The Psychology of Belief

How your brain distorts the world to support your emotional attachments to certain ideas

Belief is a powerful and necessary thing, governing our societies, our day-to-day and inner lives, our thoughts, hopes, plans, and relationships. You believe that the plane will leave the runway, that working hard will lead to a promotion, that the candidate you support is the best one for the job. Some things you believe because a pattern of experience suggests you should: The sun has come up every morning so far, so why should tomorrow be any different?

But other things you believe even despite logic and evidence to the contrary: The next lottery ticket you buy will be the big one, you can feel it.

Belief is like that; some things you believe because you just do. No one, no matter how brilliant or how educated, is immune to irrational convictions, says Paul Zak, a neuroscientist at Claremont Graduate University. For example, “Linus Pauling was a two-time Nobel Prize winner, one of the most respected scientists ever, and he believed vitamin C was a cure-all for things and spent a lot of years pushing it despite being totally unsupported by medical evidence,” Zak says. “He was as smart as they come, but he deluded himself that this thing was true when it wasn’t.”

That’s because the relationship between belief and fact often goes one way: “Our brains take the facts and fit them to reinforce our beliefs,” Zak says, and those beliefs don’t need to make sense to be deeply held. It’s a relationship that has both benefits and drawbacks — but knowing when it’s helping and when it’s doing us a disservice requires an understanding of how we form emotional attachments to those beliefs.

“To become aware of our biases, we need to understand how our emotions play a role in our decision-making and belief processes,” says Jonas Kaplan, a professor of psychology at USC’s Brain and Creativity Institute. “Most of the time, it’s a good thing. It’s an old, wise, biological system that’s there to help us, but it’s not always relevant to modern life.”

Our earliest beliefs begin to form long before we’re even really cognizant of them. Our brains, Zak explains, are designed to look for patterns, which “allow us to navigate through the world, survive, and reproduce.” Eventually, our dependence on a pattern becomes a belief in its power.

Some of those early beliefs form through observation. For instance, “by about three months old, children understand gravity,” Zak says. “They believe that if you drop a ball, it will hit the ground. So, if you let go and the ball hovers in the air, those infants will look at it like, ‘What the hell?’ The hovering ball violates this tenet they’ve already come to believe.”

Other beliefs are passed along to us from our families and communities, who transmit many of the foundational ideas that shape how we see the world. Evolutionarily speaking, we are herd animals, and there’s an advantage to going along with the crowd. Those group beliefs, in turn, work their way into our most basic concept of who we are. “The systems in the brain that light up when we access our beliefs are the same systems that help us understand stories,” Kaplan says. “We see a lot of the same brain systems involved when people think about who they are and about the beliefs that are most important to them.”

Kaplan describes a neural system known as the default mode network, a set of interconnected areas of the brain associated with identity and self-representation. “It’s the area that lights up in brain imaging when you ask people to lie there and do nothing,” he says. “Of course, they’re not doing nothing. They’re thinking — about themselves and their future and their plans. It also lights up when people read stories with values they consider deeply important to them and when people think about their political beliefs.”

When your most deeply held beliefs are challenged, “many of the most biologically basic brain systems, those responsible for protecting us, kick into high gear.”

In a study published in 2016 in Scientific Reports, Kaplan and his colleagues conducted brain imaging on participants as they read arguments that contradicted their views on issues, both political and nonpolitical, and documented their neurological response to the opposing information. The results of the team’s persuasive efforts were mixed. “We were able to change minds about things like whether Thomas Edison invented the lightbulb and if multivitamins are important,” he says, but other beliefs — those Kaplan calls the “sacred values” — were all but immovable.

The reason those so-called sacred values are so difficult to change, Kaplan says, is that they’re surrounded by a complex network of mental safeguards. When your most deeply held beliefs are challenged, “many of the most biologically basic brain systems, those responsible for protecting us, kick into high gear,” Kaplan says. “These are things like the amygdala, which tells you when to be afraid, and the insula, the part of your brain that processes visceral feelings from the gut and tells you things like if you’re encountering food that’s bad for you. We have a strong motivation to defend those sacred values.”

Of course, not every belief is sacred. So, what determines the strength of our convictions and sets the ones worth protecting apart from the rest? Most of the time, it’s tied to our emotions.

“When you establish your beliefs, if they include emotional tags, the brain saves that information differently so it’s more accessible and impactful,” Zak says. “The strongest beliefs are tied to things like 9/11 or the birth of a child; highly emotional events create beliefs that are almost impossible to change.”

So much of our identity is social, and so many of our social connections are founded on shared beliefs. Ultimately, Kaplan says, most people find it simpler to maintain both their established beliefs and their social circle than to consider a drastic value shift, for reasons that are as practical as they are mental.

“People say, ‘I can’t change my mind. What would my friends think of me?’ People who radically change their political beliefs, for instance, lose a lot: social relationships, jobs, romantic partners,” he says. “There’s a lot at stake when you’re considering changing a belief.”

Our tendency to cling to our beliefs may feel better than the alternative, but that doesn’t mean it’s in our best interest. Our primary self-defense tactic is to remove the threat and avoid anything that might challenge our worldview, which is how so many of us end up living in a feedback loop, surrounded by people who share the same opinions. The effect is only exacerbated by our reliance on social media.

“The world is an information minefield right now,” Kaplan says. We also need to think carefully about which beliefs we allow into that protected inner circle, he adds. “It makes sense to share beliefs and values with people, and it makes sense to defend those beliefs. But to have beliefs that are epistemological — that things are true or false about the world — and be unwilling to hear otherwise could be very dangerous.”

As for all the other little beliefs tucked away in your head, Zak says, you don’t necessarily need to interrogate everything. “Praying the plane lands safely probably doesn’t change anything, but what’s the harm?” he says. “If holding on to the hope that winning the lottery is the solution brings you comfort, why not?”

“If you don’t have some beliefs, you just can’t get through the world,” Zak says. “These rituals and beliefs are really reinforcing, they’re really nice, and there’s something beautiful and distinctly human about them.”