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Endless Propaganda: The Advertising of Public Goods, Paul Rutherford.

Influence: The Psychology of Persuasion

Chapter 4: Social Proof.

Cialdini opens this chapter--with the general theme of social pressures that encourage us to conform--with a discussion of canned laughter. No matter how much audiences claim they dislike it, the research indicates that canned laughter makes people laugh: "Experiments have found that the use of canned laughter causes an audience to laugh longer and more often when humorous material is presented and to rate the material as funnier. In addition, some evidence indicates that canned laughter is most effective for poor jokes" (115). The question is: why does it work, especially when the laugh track is often so obviously fake? To answer this question, Cialdini posits the principle of social proof: "[O]ne means we use to determine what is correct is to find out what other people think is correct...We view a behavior as more correct in a given situation to the degree that we see others performing it" (116). As with the other "weapons of influence," social proof is a shortcut that usually works well for us: if we conform to the behavior we see around us, we are less likely to make a social faux pas. The fact that canned laughter provokes an automatic response in audiences suggests that auditory cues are powerful stimuli because they influence us at a level of consciousness that is difficult to critique. (Download some Canned Laughter)

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The tendency for people to "follow suit" trades on the bandwagon fallacy and appeals especially to the psychographic profile known as believers, those who are motivated by ideals and respond well to such tag lines as "fastest growing" or "4 out of 5 doctors recommend..." (This group of consumers was previously called belongers, even more closely associating them with the principle of social proof.) The need to conform is exploited by bartenders who "salt" their tip jars, and evangelists who "seed" their audiences with ringers ready to pledge their souls to God, and their money to the church. Long line-ups outside clubs convince potential patrons that this must be where all the action is.

Bandura's research into phobias revealed that children who were afraid of dogs quickly learned to overcome their fears merely by watching another child playing happily with a dog. More significantly, children learned to overcome their fears by watching film clips of the same behavior. This technique is particularly effective when the clips show a variety of children interacting safely with the dogs. "[A]pparently the principle of social proof works best when the proof is provided by the actions of a lot of other people" (118). Imagine, then, the power of television or movies to influence the behavior of whole societies.

Saving Face

The power of belief is illustrated by the participant-observer research carried out by Festinger, Riecken and Schachter into a doomsday cult known as the Guardians, and documented in their 1956 book When Prophecy Fails. After their prediction that a flood would inundate the world and they would be carried away by spaceships did not transpire, cult members exhibited increased fervor in their beliefs. So invested were they in their beliefs that they could not risk giving them up: "The group members had gone too far, given up too much for their beliefs to see them destroyed; the shame, the economic cost, the mockery would be too great to bear" (127). In Freudian terms, their defensive behavior protected them from recognizing an unbearable truth. Cialdini explains that the moment the physical proof contradicted their beliefs, the cult members turned to the only other proof that would save them: social proof--they turned from "secretive conspirators to zealous missionaries" in an attempt to gain other converts, even though their beliefs had been shown to be baseless. "The greater the number of people who find any idea correct, the more the idea will be correct" (128). Without saying so directly, Cialdini's example of religious social proof could be considered an allegory for all the examples of millennial belief down through the ages of human civilization.

Pluralistic Ignorance

We are most vulnerable to the need for social proof when we are most uncertain, when the situation is ambiguous or unclear. When everyone in the group is uncertain and looking around for clues to appropriate behavior, the result can sometimes lead to "pluralistic ignorance." Cialdini's example is the perplexing "failure of entire groups of bystanders to aid victims in agonizing need of help" (129). The 1964 murder of Catherine Genovese, stabbed to death over a period of 35 minutes, was witnessed by at least thirty-eight neighbors, none of whom telephoned the police until after the woman was dead and silent. The media characterized the inaction of the witnesses to the murder as cold and uncaring, the result of urban alienation and apathy. Research by Latané and Darley revealed, however, that "no one had helped precisely because there were so many observers" (132). With so many people watching, the onlookers may have assumed that someone else had already contacted the police. As well, the principle of social proof determined that the witnesses would look to the others for clues about what to do. If no one else is acting, everyone else would interpret the situation as a non-emergency--a state of pluralistic ignorance. Subsequent research by Latané and Darley determined that people were less likely to receive help as the numbers of bystanders increased: "...a New York college student who appeared to be having an epileptic seizure received help 85 percent of the time when there was a single bystander present but only 31 percent of the time with five bystanders present. Cialdini concludes that the folk wisdom "safety in numbers" may often be mistaken!

