice after he beat his future wife on video, Washington fans defended the team’s offensive name, and football fans rationalize the head trauma that players endure. Obviously, this is not exclusive to the NFL — Dutch soccer fans embraced the diver Arjen Robben, who drew a World Cup game-winning penalty kick against Mexico by falling theatrically after, er, minimal contact — or even to sports. (See: politics.) The home team gets a knee-jerk defense, no matter the evidence against it — and other teams get schadenfreude when the ball deflates the other way.

This is not, however, evidence of cognitive failure. Actually, we’re all acting quite reasonably.

A sports team is an expression of a fan’s sense of self, as I learned from dozens of interviews and research articles I surveyed for my book “The Secret Lives of Sports Fans,” is an expansion of a fan’s sense of self. It is not an obnoxious affectation when a devotee uses the word “we”; it’s a literal confusion in the brain about what is “me” and what is “the team.” In all kinds of unconscious ways, a fan mirrors the feelings, actions and even hormones of the players. Self-esteem rides on the outcome of the game and the image of the franchise.

There are benefits to this: not just self-esteem but pride, identity, belonging. There is also a downside: You are quite biased toward yourself and your in-group. And if your relationship with a sports team makes your brain think that the sports team is you, and you are me, and we are all together, then it also applies a lot of those biases to the actions of the team. When the team is accused of skullduggery with the ball pump, it’s the fan’s instinct to explain and rationalize. For the invested fan, deflecting DeflateGate is an act of self-preservation.

A famous study in perceptual bias actually comes from football. A researcher studying a 1951 football game between Dartmouth and Princeton noticed that fans simply could not agree on what had happened. The game had been “rough,” they generally concurred. (Star players from both teams left the game with injuries.) But was it fair? And who started the rough stuff? It depended on which team you liked.

Even when fans watched film of the game later on, they drew no closer to consensus. In “They Saw a Game: A Case Study,” psychology professors Albert Hastorf and Hadley Cantril laid out a Rashomon theory of history in the Journal of Abnormal and Social Psychology: No one can perceive anything accurately through the fog of the gridiron.

Sports fans see things that way for the same reasons partisans do in political, cultural and scientific controversies: That’s how people behave. We are consistent in the way we weigh evidence and assign blame, whether we are considering Bill Belichick, Barack Obama or climate change, according to my research.

One of the first to notice this was Henri Tajfel, a Polish-born British psychologist who had survived a Nazi prisoner-of-war camp in World War II and lost most of his family in the Holocaust. In the 1960s, Tajfel started a series of experiments on the “monotonous similarity” of discrimination. He brought a number of schoolboys into his lab in Bristol, England, to see just how arbitrarily he could divide them before they started treating each other horribly.

The answer was: trivially. Boys divided by the simplest thing Tajfel could come up with — a false assignation of whether they had overestimated or underestimated the number of dots on a screen — still mistreated out-group members, even though there was no real reason to, and even at the apparent expense of individual interest. Given small amounts of money to dispense, they disproportionately rewarded members of their own group at the expense of the others. The reasonable courses, Tajfel wrote, would have been either to maximize the amount everyone took home (since, after all, the boys all knew one another) or to choose the fairest option. Introduce even those arbitrary groups, though, and fairness vanished.

And sports fan bases are not trivially sorted groups. Athletic teams offer not just a connection with the players and fellow fans, but also with regional pride, family relationships, color preferences, aesthetic tastes and even moral standards. Teams or players can assume religious, ethnic or political identities — such as Tim Tebow’s overt Christianity or FC Barcelona’s traditional ties to Catalan autonomy — further ensnaring the loyalties of their fans.

If we mapped the brain of a sports fan as she looked at her favorite team or player, says Arthur Aron, a psychologist who has studied interpersonal relationships for decades, we would expect to find a response similar to the one she has when she looks at a picture of her spouse. Neuroscientists such as UCLA’s Marco Iacoboni say that the brain’s “mirror” neurons underlie fandom by putting fans’ brains in sync with the brains of their teams’ players. Endocrinologists have shown repeatedly that fans’ hormonal responses (particularly in men) can mirror the responses of the players who are competing. Put it all together and it’s no surprise to find, as Arizona State psychology and marketing professor Robert Cialdini first did in the 1970s, that the use of the royal “we” increases after wins and decreases after losses as fans “bask in reflected glory” or “cut off reflected failure.”

Sports may have no cosmic significance, in other words, but to their followers, they matter. As such, it’s entirely rational for a fan to defend his or her identity against outside attack. It is rational to seek an extra level of proof in allegations that might harm you. It is rational (if intellectually dishonest) to forgive or explain the behavior of in-group members.

Maybe a better question is: If that’s what you’re up against every time you make an evidence-based argument, what do you need to do to change a biased, rationally self-interested person’s mind? Can we learn anything from sports that might help mediate the seemingly intractable political and cultural problems of modern America?

Perhaps we can learn that everyone has a price. Fans are an illustration of the way invested people might demand a higher standard of evidence, or a different presentation of the evidence, than other people would. But maybe they are also a reminder that evidence and context matter. There was genuine outrage, even among Baltimore fans, about Ray Rice. The “Jacked Up” segments celebrating head-to-head contact have disappeared from ESPN. The number of people who think “Redskins” is an acceptable name has dropped slowly but surely for two decades. It is frustrating, and occasionally infuriating, to watch the glacial pace of change. But change comes nonetheless.

DeflateGate is the most ridiculous, least important of all of these issues, so we may have to take our comfort from a lesser place: A lot more sports fans now know about the ideal gas law.

Twitter: @ericsimons

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