Katy Milkman: In the ancient Greek epic poem The Odyssey, the hero Ulysses and his men have to sail past an island inhabited by sirens. The sirens were creatures with vulture-like bodies and grotesque human heads, but they sang hypnotizing songs that were so enchanting sailors were lured to wreck their ships against the rocky shores. They couldn’t resist the tempting pull of the beautiful music.
Ulysses heard stories of the sirens and developed a plan to outsmart fate. He instructed his men to fill their ears with wax to avoid being lured towards land by the sirens’ song. But Ulysses was curious to hear the song for himself, even though he knew he wouldn’t be able to resist it. If he heard it and had control of his ship, he would steer his crew to a watery grave. So he ordered the sailors to tie him to the ship’s mast so he couldn’t move or sway their course.
As their ship approached the legendary island of the sirens, Ulysses was overcome by the temptation to follow the sound of the beautiful song. He implored his men to steer towards the sirens, but the sailors had wax in their ears. They couldn’t hear the song or Ulysses’ pleas, and so they sailed on past the rocky shores.
You might be wondering why I’m telling you this ancient story. Well, it turns out that the strategy Ulysses employed for avoiding temptation was a pretty good one. I’m not suggesting you tie yourself up exactly, but in this episode, we’ll look at related strategies to help you resist temptations and stick to your goals. Then we’ll consider the science behind these strategies with behavioral economist and best-selling author Dan Ariely.
I’m Katy Milkman, and this is Choiceology, an original podcast from Charles Schwab. It’s a show about the psychology and economics behind human behavior. We bring you true stories involving high-stakes moments, and then we explore the latest research in behavioral science to help you avoid costly mistakes.
The mythical Ulysses had an effective strategy for avoiding temptation, but I want to tell you another short story. It’s not an ancient myth, though some parts of this story may seem too strange to be true.
Paris, 1830. The author Victor Hugo faces a looming deadline. The year before, he’d committed to deliver a new book to his publisher, Notre Dame de Paris, also known as The Hunchback of Notre Dame. But Hugo had been procrastinating. He’d spent much of the year working on plays, entertaining guests, and exploring the older neighborhoods of the city he loved. After Hugo delayed delivering his manuscript for the umpteenth time, his publisher got frustrated and set a firm deadline. Hugo would have to deliver the manuscript in February of 1831 or else. That was less than six months away, and he was nowhere near finished. So he came up with a plan.
According to an account by his wife, Adele, Hugo bought himself a bottle of ink and a huge gray knitted shawl, which “swathed him from head to foot.” Then he locked his formal clothes away and presumably gave the key to someone else for safekeeping.
Now that he had no clothes to go outside, he wasn’t tempted by the distractions of city life. Entertaining wasn’t an option either. He wouldn’t dare invite guests over to visit without appropriate clothes to wear for the occasion. Having just a shawl and pen, ink, and paper, his only option was to write. Hugo’s wife said he entered his novel as if it were a prison, but the strategy worked. Victor Hugo remained in his study for hours and hours each day. He wrote furiously into the fall and winter of 1830. The Hunchback of Notre Dame was published on January 14th, 1831, two weeks ahead of the publisher’s deadline. It went on to become a classic of Western literature.
Both the story of Victor Hugo’s struggle to write and the Greek myth of Ulysses and the sirens illustrate colorful ways for avoiding temptation and sticking to goals. Now I’ve got one more story, but this one is probably more relatable.
Dean Karlan: Hi, my name is Dean Karlan. I’m a professor of economics and finance at Kellogg School of Management at Northwestern University.
Katy Milkman: Dean is also a cofounder of StickK. That’s S-T-I-C-K-K, a website and an app that helps people commit to changes in their lives that they’d like to make. Sticking to goals is personal for Dean.
