“Somebody comes into your lab and you tell them, ‘You’re part of the blue team,’ ” he explains. “The next person who comes in, you flip a coin, let’s say it comes up the other way. And you say, ‘You’re on the red team.’ “
That’s it. The teammates never have to meet. Or interact. There doesn’t need to be anything at stake. But within minutes, these insta-partisans like their teammates better than they like the other guys. And it shows when Van Bavel puts his subjects through his MRI dollhouse.
Red-team members are more likely to see humans when they’re told they’re looking at fellow red-team faces. Blue-team members respond the same way. Other tests reveal that red-team members remember red-team faces more accurately, and if Van Bavel asks subjects to allocate money, red-team members will pay out more to their own. Team members also have less sympathy for those on the other side, and even experience pleasure while reading about their pain.
Jimmy Carter discovered one answer during the 1978 peace negotiations between Egyptian President Anwar Sadat and Israeli Prime Minister Menachem Begin. The talks were on the brink of collapsing in their final hours, and the prime minister was prepared to walk. That’s when Carter directed his secretary to find out all the names of Begin’s grandchildren. Carter autographed photos for them and personally gave them to the Israeli leader. “He had taken a blood oath that he would never dismantle an Israeli settlement,” Carter later recalled in an interview. “He looked at those eight photographs and tears began to run down his cheeks—and mine—as he read the names.”