Albert Einstein was one of the most important physicists of all time. His scientific predictions have withstood 100 years of scientific challenges. His thinking fundamentally changed the way we understand the universe. Yet people are more likely to be convinced Einstein wasn’t a great physicist than to change their minds on topics like immigration or the death penalty.

It has nothing to do with a person’s intelligence (or the quality of information on Einstein or immigration policy). It’s due to the fact that we’re simply more open to changing our minds on nonpolitical topics. Scientists have been keen to figure out why — because if they can, it may open the door to the hardest challenge in politics right now: changing minds.

Psychologists have been circling around a possible reason political beliefs are so stubborn: Partisan identities get tied up in our personal identities. Which would mean that an attack on our strongly held beliefs is an attack on the self. And the brain is built to protect the self.

When we’re attacked, we evade or defend — as if we have an immune system for uncomfortable thoughts, one you can see working in real time.

The blue checkmark of a verified account has become a marker of legitimacy on Twitter. Yet, like other invented status symbols, it seems men are more likely to have one.