Dean Karlan: When I moved to Chicago, I discovered deep-dish pizza, which is not really pizza—it’s more like a casserole—and ate too much of it. And by the time I moved to Cambridge to go to graduate school, I had gained more weight than I had ever gained in my life. And it was eye-opening, and I knew I needed to something about it. But just as with anybody, losing weight is hard. So I would go up and down and up and down and up and down, but not by too much, and never really achieved my goal of getting rid of all those pounds and getting back to my honeymoon weight. And I had a friend who was experiencing similar—no longer young, active, able-to-eat-anything body. And the two of us were lamenting that we had the same basic issues, that we were 10 years past our prime and heavier than we wanted to be.
Katy Milkman: This will be a familiar story to many people. Your metabolism drops as you age, but the temptation to eat things like deep-dish pizza is sadly a constant.
Dean Karlan: So I was around 210, and I wanted to get down to 170.
Katy Milkman: Luckily, Dean’s field of study gave him some insight into his predicament.
Dean Karlan: One of the basic ideas in behavioral economics is that people are not always consistent over time in how they behave. And you might say you want to do something, and when the time comes, immediate temptations take over, and you don’t do the things you say you’re going to do. When I reflected on my own life—realized, wait a second, I have a way of doing this in my own life, and maybe I can change this one behavior that is the most troubling to me on a personal level. And so a friend of mine and I, we turned to each other and said, “Well, why don’t we see if we can apply these theories to our own life and make this contract with each other?”
Katy Milkman: The stage was set for a small two-person experiment. The volunteers were Dean and his friend Kurt.
Dean Karlan: We both needed to lose roughly the same amount of weight. And so we gave ourselves a sufficiently healthy period of time to lose the weight. And we made an agreement that said if we both lost the weight that we wanted to lose, then no money exchanged hands. But if one lost and the other did not, then they owed the other person money. And we agreed that you could not offer to renegotiate the timing of the contract, that the mere suggestion of delaying was an immediate forfeiture. So I don’t remember whether we wrote it on a piece of paper or an email. I suspect we just wrote an email and kind of wrote it out.
Katy Milkman: No matter how they wrote the agreement, they made sure the stakes were high.
Dean Karlan: So we basically put up about half of our stipend from graduate school. I think it was about $10,000, which is a lot of money. And we agreed to an arrangement that said we have to lose weight, and if we don’t lose weight, we owe the other one a lot of money.
Katy Milkman: Managing temptation is a difficult challenge. So in addition to leveraging the threat of losing money on a large scale, Dean employed the same strategy on a smaller scale against smaller temptations.
Dean Karlan: I did find very consistently, if I would order wine and drink wine at dinner, then it would be much harder for me to resist the nice dessert at the end of the meal. I knew that once I had the wine, I would then succumb to the temptation of dessert. So I did have a little mini workaround on that that I did, and that is I would turn to a friend at dinner, and I would say, “Hey, let’s order wine. But if I succumb to the temptation of dessert, I owe you $100.” And that would work perfectly because then I could enjoy a couple of glasses of wine, dessert menu would arrive, and I’d say no. Because I’m not going to spend $100 more for dessert even if I’ve had a few glasses of wine in me.
Katy Milkman: This strategy of putting money on the line worked well for both Dean and his friend Kurt. Now they had to figure out how to make it last.
Dean Karlan: I think we were both really fairly well behaved, and we got our act together, and it was a slow, steady, healthy weight loss throughout that process.
So after we lost the weight, at some point, a couple years later, we realized that we needed a maintenance agreement in place. There was a clause that said if the other one shows up at the other person’s door or sees them at a conference or wherever we can demand a weigh-in the next day. And that worked for a couple of years, but then he did creep up, and we went for about a year without seeing each other and then saw each other at a conference, and unfortunately he had gained weight. And so then it was an important moment because that was the moment at which to enforce, I wasn’t just being greedy, but it was really actually in my own self-interest for the weight loss to demand the money because I wanted the arrangement to continue. And I wanted him to lose weight. So I did demand the money. He paid.
Katy Milkman: In the end, Kurt had to pay $15,000 for gaining weight. And while this must have stung for Kurt, it inspired Dean to take the idea one step further.
Dean Karlan: And so basically we had this idea of could we actually set this up in a way that allowed individuals on their own to write a commitment contract? So the initial idea I had was to create a company called the Commitment Store. At some point we morphed the name and called it StickK, with a second K.
