In his terrific book Why We’re Polarized, Ezra Klein argues that identity is the answer to the question suggested by his title. The phrase “identity politics” has been thrown around a lot in recent years—usually in a negative context—but Klein explains that it’s human instinct to let our group identities guide our decision making. “A group can know more and reason better than an individual,” he says, “and thus human beings with the social and intellectual skills to pool knowledge had a survival advantage over those who didn’t.”

Why We’re Polarized is fundamentally a book about American politics, but I thought it was also a fascinating look at human psychology. One of my main takeaways was that many of us might need to reframe how we think about changing someone’s mind. I’m a data person (another identity I have!), so my instinct is always to use numbers and logic to convince people of something. When I meet someone who disagrees with me, I tend to explain the merits of my position and compare results of the two different approaches.

But Why We’re Polarized makes it clear that group identity can overrule any argument for or against an issue. If you want to bridge the gap, it’s more productive to appeal to someone’s identity than to their logic.

This is especially true for political issues. Klein explains how political identity used to be more rooted in where you lived rather than what party you belonged to. (This wasn’t always a good thing: He devotes an entire chapter to the damaging influence of the Dixiecrats.) The parties themselves were seen more as shortcuts you could use to inform your choices. “We may not know the precise right level of taxes… but we know whether we support the Democratic, Republican, Green, or Libertarian party,” Klein says.