Read Predictably Irrational Online
Authors: Dr. Dan Ariely
In all these conflicts, individuals from both sides can read similar history books and even have the same facts taught to them, yet it is very unusual to find individuals who would agree about who started the conflict, who is to blame, who should make the next concession, etc. In such matters, our investment in our beliefs is much stronger than any affiliation to sport teams, and so we hold on to these beliefs tenaciously. Thus the likelihood of agreement about “the facts” becomes smaller and smaller as personal investment in the problem grows. This is clearly disturbing. We like to think that sitting at the same table together will help us hammer out our differences and that concessions will soon follow. But history has shown us that this is an unlikely outcome; and now we know the reason for this catastrophic failure.
But there's reason for hope. In our experiments, tasting beer without knowing about the vinegar, or learning about the vinegar after the beer was tasted, allowed the true flavor to come out. The same approach should be used to settle arguments: The perspective of each side is presented without the affiliationâthe facts are revealed, but not which party took which actions. This type of “blind” condition might help us better recognize the truth.
When stripping away our preconceptions and our previous knowledge is not possible, perhaps we can at least acknowledge that we are all biased. If we acknowledge that we are trapped within our perspective, which partially blinds us to the truth, we may be able to accept the idea that conflicts generally require a neutral third partyâwho has not been tainted with our expectationsâto set down the rules and regulations. Of course, accepting the word of a third party is not easy and not always possible; but when it is possible, it can yield substantial benefits. And for that reason alone, we must continue to try.
Reflections on Expectations: Music and Food
Imagine walking into a truck stop off a deserted stretch of Interstate 95 at nine o'clock in the evening. You've been driving for six hours. You are tired and still have a long drive ahead of you. You need a bite to eat and want to be out of the car for a bit, so you walk into what appears to be a restaurant of sorts. It has the usual cracked-vinyl-covered booths and fluorescent lighting. The coffee-stained tabletops leave you a bit wary. Still, you think, “Fine, no one can screw up a hamburger that badly.” You reach for the menu, conveniently stashed behind an empty napkin dispenser, only to discover this is no ordinary greasy spoon. Instead of hamburgers and chicken sandwiches, you're astonished to see that the menu offers foie gras au torchon, truffle pâté with frisée and fennel marmalade, gougères with duck confit, quail à la crapaudine, and so on.
Items like this would be no surprise in even a small Manhattan restaurant, of course. And it is possible that the chef got tired of Manhattan, moved to the middle of nowhere, and now cooks for whoever happens through. So is there a key difference between ordering gougères with duck confit in Manhattan and ordering it at an isolated truck stop on I-95? If you encountered such French delicacies at the truck stop, would you be brave enough to try them? Suppose the prices were not listed on the menu. What would you be willing to pay for an appetizer or an entrée? And if you ate it, would you enjoy it as much as you might if you were eating the same food in Manhattan?
On the basis of what we learned from Chapter 10, the answers are simple. Ambience and expectations do add a great deal to our enjoyment. You would expect less in such an environment, and as a consequence you would enjoy the experience at the truck stop less, even if you had the identical foie gras au torchon in both places. Likewise, if you knew that pâté is largely made of run-of-the-mill goose liver and butter
*
rather than super special ingredients, you would enjoy it much less.
A
FEW YEARS
ago the folks at the
Washington Post
were curious about the same basic topic and decided to run an experiment.
11
Instead of food, they used music. The experimental question was this: can outstanding art shine through a filter of mundane and dingy expectation?
Journalist Gene Weingarten asked Joshua Bell, generally considered one of the best violinists in the world, to pose as a street performer and play some of the finest music ever composed
*
at a Metro station in Washington, D.C., during the morning rush hour. Would people notice that this guy was better than most buskers? Would they stop to listen? Would they throw a dollar or two his way? Would you?
If you were like 98 percent of the people who passed through L'Enfant Plaza Station that morning, you would have hurried by, oblivious of the performance. Only 27 out of 1,097 (2.5 percent) put money into Bell's open Stradivarius violin case and only 7 (0.5 percent) stopped to listen for more than a minute. Bell played for a little less than an hour and made about $32, which is probably not bad for your basic street performer, but no doubt humbling to a man used to making far, far more for one minute of playing.