Katy Milkman: StickK has an extra K for two reasons. One, capital K is legal shorthand for contract. But number two is that the website Stick.com with one K was already owned by someone else.
StickK is a company Dean founded to let people create these kinds of commitment contracts at scale. I should say, this is certainly not an ad for StickK. There are a number of different websites and apps now that let you set up contracts like this, including Beeminder, LifeRPG, and Strides. But Dean designed StickK before other options existed to help people commit to goals by setting stakes they would have to forfeit if they gave into temptation.
Dean Karlan: Dominant uses, of course, are what you would expect: weight loss, exercise, smoking. But the exciting thing about it is that people can write any goal they want on the website and let it be open for whatever behavior they want to change. Flossing more, doing their homework more, waking up by a certain time of day.
You know, people can be very creative and write whatever contract they want that pertains to some area of their life that they’re trying to change. So I think my favorite weird contract that was ever put on was someone who said, “I commit not to dating any more losers” and had a friend who got to adjudicate whether her dates were losers or not.
So we’ve seen a lot of money put on the line. We’ve seen about 40, 41 million dollars historically put on the line and at stake over 450,000 contracts. We’ve seen about a million different workouts being reported as achieved and nine million cigarettes no longer smoked that would have otherwise been smoked.
Katy Milkman: Dean’s takeaway is pretty simple.
Dean Karlan: Basically, you need to increase the price of your vice. That’s basically the punchline of what a commitment device is. Recognizing that when that moment comes for that temptation, whatever that is, it’s too cheap in the kind of normal environment that you’re going to face that temptation, and you need to make it more expensive.
But there does come a point where you need the long-term habit to just be long-term habit. It’s probably not the case that you want 50 years of financial contracts hanging over you in order to engage in healthy eating and healthy exercise behavior.
At some point, the habit needs to stick and be part of your daily life without having to constantly have financial contracts hanging over you. The financial contracts can be helpful for getting your act in gear, getting the habit formed, maintaining it for a bit. But in the long run, you do need to take it upon yourself to just maintain that lifestyle.
Katy Milkman: Dean Karlan is a behavioral economist and professor of economics and finance at the Kellogg School of Management at Northwestern University. He’s also a cofounder of StickK and the coauthor of several terrific books, including More Than Good Intentions: Improving the Ways the World’s Poor Borrow, Save, Farm, Learn, and Stay Healthy. I’ve got links in the show notes and at schwab.com/podcast.
What Dean calls increasing the price of your vice is an example of what’s known in behavioral science as a commitment device. Victor Hugo locking his clothes away was a commitment device. Being tied to the mast was a commitment device for Ulysses, fictional though he may be.
A commitment device is a choice you make in the present that restricts or changes the price of your vice in the future. The idea is to influence future behaviors that might be impulsive and thereby reduce their likelihood of occurring.
Commitment devices make it easier to avoid acting against your better judgment. You know that you should get a head start on that term paper or work project or quarterly report, but procrastination might get in your way. Your present bias, which we talked about with Angela Duckworth and Nobel laureate Richard Thaler in an earlier episode of the show, means you frequently give into temptations even when they aren’t in your long-term best interest.
Temptations are everything from procrastinating by binge watching TV instead of working on those projects to grabbing an unhealthy snack from the checkout lane at the supermarket, where you’re often pushed towards impulse buys. In general, we want to do what we know is good for us, just not right now.
A commitment device can help you ward off the immediacy of temptation, so instead of procrastinating or overindulging, you’ll have the right incentives to do what’s in your best interest. There’s a lot of fantastic research on commitment devices and how helpful they can be to people struggling to achieve important goals.
One of my favorite studies was actually done by Dean Karlan with Nava Ashraf and Wesley Yin. It focused on helping people who wanted to save more money. In the study, people were randomly assigned to either have access to a standard savings account with a standard interest rate or to have two savings options.
One option was the standard account, but the other was a commitment account. The commitment account maybe didn’t sound like a great deal. It had the same interest rate as a regular account, but it came with restrictions. You couldn’t take money out of it until a date you chose when opening it or until you reached a savings goal you set.
