People with higher scientific literacy are more polarized on climate change, not less. The smarter they are, the wider the gap between left and right (Kahan et al., 2012).
Intelligence isn’t closing the divide. It’s widening it.
When a Belief Becomes Part of You
In the previous chapter, you learned about motivated reasoning: you reason to defend, not to discover. And the backfire effect: counter-evidence can strengthen beliefs.
Identity-protective cognition explains why these happen with some beliefs but not others. The answer: it depends on whether the belief is fused with your identity.
Most beliefs are just facts you hold. “The capital of France is Paris.” If someone corrects you, you update. No drama.
But some beliefs are wired into who you are:
- Your political group’s positions
- Your religion’s claims about the world
- Your profession’s assumptions about how things work
- Your generation’s values
These aren’t just opinions. They’re membership cards. Changing them doesn’t just mean being wrong about a fact. It means betraying your group.
Your brain doesn’t ask “is this true?” It asks “what do people like me believe?” Being wrong is uncomfortable. Being ejected from your tribe is devastating.
The Numeracy Experiment
Kahan et al. (2017) designed an elegant study to prove this.
Participants were given a data table and asked to interpret it. The exact same numbers were framed two ways:
Version A: the data is about a skin cream study. Does the cream reduce rashes?
Version B: the data is about a gun control study. Does the ban reduce crime?
| Data framing | High numeracy participants | Low numeracy participants |
|---|---|---|
| Skin cream | Interpreted correctly much more often | Made more errors |
| Gun control | Interpreted to match their politics, regardless of the math | Same errors as before |
When the data was about skin cream, smart people crushed it. When the identical data was about gun control, smart people performed worse, because they used their math skills to find the interpretation that matched their political identity.
The higher your numeracy, the more selectively you used it. Smart people didn’t get closer to the truth. They got better at building sophisticated defenses for their side.
Why Intelligence Makes It Worse
This is the most counterintuitive finding in the field. You’d think education and intelligence would be the solution to polarization. They’re not. They’re fuel.
Higher intelligence gives you:
- Better tools for rationalization: more sophisticated arguments that feel objective
- Faster access to supporting evidence: you know where to look and what to cite
- More confidence in your analysis: “I’ve thought this through” feels true, even when it isn’t
- Greater ability to spot flaws in opposing evidence: selective scrutiny applied with surgical precision
A less intelligent person might say “I just don’t believe in climate change.” A more intelligent person says “The methodology of that study has significant confounds, and the confidence intervals overlap, and the IPCC’s models have historically overestimated warming.” Same conclusion. Better armor.
Kahan calls this the “tragedy of the science communication environment.” The problem isn’t that people are too stupid to understand the science. The problem is that they’re smart enough to weaponize it.
How to Spot It in Yourself
Identity-protective cognition is invisible while it’s happening. But these patterns are red flags:
- You evaluate evidence differently depending on which side produced it
- You can list 10 flaws in a study that threatens your view, but accept a study supporting your view without scrutiny
- Your confidence on a topic tracks with your group’s position, not with how much you’ve personally studied it
- Changing your mind would mean losing standing with people you respect
- You feel personally attacked when someone challenges the belief, not just intellectually disagreed with
The test is simple: would you evaluate this evidence the same way if it supported the opposite conclusion? If the answer is no, your identity is doing the reasoning, not your intellect.
What Actually Works
You can’t argue someone out of an identity-linked belief. The argument is the threat. But research suggests these approaches help:
- In-group messengers: a conservative climate scientist is more persuasive to conservatives than a liberal activist presenting the same data. The messenger’s identity matters as much as the message.
- Identity affirmation: Cohen et al. (2000) found that when people affirmed their core values before encountering threatening information, defensiveness dropped. Make them feel secure in who they are first.
- Decoupling belief from identity: frame the issue so that updating doesn’t feel like betrayal. “Smart people in your group are rethinking this” is more effective than “your group is wrong.”
- Curiosity over confrontation: Kahan (2017) found that science curiosity (as opposed to science literacy) did reduce polarization. Curious people seek out surprising information, even when it challenges their side.
You can’t force someone to choose truth over tribe. But you can make the truth feel safe for their tribe to accept.