Weingarten interviewed a number of people who passed through the station that morning. Of the people who stopped, one recognized Bell from a performance the night before. Another was a serious violinist himself. Another was a Metro worker who, after years of listening to ordinary, albeit occasionally talented, buskers, discerned that Bell was better than average. Aside from these fewâand disturbingly to classical music fans, and Bell's fans in particularâpeople did not stop to listen. Many didn't even look at Bell. When interviewed, passersby said either that they didn't notice the music at all, or that it sounded like a slightly better than average street performer playing everyday classical music. No one expected a world-class musician to be playing technically dazzling pieces in a Metro station. Accordingly, and for the most part, they didn't hear one.
Sometime later I met Joshua Bell and asked him about this experience. In particular, I wanted to know how he felt about being overlooked and ignored by so many people. He responded that he was really not all that surprised, and admitted that expectation is an important part of the way we experience music. Bell told me that it takes an appropriate setting to help people appreciate a live classical music performanceâa listener needs to be sitting in a comfortable, faux velvet seat, and surrounded by the acoustics of a concert hall. And when people adorn themselves in silk, perfume, and cashmere, they seem to appreciate the costly performance much more.
“What if we did the opposite experiment?” I asked. “What if we put a mediocre player in Carnegie Hall with the Berlin Philharmonic? The expectations would be very high but the quality would not. Would people discern the difference and would their pleasure be quashed?” Bell thought for a moment. “In this case,” he said, “the expectations would triumph over the experience.” Furthermore, he said he could think of a few people who were not great violinists but received wild applause because they were in the right environment.
In the end, I wasn't convinced by Bell's nonchalance about his Metro performance. After all, time heals all wounds, and one of the ways time works in our favor is to help us either forget or misremember the past in a way that makes us feel better about ourselves. Besides, not being surprised that people were too busy to notice his performance must have helped Bell avoid the violinist's version of the old question: “If a tree falls in the forest, and no one is around to hear it, does it make a sound?”
The following day, sitting in the Monterey auditorium, I had the opportunity to listen to Joshua Bell play Bach's famous “Chaconne”âthe same wonderful piece that he had played for his commuter audience. I closed my eyes and imagined that, instead of listening to a great violinist, I was hearing a mediocre fifteen-year-old kid play a Stradivarius. I'm no connoisseur, but I swear I could hear a few off-key patches, and some squeaks of the strings suddenly became audible. Perhaps the squeaks were part of Bach's composition, just an inevitable part of playing a stringed instrument, or maybe they were a result of playing in an auditorium rather than a proper concert hall. I could easily imagine how an untrained listener such as myself might attribute these sounds to mistakes of a mediocre player, especially if the player is standing in a bustling train station during rush hour.
At the end of his performance, Bell got a long standing ovation. Though I had enjoyed the performance, I wondered how much the ovation was a reward for his performance and how much was due to the audience's expectations. I'm not questioning the level of Bell's (or anyone's) talent. The point is that we don't really understand the role expectations play in the way we experience and evaluate art, literature, drama, architecture, food, wineâanything, really.
I THINK THAT
the role of expectations may have been captured best by one of my favorite authors. In Jerome K. Jerome's 1889 comic novella
Three Men in a Boat
, the narrator and his two traveling companions are at a party at an inn. The discussion happens to turn to comic songs. Two young men, outsiders who lack the aristocratic manners of the other partygoers, assure them that a song by the renowned German comic Herr Slossenn Boschen is the funniest of all, and that Herr Boschen happens to be staying at the very same inn. Perhaps he might be persuaded to play one of his songs for them?
Herr Boschen is quite glad to play for them, and since only the two young men understand German, though everyone else pretends to understand it, the rest of the audience take their cues from them. As the two young men shriek with laughter, so do they. Some members of the audience go a step further and from time to time laugh on their own, pretending to have understood a bit of subtle humor missed by the others.
In reality, it turns out that Herr Boschen is a renowned tragedian and is doing his best to deliver a dramatic, emotionally laden songâwhile the two young men laugh every few notes in order to fool the rest of the guests into believing that such is the style of German comedy. Confused, Herr Boschen presses on. But when he finishes singing, he leaps up from the piano and pours a stream of German obscenities over his listeners.
Ignorant of German and Germany's musical conventions, the audience members do the next best thing and follow the purported expertise of the two outsiders, laugh on cue from them, and believe that the whole performance, including Boschen's temper tantrum, is uproariously funny. Overall the audience enjoys the performance a great deal.