So this is an account that’s no better in terms of interest, but worse in terms of access to your money. The first question was would anyone even opt for the commitment account? But people of course recognized that these accounts could help them avoid the temptation to dip into savings for any little impulse that came along, and about 30% of the customers offered these accounts actually opened one.
But here’s the more impressive thing. The people randomly assigned to have access to these accounts really benefited. If you look at 100 people who didn’t have access and 100 people who did, only 30 of whom opened one, what you see is that the 100 people with access to these commitment accounts, including the 70 who declined to open one, saved a cumulative 80% more than the 100 people with only standard account offerings. So these commitment accounts worked wonders for people.
I love that study, but it’s just one of many showing how much commitment devices can help people. They’ve proven handy for achieving goals ranging from exercising more to quitting smoking to doing better in school.
I wanted to connect with someone else who’s done a lot of research in this area. Dan Ariely is a professor of psychology and behavioral economics at Duke University and a best-selling author. He joined me to talk about some of his work around procrastination, temptation, and commitment devices. Hi, Dan. Thanks so much for joining us.
Dan Ariely: My pleasure. Of course.
Katy Milkman: OK, so let me dive in by asking you a little bit about the science behind this topic. So let’s start with the question that lots of listeners will be wondering about, which is what is a commitment device? Could you define a commitment device for us?
Dan Ariely: Yeah, so a commitment device is something that makes sure that our future self will behave in the way that our current self wants them to. So Seinfeld has this skit about night guy and morning guy, and he said night guy has different goals than morning guy.
How do we make sure that the morning guy behaves accordingly to what the night guy wants him to do or the other way around? So that’s really it. It’s about making sure that our future self will do the kind of things that we want. We kind of tie their hands, and of course the story from the mythology is Ulysses and the sirens.
Katy Milkman: I’d love to talk about the science you’ve done proving that commitment devices are both effective and something that people naturally use. Could you tell me a little bit about your studies with Klaus Wertenbroch on commitment devices?
Dan Ariely: Yes. These were studies on procrastination, right? With these studies, we basically came to classes that I taught, and we said, “Look, you owe me three papers.” And one group, we said, “These papers are due at the end of the semester.” One class, we said, “These are due evenly spaced out.” Right?
But the interesting thing was the third group. In the third group, we said, “Why don’t you decide how you’re going to space it? And once you space it, you’re committing to that. You can always submit early, but if you submit late, you would lose grades for it.”
Now here’s the thing that the rational person would say. The rational person would say, “Let me commit to the last day of the class. Why should I take risk? And I’ll submit them early if I can, and if not, I’ll submit them late.”
But a person who has self-control problems and know that they have self-control problems might say, “You know what? If I delay everything to the last day, I will submit everything on the last day. I’ll start working on all of them three days before or maybe two days before the deadline. I will not have enough time and I will not perform well. So let me space them out, and sure, I’m taking a potential cost. But this potential cost will force me to behave better.”
And that’s actually what we saw. The vast majority spaced it out, and they actually got better results. The interesting thing here is that the students themselves knew that this was going to be good for them. Their intuition was that this was going to be good for them, but they needed a device to do it, because without that device, they just delayed to the last moment.
So this is basically about people being aware of their self-control and willing to take a potentially costly mechanism to get this going. We have a much more extreme version of this being tested right now. We created an app that is kind of like a Tamagotchi thing. It’s a turtle, and the turtle is happy as long as people eat well, exercise, and take their medications. And the turtle become less and less happy as people stop doing that. We know exercise from the phone. We know pill taking from an internet-enabled pill box. And what people eat, we know from them taking pictures of their food, and of course they can cheat a little bit if they want to.
We initially tested just the Tamagotchi itself—just the little turtle. And it turns out the turtle is effective, but it has very little impact. It’s great, it’s nice, but it doesn’t do enough to change health consequences.
So then the next thing we did was we gave our turtle superpowers, and the superpowers we gave the turtle is basically the ability to delete other apps from the phone. So Facebook goes away, Twitter goes away.
