Author Talks: Cass Sunstein on the perils of habituation

In this edition of Author Talks, McKinsey Global Publishing’s Roberta Fusaro chats with Cass Sunstein, the Robert Walmsley University Professor at Harvard Law School. They discuss Sunstein’s book Look Again: The Power of Noticing What Was Always There (Atria/One Signal Publishers, February 2024), cowritten with neuroscientist and professor Tali Sharot. It explores people’s propensity to habituate to both the good and the bad things in their lives and how that tendency can affect everything: personal relationships, careers, mental health, and how society functions. An edited version of the conversation follows.

Why this book, and why now?

The subject of habituation is maybe the most fundamental of all to our species. That is, people get used to things—habituate to them—and stop noticing them. Then, if they go away from one of those things, they come back, and they think, “Oh my gosh, that was my life”— and that might have an exclamation point or a question mark next to it, either one. There’s really no book on habituation, notwithstanding its fundamental character. You can find amazing papers in academic journals, often with footnotes, but there’s no book on habituation.

We’re in the midst of these years where some things in our lives are completely wonderful and fantastic. They might involve a beach, a home, or, for many, prosperity. Some countries are doing a lot better than they were before. Some people are doing a lot better than they were before. The wonders might include a neighborhood, a friend, and the internet. We don’t notice and celebrate them, and that’s a loss for each of us. If we have a good job, it might be a job that our grandparents would have been astounded to see even existed. We have that, and we just take it as part of life.

Also, these days, there are some things that aren’t so great. They might be corruption, crime, authoritarianism, domestic violence. You can take your pick. People habituate to those also. They don’t struggle to stop the negative thing, because it’s like life’s furniture.

Sometimes life’s furniture, which we don’t really notice much, is spectacular. It’s a loss that we don’t notice. And sometimes it’s really kind of crummy. It’s peeling, and we sit down on it, and it hurts us. We don’t notice the pain as much as we should.

What is happening in our brains when we habituate?

Let’s say we take 20 people and engage them in an experiment where they’re going to spend a day in a laboratory. They’re told they’re going to have an opportunity to make some money if they cooperate with their partner. They’re told, “This is a cooperation exercise, and if you’re part of a good team, you’ll make some money.” Then let’s suppose half of the participants are told, “Actually, we told you it’s about cooperation, but it’s got a little wrinkle in it. If you lie to your teammate, you’ll make more money. You’ll make more money if you don’t cooperate but lie.”

Normal people are being given an incentive to lie. The question is, what’s going to happen? If we look at people’s brain waves, it turns out, somewhat shockingly, that people will lie to make money under these conditions. A lot of people are going to lie. Now, it’s not a horrific lie. They’re not lying about criminality. They’re just misleading a teammate who’s a stranger. But they will lie.

The striking thing isn’t so much the lying. It’s that the amygdala, which is in the brain and roughly associated with strong emotions, is on fire at first. The amygdala is saying, “Oh my gosh, I’m lying. This is terrible.” That activity is highly visible to the experimenters. As the lies continue, however, the amygdala starts to quiet itself. As the day goes on, the amygdala gets less and less active. By the end of the day, the amygdala isn’t even noticing that the person in whose brain it sits is lying.

Basically when we’re engaged in conduct that makes us feel ashamed or guilty or horrible, if we do it a lot, our brain is going to stop registering—either as much or at all—that we’re doing something shameful or horrible. This is also true if there’s something joyful and fantastic happening—you’re falling in love, you’re ending up on a beach, you’ve gone to some new job that’s amazing, or you’ve found a colleague who’s just terrific to work with. After a while, the brain is registering this much less. And possibly, the emotional centers of the brain are registering it not at all.

When we’re engaged in conduct that makes us feel ashamed or guilty or horrible, if we do it a lot, our brain is going to stop registering—either as much or at all—that we’re doing something shameful or horrible.

What are the disadvantages of habituation when it comes to personal relationships?

Habituation in friendship and romance is a buzzkill. If you have a friend who’s an amazing friend, it may be that you cherish them and like being with them. But you don’t think a whole lot about their amazingness. I’m reminded I have a great friend in Chicago, whom I talk to periodically. The fact that he is such a fantastic person is something I don’t think about enough. But when I first got to know him, I thought, “Wow, how lucky that he’s in my university.”

We all have this thing with our colleagues. We don’t think to ourselves or say often enough, “It’s fantastic that we get to have this friendship.” People get used to family members in the same way.