Jerome's story is exaggerated, but in truth, this is how most of us navigate the world. Across many domains of life, expectations play a huge role in the way we end up experiencing things. Think about the
Mona Lisa
. Why is this portrait so beautiful, and why is the woman's smile mysterious? Can you discern the technique and talent it took for Leonardo da Vinci to create it? For most of us the painting is beautiful, and the smile mysterious, because we are told it is so. In the absence of expertise or perfect information, we look for social cues to help us figure out how much we are, or should be, impressed, and our expectations take care of the rest.
T
HE BRILLIANT SATIRIST
Alexander Pope once wrote: “Blessed is he who expects nothing, for he shall never be disappointed.” To me, it seems that Pope's advice is the best way to live an objective life. Clearly, it is also very helpful in eliminating the effects of negative expectations. But what about positive expectations? If I listen to Joshua Bell with no expectations, the experience is not going to be nearly as satisfying or pleasurable as if I listen to him and say to myself, “My god, how lucky I am to be listening to Joshua Bell play live in front of me.” My knowledge that Bell is one of the best players in the world contributes immeasurably to my pleasure.
As it turns out, positive expectations allow us to enjoy things more and improve our perception of the world around us. The danger of expecting nothing is that, in the end, it might be all we'll get.
I
f you were living in 1950 and had chest pain, your cardiologist might well have suggested a procedure for angina pectoris called internal mammary artery ligation. In this operation, the patient is anesthetized, the chest is opened at the sternum, and the internal mammary artery is tied off. Voilà ! Pressure to the pericardiophrenic arteries is raised, blood flow to the myocardium is improved, and everyone goes home happy.
12
This was an apparently successful operation, and it had been a popular one for the previous 20 years. But one day in 1955, a cardiologist in Seattle, Leonard Cobb, and a few colleagues became suspicious. Was it really an effective procedure? Did it really work? Cobb decided to try to prove the efficacy of the procedure in a very bold way: he would perform the operation on half his patients, and fake the procedure on the other half. Then he would see which group felt better, and whose health actually improved. In other words, after 25 years of filleting patients like fish, heart surgeons would finally get a scientifically controlled surgical trial to see how effective the procedure really was.
To carry out this test, Dr. Cobb performed the traditional procedure on some of the patients, and placebo surgery on the others. The real surgery meant opening the patient up and tying up the internal mammary artery. In the placebo procedure, the surgeon merely cut into the patient's flesh with a scalpel, leaving two incisions. Nothing else was done.
The results were startling. Both the patients who did have their mammary arteries constricted and those who didn't reported immediate relief from their chest pain. In both groups, the relief lasted about three monthsâand then complaints about chest pain returned. Meanwhile, electrocardiograms showed no difference between those who had undergone the real operation and those who got the placebo operation. In other words, the traditional procedure seemed to provide some short-term reliefâbut so did the placebo. In the end, neither procedure provided significant long-term relief.
More recently a different medical procedure was submitted to a similar test, with surprisingly similar results. As early as 1993, J. B. Moseley, an orthopedic surgeon, had increasing doubts about the use of arthroscopic surgery for a particular arthritic affliction of the knee. Did the procedure really work? Recruiting 180 patients with osteoarthritis from the veterans' hospital in Houston, Texas, Dr. Moseley and his colleagues divided them into three groups.
One group got the standard treatment: anesthetic, three incisions, scopes inserted, cartilage removed, correction of soft-tissue problems, and 10 liters of saline washed through the knee. The second group got anesthesia, three incisions, scopes inserted, and 10 liters of saline, but no cartilage was removed. The third groupâthe placebo groupâlooked from the outside like the other two treatments (anesthesia, incisions, etc.); and the procedure took the same amount of time; but no instruments were inserted into the knee. In other words, this was simulated surgery.
13
For two years following the surgeries, all three groups (which consisted of volunteers, as in any other placebo experiment) were tested for a lessening of their pain, and for the amount of time it took them to walk and climb stairs. How did they do? The groups that had the full surgery and the arthroscopic lavage were delighted, and said they would recommend the surgery to their families and friends. But strangelyâand here was the bombshellâthe placebo group also got relief from pain and improvements in walkingâto the same extent, in fact, as those who had the actual operations. Reacting to this startling conclusion, Dr. Nelda Wray, one of the authors of the Moseley study, noted, “The fact that the effectiveness of arthroscopic lavage and debridement in patients with osteoarthritis of the knee is no greater than that of placebo surgery makes us question whether the $1 billion spent on these procedures might be put to better use.”