When we install the app, we analyze what are the apps that people use most frequently, and those are the apps that go away, that basically get deleted.
Katy Milkman: Oh, got it. If people misbehave, they’ll lose access to their favorite apps. Basically, you’re saying they pay a price for skipping out on their commitment to exercise.
Dan Ariely: People get them back every night, and they disappear every morning. Right now, we’re only doing this to people that had heart surgery. We go to people that had heart surgery and say, “Look, you just had heart surgery. You think that you’re going to go home and start exercising, and taking your medication, and eating well, but we know that that’s not going to last. Why don’t you let us install this app on your phone, and you will not be able to delete our app, but here is how this app would work, and it will force you to act better.” Most people are willing to let us install that. Indeed, it’s very effective.
Katy Milkman: That’s super interesting. I’m curious, Dan, a lot of the research on commitment devices, my read at least, has had trouble because take-up is actually often low, right? People often say, “Oh, 10% will put money in an account that they’ll have to forfeit that money if they don’t quit smoking in six months,” for instance. While it’s effective to offer that, if more than 10% took it up, it’d be much more effective. It’s really interesting that you were able to get high rates of compliance or high rates of take-up. Do you feel like there was a particular pitch you had to make to get people on board or sophisticated about the self-control problem?
Dan Ariely: I think it’s their life circumstances. After heart surgery, people are terrified, right? Heart surgery is terrifying because you don’t know when it’s coming next. People are willing to commit to a lot, I think, at that moment.
Katy Milkman: Yet, six months later, as you noted, like 40% of them are taking their meds, if I’m remembering the statistics right. It’s a shame the motivation doesn’t last.
Dan Ariely: That’s right. But that’s why, because the fear goes away.
Katy Milkman: Yeah. They acclimate, basically, and so you’re catching them at that moment when they have maximum capacity to say, “This is the most important thing,” and they aren’t acclimated.
Dan Ariely: That’s right. I think if we waited like three months after they got out of hospital, or if we took people with not as severe a problem, or people who don’t really think life needs to be changed right now, heart surgery is like a big …
Katy Milkman: Major life event.
Dan Ariely: A big step. I think people are really at a phase of being open to that.
Katy Milkman: Dan, this does raise the issue of paternalism though, right? Where do you draw the line on imposing these kinds of commitment devices on people?
Dan Ariely: It’s not as if I want to plan commitment device for everything in life. I think people should be allowed to make some mistakes. I think we don’t want everything controlled, but the question is, at what level are the mistakes people make so extreme and so large and they don’t have a chance to learn from it? Like if you don’t take your medication after a heart attack, there’s not going to be many opportunities to fix it.
Katy Milkman: Right. Right.
Dan Ariely: Or if you don’t save for retirement, there’s not going to be many chances to get better.
Katy Milkman: What are some everyday examples of useful commitment devices?
Dan Ariely: For example, I have all kinds of mechanisms to take money away from my checking account into different other accounts. I have an account for a down payment on a house, and I have an account for a down payment on my next car, and I have an account for a summer vacation. All that money goes out automatically from my checking account the day after my salary comes in. It just happens. Money, by the way, is really relatively easy to do these commitment devices, because it’s digital, and we can move it easily.
Another commitment device I’ve tried is one of those CSAs. Do you know this thing? Where you …
Katy Milkman: No. Tell me more.
Dan Ariely: These are local farmers that basically deliver a box of vegetables to your house or apartment once a week, and you commit for that for the whole year. I committed. I sadly took the big vegetable box, rather than the small one, so there was a mistake on that. But basically, Thursday, a box of vegetables shows up at my apartment. That’s a really good mechanism to basically make sure I eat more vegetables. I’ve paid for it in advance for the year, it shows up. By the way, if somebody has ideas of what to do with kale, I would love that. I live in North Carolina. We get way, way too much kale.
Katy Milkman: I’ll let you know if we get any good write-ins from that one.
Dan Ariely: I tried kale soup. I tried all kinds of things. Not an easy vegetable. I mean, I understand it’s very healthy, but … not so much that you can do. But that’s another mechanism.