The key to pluralistic ignorance is uncertainty. If someone is in need--either the victim of an attack or a medical condition--the most effective way to obtain help is to ask for it in a specific way, and direct the request to an individual. Research shows that people are very responsive when they understand that there is an emergency and their help is required. Their inaction results when they observe the inaction of others, and conclude that nothing needs to be done.


Besides uncertainty, the principle of social proof is activated by similarity: it "operates most powerfully when we are observing the behavior of people just like us" (140). This accounts, according to Cialdini, the preponderance of testimonials by "ordinary" people on television. It may, as well, account for the popularity of reality television programming: the players are not well-known stars--just people like you and I. "We will use the actions of others to decide on proper behavior for ourselves, especially when we view those others as similar to ourselves" (142). Cialdini recounts the charming story of how his son Chris learned to swim not from his father, or a lifeguard, but from another boy his own age who had already learned how. This observation has profound implications for education. To what extent do we learn from our peers rather than our instructors?

The Werther Effect

A fascinating example of social proof based on the research of David Phillips has been dubbed the "Werther effect" (after Goethe's novel The Sorrows of Young Werther.) After studying suicide statistics in the United States from 1947 to 1968, Phillips discovered that "within two months after every front-page suicide story, an average of fifty-eight more people than usual killed themselves" and that "this tendency for suicides to beget suicides occurred principally in those parts of the country where the first suicide was highly publicized and that the wider the publicity given the first suicide, the greater the number of later suicides" (146). The rash of airplane and automobile crashes is explained as an attempt by the copycat suicides--acting on the basis of social proof--to be more furtive about their purposeful death: for a variety of reasons, they engineer an accident rather than killing themselves directly, and they make sure that the accident will be lethal! So powerful is the effect of social proof, if the publicized suicide is a young person, there will be young people dying in accidents for the weeks following the story.

Similarly, publicized aggression--such as homicides or heavyweight boxing matches--have the "nasty tendency to spread to similar victims, no matter whether the aggression is inflicted on the self or on another" (151). Media coverage of suicides, homicides, and aggressive sports events are thus subject to strong ethical considerations, since the research indicates that such coverage stimulates an increased level of copycat responses. Should broadcast media publicize suicides if it is known that the principle of social proof will lead to more deaths?

Uncertainty in The Peoples Temple

Jonestown, Guyana, 1978

One of the more disturbing events illustrating the power of social conformity is the 1978 Jonestown, Guyana mass suicide orchestrated by the Reverend Jim Jones. 910 members of The Peoples Temple voluntarily drank strawberry-flavored poison at the prompting of their spiritual leader. Cialdini cites Dr. Louis Jolyon West to help explain why the charismatic Jones was able to convince over 900 people to commit mass suicide: "This wouldn't have happened in California. But they lived in total alienation from the rest of the world in a jungle situation in a hostile country" (153). Jones' followers, when they moved from San Francisco to the jungles of Guyana, found themselves engulfed in uncertainty, and, as Cialdini asserts, uncertainty animates and activates the principle of social proof. In the case of Jonestown, the followers were surrounded by similar others in an otherwise dissimilar country. In their state of uncertainty, they looked to others for signs of correct conduct, and what they saw were people like themselves taking the poison. Rev. Jim Jones' genius, according to Cialdini, lay in his understanding of social psychology: isolate a group of like individuals in an alien environment and their sense of uncertainty will turn them into a herd of followers.

Buffalo Jump

The principle of social proof acts like an automatic pilot in a plane and is usually quite useful for helping us navigate social interactions: we look around to see what others like us are doing, and we behave accordingly. We believe so we can belong. However, sometimes the data input into the automatic pilot is incorrect: sometimes the data has been purposely falsified, like canned laughter today or the use of claqueurs in the Paris opera of the early 19th century. To defend ourselves from the pressures of social proof, as soon as we find evidence of a false response, we are advised to take control away from the automatic pilot. The other common situation when social proof leads us astray is pluralistic ignorance, when a small error in judgment is magnified into something more profound, like a traffic accident that occurs because we are blindly following the actions of others. For Cialdini, the image of the buffalo jump serves as a fitting analogy to conclude the chapter on the powers of social proof as a weapon of influence. Click, whirr...jump.

Plains tribes driving buffalo to death, Alfred Miller, 1867. National Archives of Canada


VALS Types: The popular psychographic scheme developed by SRI International. Find out your psychographic classification by taking the survey.

Jonestown: Dismantling the Disinformation: by Laurie Efrein Kahalas, with the Peoples Temple for eight-and-a-half years.