The notion that our choices are driven by our own personal thoughts and opinions seems so obvious that it is not even worth mentioning,” Jonah Berger writes in the opening of his 2016 book, Invisible Influence: The Hidden Forces That Shape Behavior. “Except that it’s wrong.”
Berger, an associate professor of marketing at the University of Pennsylvania’s Wharton School, has made a specialty of researching why we make the decisions we do. In his first book, the best-selling Contagious: Why Things Catch On, Berger, 36, explored the hows and whys of ideas and products that go viral. This time around, he looks more deeply at the ways our choices are impacted by the messenger.
In Berger’s view, we are not as smart as we might think.
Often, he says, we are unaware of the influence that even the most peripheral people in our lives can have on our selections and preferences. These “invisible influences” have impact in a lot of different ways. We can imitate them, or work to differentiate ourselves from them.
One thing’s for sure: We kid ourselves when we think we can resist these invisible influences. “We love to think we’re renegades,” he says. “But it’s very hard to find someone who is truly a nonconformist. Usually, they’re just conforming to a different set of norms. We’re all influenced all the time.”
What are invisible influences, typically, and why do you call them “invisible?”
We think we make our own choices—most of the time, though, others are making those selections for us. And they’re not just our families and friends, but those we don’t know very well, like our colleague at work or the person sitting next to us on the train. I call them “invisible” because we often don’t realize that this influence is occurring—we say, I went to that movie because I like comedies.
What about our most important life decisions?
Same thing. The people we end up marrying can be shaped by whom we spend more or less time with. The house we buy can be shaped by how many days it was on market, which is based on whether other people were interested in it or not, we use that as a signal of how socially desirable the house is. What job we pick or career we follow depends a lot on who our roommate was in college or the people that were around us. These subtle factors have a big influence on our small life choices but an equally big influence on our larger, more important ones.
So, does this mean that we shouldn’t blame ourselves for bad decisions?
Just because we’re influenced doesn’t mean we have no control over what we’re doing. It’s hard to find a decision where we have nothing to do with the decision at all. So we’re certainly responsible for our bad decisions. What I think about it is that influence is a tool like any tool—there are ways to use that tool for good and for evil. It’s not necessarily the tool itself that’s good or bad, it’s how it’s used.
How does familiarity influence us?
Say our spouse gets something new and puts it in the house. We may not like it initially, but the more we see it, the more we like it. The more we’re exposed to something, the more familiar it becomes. Think of a song on the radio—if we don’t like it the first time we hear it, we hear it a few more times, we start to like it. The increased exposure has made us like it more because there’s a reduction in processing, we don’t have to do as much work. This has some neurological and developmental underpinnings and it shows up in all sorts of areas. We tend to like familiar things. We associate that warm glow of familiarity with liking.
Why do we park next to the only car in a parking lot?
The first driver has provided info about the “right” place to park. He or she has also shared something about the norms of parking. And, they’ve provided a focal point that encourages our attention or mimicry.
Being a rebel doesn’t mean not being influenced. Rebels may care a lot about the norm.
What if I choose to park on the other side of the lot, have I still been influenced?
Even when we think we’re being different, we’re being influenced. Avoiding influence doesn’t mean we’re still not subject to it.
So, is there no room in your argument for the true rebel?
I don’t think that person exists, and no data suggests that they exist. The key is to recognize that and use influence more effectively by, say, becoming more motivated to lose weight or save energy. Influence is neither bad or good, it’s a tool.
What would a true rebel look like?
Being a rebel doesn’t mean not being influenced. When we think of someone rebelling, we think of someone pushing back against something else but that may mean they were influenced by that thing to do something different. We often think of a rebel as independent when really what we end up meaning is a set of people that do something different than the norm, even though they may all be very similar to one another. Rebels may care a lot about the norm.
What about the loner, a person who goes his own way, does what he wants to do. Is that a false notion?
Try to figure out a decision that we’ve made where we didn’t look at what anyone else was doing or we weren’t shaped by anyone else’s opinion. It’s very hard to find—99.9 percent of all of our choices and behaviors are driven by others in some way.
How do we understand the idea of free will in this context?
It’s not that we’re mindless automatons or have no control over our own behavior. Certainly, we do. We pick what groups we want to be part of or are less interested in being part of and we’re influenced by those groups. We can pick which folks we want to be more influenced by or less influenced by based on who we surround ourselves with. People have said that you’re the combination of the five people that you spend the most time with—I think that’s an interesting way to think about it. We have some choice over whom we spend our time with, and those people in turn shape who we become.
Why are we so intrigued by the idea of the rebel?
Our research shows that no one wants to see themselves as influenced. Even in cases where being influenced is a good thing, we don’t think it happens to us—in part because it often happens unconsciously or below our awareness. The example of seeing someone more or hearing a song more and liking them more is a great example of that. We don’t realize that that’s why we like it more, but that’s why we do. We’re unaware of the influence on our behavior, even though it’s quite big and important.
In this coming  election season, there is both a larger-than-usual number of undecided voters, and an unusual level of ideological entrenchment. How do we reconcile that?
Voting is a signal of identity, it says something about us, and even being an undecided voter says something. Many people are choosing to say they’re undecided in this election because they don’t want to signal an association with either candidate. But our vote choice is not about whether someone or their policies are good or bad, it’s often about what that candidate says about those who support them. People have done a lot of studies looking at the effect of party over policy. You give Democrats or Republicans a policy and tell them it’s supported by either their party or the opposing party and they have drastically different opinions about that policy, depending on whether they think their party supports it or another one does.
Based in Philadelphia, JoAnn Greco writes about science, urban planning, and the arts for the Washington Post, the Wall Street Journal, The Atlantic’s City Lab, and the Penn Gazette.