If you assume that a firestorm must have followed this report, you're right. When the study appeared on July 11, 2002, as the lead article in the
New England Journal of Medicine
, some doctors screamed foul and questioned the method and results of the study. In response, Dr. Moseley argued that his study had been carefully designed and carried out. “Surgeons . . . who routinely perform arthroscopy are undoubtedly embarrassed at the prospect that the placebo effectânot surgical skillâis responsible for patient improvement after the surgeries they perform. As you might imagine, these surgeons are going to great lengths to try to discredit our study.”
Regardless of the extent to which you believe the results of this study, it is clear that we should be more suspicious about arthroscopic surgery for this particular condition, and at the same time increase the burden of proof for medical procedures in general.
I
N THE PREVIOUS
chapter we
saw that expectations change the way we perceive and appreciate experiences. Exploring the placebo effect in this chapter, we'll see not only that beliefs and expectations affect how we perceive and interpret sights, tastes, and other sensory phenomena, but also that our expectations can affect us by altering our subjective and even objective experiencesâsometimes profoundly so.
Most important, I want to probe an aspect of placebos that is not yet fully understood. It is the role that
price
plays in this phenomenon. Does a pricey medicine make us feel better than a cheap medicine? Can it actually make us
physiologically
better than a cheaper brand? What about expensive procedures, and new-generation apparatuses, such as digital pacemakers and high-tech stents? Does their price influence their efficacy? And if so, does this mean that the bill for health care in America will continue to soar? Well, let's start at the beginning.
P
LACEBO
COMES FROM
the Latin for “I shall please.” The term was used in the fourteenth century to refer to sham mourners who were hired to wail and sob for the deceased at funerals. By 1785 it appeared in the
New Medical Dictionary
, attached to marginal practices of medicine.
One of the earliest recorded examples of the placebo effect in medical literature dates from 1794. An Italian physician named Gerbi made an odd discovery: when he rubbed the secretions of a certain type of worm on an aching tooth, the pain went away for a year. Gerbi went on to treat hundreds of patients with the worm secretions, keeping meticulous records of their reactions. Of his patients, 68 percent reported that their pain, too, went away for a year. We don't know the full story of Gerbi and his worm secretions, but we have a pretty good idea that the secretions really had nothing to do with curing toothaches. The point is that Gerbi believed they helpedâand so did a majority of his patients.
Of course, Gerbi's worm secretion wasn't the only placebo in the market. Before recent times, almost all medicines were placebos. Eye of the toad, wing of the bat, dried fox lungs, mercury, mineral water, cocaine, an electric current: these were all touted as suitable cures for various ailments. When Lincoln lay dying across the street from Ford's Theater, it is said that his physician applied a bit of “mummy paint” to the wounds. Egyptian mummy, ground to a powder, was believed to be a remedy for epilepsy, abscesses, rashes, fractures, paralysis, migraine, ulcers, and many other things. As late as 1908, “genuine Egyptian mummy” could be ordered through the E. Merck catalogâand it's probably still in use somewhere today.
14
Mummy powder wasn't the most macabre of medicines, though. One seventeenth-century recipe for a “cure all” medication advised: “Take the fresh corpse of a red-haired, uninjured, unblemished man, 24 years old and killed no more than one day before, preferably by hanging, breaking on the wheel or impaling. . . . Leave it one day and one night in the light of the sun and the moon, then cut into shreds or rough strips. Sprinkle on a little powder of myrrh and aloes, to prevent it from being too bitter.”
We may think we're different now. But we're not. Placebos still work their magic on us. For years, surgeons cut remnants of scar tissue out of the abdomen, for instance, imagining that this procedure addressed chronic abdominal painâuntil researchers faked the procedure in controlled studies and patients reported equal relief.
15
Encainide, flecainide, and mexiletine were widely prescribed off-label drugs for irregular heartbeatâand were later found to cause cardiac arrest.
16
When researchers tested the effect of the six leading antidepressants, they noted that 75 percent of the effect was duplicated in placebo controls.
17
The same was true of brain surgery for Parkinson's disease.
18
When physicians drilled holes in the skulls of several patients without performing the full procedure, to test its efficacy, the patients who received the sham surgery had the same outcome as those who received the full procedure. And of course the list goes on and on.
One could defend these modern procedures and compounds by noting that they were developed with the best intentions. This is true. But so were the applications of Egyptian mummy, to a great extent. And sometimes, the mummy powder worked just as well as (or at least no worse than) whatever else was used.