Now let’s get a little adult. I was at a wedding not terribly long ago, and I happened to be sitting next to an expert on romance and sex. We started talking about marriage because we were at a wedding and this is what she does. I had known a little bit about her work but not a whole lot. She indicated that, in general, the early days of a romance are full of erotic energy. Then, after a while, even if both people are incredibly attractive in any way, married couples tend to be a little stultified. Habituation in the bedroom means that there isn’t any surprise or mystery. The basic problem is fire needs air.

And it’s not only about the bedroom; it’s about life generally. It’s about creativity in business. There’s a kind of chemistry that’s very important to innovation or to commitment. You can see this sometimes with someone who’s a boss, who you think, “I get to work for that person!” That’s the first week. By the third week it’s “That’s the person I work for?!”

Talk more about the link between habituation and, say, creativity and innovation in business.

Habituation is a killer of creativity and innovation. It’s a guarantee of steady dullness. In business, creative people find ways to dishabituate—by reading something that’s very different, by talking to someone who has very different perspectives, or just by taking a break and immersing themselves in something different—so they can go back to their situation with fresh eyes.

Habituation is a killer of creativity and innovation. It’s a guarantee of steady dullness. In business, creative people find ways to dishabituate so they can go back to their situation with fresh eyes.

Often, we’ll see someone—it might be Steve Jobs, it might be Thomas Edison—who just looks at something from a distance or brings to bear something from some other territory. Then we end up with a lightbulb or an iPhone.

What’s the link between habituation and the so-called midlife crisis?

Here’s the hypothesis about what happens to produce a midlife crisis—in the form of depression for some. It’s that people habituate to everything in their lives such that nothing is exciting or thrilling or joyful. Everything is a dull background noise, and that’s depressing.

If you’re 20, there may be tremendous struggles, but there’s endless opportunity and possibility. Once the kids leave the house and you’re, let’s say, 60 or 70, then there’s a new chapter. What are you going to do? That might be a little scary and disconcerting, but it’s also dishabituating.

Once you’re in a space where you have your partner, your kids, your job, your city, it’s lacking the kind of variety and openness that human beings crave and need. It’s a little like that episode of the old Twilight Zone show in which there was a character, a ne’er-do-well, who ended up in this place where there’s an angel. The angel gave our hero, the small-time crook, everything he wanted all the time.

The small-time crook eventually started to lose his mind because anything he wanted, he got. He turned to his benefactor angel and said, “I can’t take it anymore. I want to be in the other place.” The angel looked at him and said, “Mr. Valentine, this is the other place.” For people who are doing well in midlife, they’re in their own version of the other place.

What steps can individuals take to surprise themselves or to break out of old habits?

Let’s start with a little data. When people go on vacations, the data suggest that the high point is 43 hours in. At 43 hours into a vacation, people are really having a great time. It’s all downhill from there. It’s less great.

At first, you’re planning, you’re packing, it’s fantastic, and it’s great, but you’re not there yet. At 43 hours in, you’re there, you’re settled, and you’re still amazed by the place. At that point, though, it starts being the place where you’re on vacation—a little less amazing, really good, but not as phenomenal as it was at the beginning.

That data point is suggestive about how to dishabituate, which is to try to move things in the direction where everything is like that 43rd hour of vacation. Now how can you do that?

There are three things that people care about. First, they care about happiness. They want to be smiling rather than scowling. Second, people care about meaning or purpose. If you have a life that’s full of smiles and laughter, but it seems kind of pointless, people will get a little bored and feel a little less thrilled after a week. They’ll think, “Well, what’s it all about?” Third, recent data show that people also care about psychological richness—understood as variety of life. They want something different on Thursday from what they experienced on Monday. People really need that, and you can engineer that.

At work, with the aid of your employer, you may venture into new enterprises, taking on tasks that are different from those you’ve taken on before. That sounds a little simple, but it can be completely thrilling for people. Once they go back to their former work, they still retain a sense of adventure and novelty. They often produce insights that are unexpected and wouldn’t have occurred if not for the fact that they did something different for a while.

I see this in the US government, where I’ve worked periodically, when people are detailed to other places. Someone who works for the Environmental Protection Agency [EPA] may be detailed to the White House. Then they come back to the EPA full of energy and new insights and a sense that “this job at the EPA is a really cool job, and I understood that less when I didn’t have breaks from it.” The idea of rotating into different roles is a really good idea, even if the role into which people rotate is one they don’t like it as much as the job that they rotated from.

