with me. He said that he now understood the cause of a type of traffic accident that had always puzzled him before. The accident typically occurred on the city freeway during rush hour, when cars in all lanes were moving steadily but slowly. Events leading to the accident would start when a pair of cars, one behind the other, would simultaneously begin signaling an intention to get out of the lane they were in and into the next. Within seconds, a long line of drivers to the rear of the first two would follow suit, thinking that something—a stalled car or a construction barrier—was blocking the lane ahead. It would be in this crush to cram into the available spaces of the next lane that a collision frequently happened.
The odd thing about it all, according to the patrolman, was that very often there had been no obstruction to be avoided in the first place, and by the time of the accident, this should have been obvious to anyone who looked. He said he had more than once witnessed such accidents when there was a visibly clear road in front of the ill-fated lane switchers.
The patrolman's account provides certain insights into the way we respond to social proof. First, we seem to assume that if a lot of people are doing the same thing, they must know something we don't. Especially when we are uncertain, we are willing to place an enormous amount of trust in the collective knowledge of the crowd. Second, quite frequently the crowd is mistaken because they are not acting on the basis of any superior information but are reacting, themselves, to the principle of social proof.
So if a pair of freeway drivers decided by coincidence to change lanes at the identical moment, the next two drivers might well do the same, assuming that the forward drivers had spotted an obstruction. The resulting social evidence confronting drivers behind this group would be potent—four successive cars, all with their turn signals flashing, trying to angle into the next lane. More signal lights would go on. The social proof would be undeniable by then. For drivers to the rear, there could be no question about the correctness of switching lanes: 'All those guys ahead
There is a lesson here: An automatic-pilot device, like social proof, should never be trusted fully; even when no saboteur has fed bad information into the mechanism, it can sometimes go haywire by itself. We need to check the machine from time to time to be sure that it hasn't worked itself out of sync with the other sources of evidence in the situation—the objective facts, our prior experiences, our own judgments. Fortunately, this precaution requires neither much effort nor much time. A quick glance around is all that is needed. And this little precaution is well worth it. The consequences of single-minded reliance on social evidence can be frightening.
This aspect of the social proof phenomenon always reminds me of the way certain Indian tribes—the Blackfeet, Cree, Snake, and Crow—used to hunt the North American buffalo. There are two features of buffalo that make them especially susceptible to erroneous social evidence. First, their eyes are set in their heads so that it is easier for them to see to the side than to the front. Second, when they run, as in a stampede, it is with their heads down low so they cannot see above the herd. As a result, the Indians realized, it was possible to kill tremendous numbers of buffalo by starting a herd running toward a cliff. The animals, responding to the thundering social proof around them—and never looking up to see what lay ahead—did the rest. One astonished observer to such a hunt described the deadly outcome of the buffalo's obsessive trust in collective knowledge.
In this way, it was possible to decoy a herd toward a precipice, and cause it to plunge over en masse, the leaders being thrust overby their followers and all the rest following of their own free will.
Certainly, a flier whose plane is locked onto automatic pilot would be wise to glance occasionally at the instrument panel and out the window. In the same way, we need to look up and around periodically whenever we are locked onto the evidence of the crowd. Without this simple safeguard against misguided social proof, our prospects might well run parallel to those of the freeway lane switchers and the North American buffalo: Crash.
READER'S REPORT
From a Former Racetrack Employee
'I became aware of one method of faking social evidence to one's advantage while working at a racetrack. In order to lower the odds and make more money, some bettors are able to sway the public to bet on bad horses.
'Odds at a racetrack are based on where the money is being bet. The more money on a horse, the lower (better) the odds. Many people who play the horses have surprisingly little knowledge of racing or betting strategy. Thus, especially when they don't know much about the horses in a particular race, a lot of times they'll simply bet the favorite. Because tote boards are displayed with up-to-the-minute odds, the public can always tell who the current favorite is. The system that a high roller can use to alter the odds is actually quite simple. The guy has in mind a horse he feels has a good chance of winning. Next he chooses a horse that has long odds (say, 15 to 1) and doesn't have a realistic chance to win. The minute the mutual windows open, the guy puts down a hundred dollars on the inferior horse, creating an instant favorite whose odds on the board drop to about 2 to 1.
'Now the elements of social proof begin to work. People who are uncertain of how to bet the race look to the tote board to see which horse the early bettors have decided is a favorite, and they follow. A snowballing effect now occurs as other people continue to bet the favorite. At this point, the high roller can go back to the window and bet heavily on his true favorite, which will have better odds now because the 'new favorite' has pushed down the board. If the guy wins, the initial hundred-dollar investment will have been worth it many times over. 'I've seen this happen myself. I remember one time a person put down a hundred dollars on a prerace 10-to-1 shot, making it the early favorite. The rumors started circulating around the track—people knew something. Next thing you know, everyone (me included) was betting on this horse. It ended up running last and had a bad leg. Many people lost a lot of money. Somebody came out ahead though. We'll never know who. But he is the one with all the money. He understood the theory of social proof.'
The Friendly Thief
—Clarence Darrow
FEW PEOPLE WOULD BE SURPRISED TO LEARN THAT, AS A RULE, we most prefer to say yes to the requests of someone we know and like. What might be startling to note, however, is that this simple rule is used in hundreds of ways by total strangers to get us to comply with
The clearest illustration I know of the professional exploitation of the liking rule is the Tupperware party, which I consider the quintessential American compliance setting. Anybody familiar with the workings of a Tupperware party will recognize the use of the various weapons of influence we have examined so far: reciprocity (to start, games are played and prizes won by the partygoers; anyone who doesn't win a prize gets to reach into a grab bag for hers so that everyone has received a gift before the buying begins), commitment (each participant is urged to describe publicly the uses and benefits she has found in the Tupper-ware she already owns), and social proof (once the buying begins, each purchase builds the idea that other, similar people want the product; therefore, it must be good).
All the major weapons of influence are present to help things along, but the real power of the Tupperware party comes from a particular arrangement that trades on the liking rule. Despite the entertaining and persuasive salesmanship of the Tupperware demonstrator, the true request to purchase the product does not come from this stranger; it comes from a friend to every woman in the room. Oh, the Tupperware representative may physically ask for each partygoer's order, all right, but the more psychologically compelling requester is a housewife sitting off to the side, smiling, chatting, and serving refreshments. She is the party hostess, who has called her friends