The truth is that placebos run on the power of suggestion. They are effective because people believe in them. You see your doctor and you feel better. You pop a pill and you feel better. And if your doctor is a highly acclaimed specialist, or your prescription is for a new wonder drug of some kind, you feel even better. But how does suggestion influence us?
I
N GENERAL, TWO
mechanisms shape the expectations that make placebos work. One is beliefâour confidence or faith in the drug, the procedure, or the caregiver. Sometimes just the fact that a doctor or nurse is paying attention to us and reassuring us not only makes us feel better but also triggers our internal healing processes. Even a doctor's enthusiasm for a particular treatment or procedure may predispose us toward a positive outcome.
The second mechanism is conditioning. Like Pavlov's famous dogs (that learned to salivate at the ring of a bell), the body builds up expectancy after repeated experiences and releases various chemicals to prepare us for the future. Suppose you've ordered pizza night after night. When the deliveryman presses the doorbell, your digestive juices start flowing even before you can smell the pie. Or suppose that you are snuggled up on the couch with your loved one. As you're sitting there staring into a crackling fire, the prospect of sex releases endorphins, preparing you for what is to come next, and sending your sense of well-being into the stratosphere.
In the case of pain, expectation can unleash hormones and neurotransmitters, such as endorphins and opiates, that not only block agony but produce exuberant highs (endorphins trigger the same receptors as morphine). I vividly recall lying in the burn ward in terrible pain. As soon as I saw the nurse approaching, with a needle almost dripping with painkiller, what relief! My brain began secreting pain-dulling opioids, even before the needle broke my skin.
Thus familiarity may or may not breed contempt, but it definitely breeds expectations. Branding, packaging, and the reassurance of the caregiver can make us feel better. But what about price? Can the price of a drug also affect our response to it?
O
N THE BASIS
of price alone, it is easy to imagine that a $4,000 couch will be more comfortable than a $400 couch; that a pair of designer jeans will be better stitched and more comfortable than a pair from Wal-Mart; that a high-grade electric sander will work better than a low-grade sander; and that the roast duck at the Imperial Dynasty (for $19.95) is substantially better than the roast duck at Wong's Noodle Shop (for $10.95). But can such implied difference in quality influence the actual experience, and can such influence also apply to objective experiences such as our reactions to pharmaceuticals?
For instance, would a cheaper painkiller be less effective than a more expensive one? Would your winter cold feel worse if you took a discount cold medicine than if you took an expensive one? Would your asthma respond less well to a generic drug than to the latest brand-name on the market? In other words, are drugs like Chinese food, sofas, blue jeans, and tools? Can we assume that high price means higher quality, and do our expectations translate into the objective efficacy of the product?
This is a particularly important question. The fact is that you can get away with cheaper Chinese food and less expensive jeans. With some self-control, we can usually steer ourselves away from the most expensive brands. But will you really look for bargains when it comes to your health? Putting the common cold aside for the moment, are many of us going to pinch pennies when our lives are at risk? Noâwe want the best, for ourselves, our children, and our loved ones.
If we want the best for ourselves, does an expensive drug make us feel better than a cheaper drug? Does cost really make a difference in how we feel? In a series of experiments a few years ago, that's what Rebecca Waber (a graduate student at MIT), Baba Shiv (a professor at Stanford), Ziv Carmon, and I decided to find out.
I
MAGINE THAT YOU'RE
taking part in an experiment to test the efficacy of a new painkiller called Veladone-Rx. (The actual experiment involved about 100 adult Bostonians, but for now, we'll let you take their place.)
You arrive at the MIT Media Lab in the morning. Taya Leary, a young woman wearing a crisp business suit (this is in stark contrast to the usual attire of the students and faculty at MIT), greets you warmly, with a hint of a Russian accent. A photo ID identifies Taya as a representative of Vel Pharmaceuticals. She invites you to spend a moment reading a brochure about Veladone-Rx. Glancing around, you note that the room looks like a medical office: stale copies of
Time
and
Newsweek
are scattered around; brochures for Veladone-Rx are spread out on the table; and nearby is a cup of pens, with the drug's handsome logo. “Veladone is an exciting new medication in the opioid family,” you read. “Clinical studies show that over 92 percent of patients receiving Veladone in double-blind controlled studies reported significant pain relief within only 10 minutes, and that pain relief lasted up to eight hours.” And how much does it cost? According to the brochure, $2.50 for a single dose.