Part of the energy of the book comes from an unlikely place. The actor Julia Roberts was interviewed in the New York Times in the early stages of working on this project. The interviewer asked, “What, for you, is a perfect day?”

Ms. Roberts spoke about preparing meals for her children and husband, watching TV, and picking up her children at sports practice. Then she stopped herself and said, “I know this is really boring.”

She added that her career often takes her away from her family. So when she returns home, “It’s surrounded by pixie dust. It ‘resparkles.’” And the notion of resparkling seems profound.

I am currently in Concord, Massachusetts, where the American Revolution started. Outside it’s sunny and pretty. There’s a street that is easy to drive on, and there are really nice people at the local store.

I confess I haven’t thought about all that I’ve just described, except in the context of resparkling. And for any of us, even if we’re under circumstances that aren’t ideal, there are probably ten things that are great that could use a little pixie dust.

What surprised you most as you were researching and writing this book?

One thing that surprised us as authors was the idea that it’s often good to break up great tasks and motor through the terrible ones. This is totally counterintuitive. If people are having a good experience with music, let’s say, or a massage, the idea of breaking it up sounds terrible. We want to just keep enjoying what we’re doing. But the research suggests that if you break it up, it gets better.

This is asymmetrical for bad tasks—such as cleaning up a big mess—where the idea of breaking it up into three stages sounds very appealing. But if you motor through and do it in one long stretch, you’ll habituate to it, and it won’t be so terrible. Whereas if you revisit the same bad task three times, the terribleness of cleaning up the mess is going to reassert itself each time you restart. So break up the good and motor through the bad.

How can organizations help with habituation?

The phenomenon of habituation has yet to receive the kind of attention that it deserves, given how fundamental it is to human life. If you’re in an organization that depends on innovation, you need people to be innovative—and we know from experiments that there are little things that organizations can do to facilitate that.

For instance, if people sit, they’re less creative than if they stand up and walk around a little bit. That’s a very simple task. If you’re stuck, maybe stand up and walk around a little bit, interact with someone new. The high jumper, Dick Fosbury, who’s a hero of the book, invented the Fosbury Flop, which was a completely different way of high jumping when he started doing it. He did it partly because he wasn’t so great at jumping the normal way but partly because he had some capital in his head, which he could tap to try to think of something new.

Every one of us has some capital in our head. The question is how to tap it. For an organization to have something like a “dishabituation project”—let’s just call it that—for six months is likely to pay big dividends.

When I worked in the Obama administration, I saw that inserting new people in positions would often spur thoughts that no one had had for months. They were not routinized. The parts of one’s brain that are activated if one is in a new setting were activated for them. So they would have several ideas. Perhaps two-thirds of those ideas were not good ideas. Yet if you get one-third that you can actually implement to help economic growth or to reduce unemployment, that’s great.

Can habituation sometimes be a good thing?

If we didn’t habituate, then our brains would be so distracted by everything that we couldn’t focus on what we need to focus on. So while habituation is a problem, it’s also a solution. All creatures are very reactive to change and relatively unresponsive to stability. And that’s evolutionarily a good thing. In many ways, it’s also a good thing in human life.

If you’re doing fine and not burning up or freezing, and no lion is eating you, to be very indifferent to things is fine because everything around you is fine. But if you hear a sudden roar, then to be extremely reactive and maybe to run is smart because that roar is unfamiliar, and it’s threatening.

If people didn’t habituate, they wouldn’t know what to focus on. I’d be looking at, let’s say, the laptop in front of me or the wall in the distance with such amazement and focus and attention. And if a lion did attack, or if something else really needed my focus, I wouldn’t have enough bandwidth to attend to it.

Does all change have to be big, or can incremental changes help us dishabituate?

There are data suggesting that with respect to big, bold changes and greater-than-incremental changes, if you’re thinking seriously about whether to make the change, you probably should. If you’re seriously thinking of changing your job or developing a new hobby or doing something big, such as going to another city, the data suggest that you probably should—not definitely, but probably.

If you’re not thinking about it, don’t quit your job, and don’t go to a new city. But people tend to err in the direction of sticking with the status quo a bit more than they should. That’s partly because they’ve habituated to where they are, and the idea of dishabituating is scary.

But what about the bad things in the new place? They’ll get used to those. The bad things won’t be so terrible, and the good things will be less thrilling after a while than they were at the beginning. But giving more change a chance is probably a good idea.

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