Basically, if you think about it, the thing is to look at your life and see where is there a gap between what I want to do and what I’m doing. Then you can say, “OK, and what tools do I have?” By the way, calendars are another really good mechanism. I don’t know if you remember, but we had a little startup that basically scheduled things in people’s calendars. We said to people, “Tell us what you want to do.” People said, “I want to exercise, read, call my mother,” all kinds of things like that, including projects, work. We schedule it for them.
It turns out that if you put something in your calendar, not doing it is very different. If you have in your calendar, go for a walk or call your mother, not doing it is an active choice. I’m not doing it. It’s written in my calendar, 6:15, call my mother, I don’t do it, I feel very differently than “I’ll do it at some point.” So calendars also help a lot. If you have other people look at your calendar, then you get the social pressure as well. The combination of analyzing what you’re not doing well and then think about the tools to make it more likely to happen. Reward, social commitment, and so on, that’s kind of the way to go. I would start with the light ones. Then if it doesn’t work, move to heavier, more complex, more expensive mechanisms.
Katy Milkman: OK, I realize we only have like two minutes left, but I have one burning question, which is, could you do a short summary of the study that you were involved in, in South Africa with …
Dan Ariely: Discovery Health?
Katy Milkman: Yes, exactly.
Dan Ariely: Yeah. In that study, we took a very large group of people and we said, “Look, right now you’re getting 20% discount on the healthy food that you buy in the supermarket. Long story, but that’s what you get. If you are willing to commit to buy 5% more every month, you’ll keep on getting your discount. But if you don’t increase it by 5%, you lose your discount.” About a third of the people took us on this offer, which means that a third of the people is what we call sophisticated. They said, “I know that right now I buy healthy food, but I really want to buy more. And if I had a little whip that would take away my discount, maybe I will do it more.” They signed up and they ate more healthily. Now, did they always get there? No. But even on the month when they lost 20%, almost nobody wanted to get out of the program.
Katy Milkman: Dan, thank you so much. This was amazing. I really appreciate you taking the time.
Dan Ariely: Of course. With pleasure, and we’ll talk soon.
Katy Milkman: I look forward to it. OK, take care.
Dan Ariely: Bye.
Katy Milkman: Bye. Dan Ariely is the James B. Duke Professor of Psychology and Behavioral Economics at Duke University. He’s written several best-selling books that you might have heard of, including Predictably Irrational and The (Honest) Truth About Dishonesty. I’ve got links in the show notes and at schwab.com/podcast.
The tendency to sell winning stocks and hold on to losers is one of the most widely documented mistakes that investors make. On the very first episode of our sister podcast, Financial Decoder—titled “What Should You Sell?”—host Mark Riepe and his guest Omar Aguilar discuss this phenomenon and the commitment devices you can employ to help avoid it. Check it out at schwab.com/financialdecoder or wherever you listen to podcasts.
As you heard from Dean Karlan and Dan Ariely, commitment devices come in many forms. Most are less extreme than locking up your clothes or putting $10,000 on the line to lose weight, but even the simpler strategies can be effective. You’ve probably even heard of some of these before. Cutting up your credit card might help you avoid an impulse purchase. Signing up for a long-term gym membership helps you commit to going more often. And setting up automatic transfers from your paycheck to your retirement or house down-payment fund makes it much easier to save for the future. Hopefully this episode gave you some ideas about how you can beat temptation by thinking ahead, by changing the incentives you’ll face in the heat of the moment so you can stick to your goals like a hero.
That’s it for this season of Choiceology, an original podcast from Charles Schwab. We’ll be back with new episodes in the new year. Don’t forget, we have 27 episodes in our back catalog. If you’re new to the show, there’s lots of great material still to discover. Find them wherever you listen to podcasts. If you’ve enjoyed Choiceology, we’d be grateful if you’d leave us a review on Apple Podcasts so other fans can find us too. You can subscribe for free in your favorite podcasting apps. That way, you won’t miss an episode. I’m Katy Milkman. Talk to you soon.
Speaker 4: For important disclosures, see the show notes or visit schwab.com/podcast.