In a must-read book, “Explaining Social Behavior”, the author, Jon Elster, writes on pluralistic ignorance.

“I distinguished between two reasons why people at a given time might hold or profess similar beliefs: because they are influenced by similar conditions (correlation) or because they influence each other (causation). A special case of the first is provided by the many examples of simultaneous discoveries, such as the invention of the calculus by Newton and Leibniz more or less at the same time. Although no one knows exactly what the "similar conditions" were in that case, the idea may have been “in the air.” For another case of the simultaneous appearance of similar ideas consider the idea of the emperor's new clothes. Hans Christian Andersen's tale was published in 1835. In the second volume of Democracy in America, published in 1840, Tocqueville came up with a similar idea to explain the apparent stability of majority opinion:

Time, events, or individual efforts by solitary minds can in some cases ultimately undermine or gradually destroy a belief without giving any external sign that this is happening. No one combats the doomed belief openly. No forces gather to make war on it. Its proponents quietly abandon it one by one, until only a minority still clings to it. In this situation, its reign persists. Since its enemies continue to hold their peace or to communicate their thoughts only in secret, it is a long time before they can be sure that a great revolution has taken place, and, being in doubt, they make no move. They watch and keep silent. The majority no longer believes, but it still appears to believe, and this hollow ghost of public opinion is enough to chill the blood of would-be innovators and reduce them to respectful silence.

A passage from Tocqueville’s Old Regime (1856) makes a similar point about religion. In the course of the French Revolution "those who retained their old faith became afraid of being alone in their allegiance, and, dreading isolation more than heresy, joined the crowd without sharing its beliefs. So what was still only the opinion of a part of the nation came to be regarded as the opinion of all, and from then on seemed irresistible even to those who had given it this false appearance."

In these passages, Tocqueville refers to beliefs that people profess to hold (or abstain from disavowing), not to beliefs they actually and sincerely hold. In this respect his analysis differs from behavior in the moving-light experiment and in the singly public condition of the line-matching experiment. This is not, however, a hard and fast distinction. As I have argued in several places, it is not always clear what it means to "believe" that something is the case. Even in the singly public condition, the "belief" of the subjects who said that A was the matching line may have been somewhat faint. They might not, for instance, have been willing to bet money on the proposition. Also, stating a belief may, under some circumstances, induce a tendency to endorse it.

Modern psychology rediscovered Tocqueville’s insight under the heading of "pluralistic ignorance." In extreme cases, nobody believes in the truth of a certain proposition but everybody believes that everybody else believes it. In more realistic cases, most people do not believe it but believe that most people do. Both situations differ from the pathological cases in which everybody publicly professes a certain belief while knowing that nobody actually holds it in private. Communism displayed this culture of hypocrisy to an extreme degree, at least in its final gerontocratic stage. Pluralistic ignorance and cultures of hypocrisy can be sustained by the same mechanism, namely, fear of disapproval or punishment for stating deviant views. The difference is that in pluralistic ignorance, the disapproval is horizontal - meted out by fellow citizens who falsely believe they have to ostracize deviants lest they themselves be ostracized. As Tocqueville notes, nonshunners of deviants may be shunned. By contrast, the culture of hypocrisy works by vertically imposed punishment: those who do not express enthusiasm for fulfilling the plan or hatred of the class enemy are likely to lose their jobs or worse. The vertical punishment may then induce horizontal measures, if people avoid or punish deviants lest they be punished as deviants themselves.

Pluralistic ignorance also differs from the mechanism underlying the passive-bystander syndrome observed in the Kitty Genovese killing. In (a stylized version of) the latter case, each individual believed that the passivity of others justified his or her own. The cause cannot have been social pressure or a desire to conform to group norms, since the thirty-eight bystanders were too isolated from each other to form a community. Rather, the passivity seemed justified by an inference: since nobody else seemed to be doing anything, the situation could not be very serious. The "raw data" (her cries) were overwhelmed by this inference. We shall look more closely at this mechanism shortly. Here I only want to note that the situation did not involve pluralistic ignorance, since there was no discrepancy between what each person privately believed and the beliefs he or she imputed to others.

The culture of drinking has been shown to illustrate pluralistic ignorance. On many American campuses, there is a culture of heavy drinking among undergraduates, especially male. Most students do not feel comfortable with the heavy levels of drinking but go along because they believe, wrongly, that most others do." Their drinking behavior conforms to what they wrongly believe to be the typical attitude on campus rather than to their private attitudes. Another example can be taken from an experiment in which students were told to read an article written in a deliberately obtuse style that made it virtually incomprehensible, and then asked how well they had understood it and how well they thought others had understood it. In one condition, the students had the option of seeking out the experimenter and asking for assistance; in another they were expressly told they could not do so. Even in the former condition, no students went to see the experimenter because the procedure for doing so required that they risk embarrassing themselves. Each student seems to have believed, however, that whereas he or she stayed put out of fear of embarrassment, others did so because they understood the article and needed no help. Hence students in that condition tended to believe that others had understood the article better than they had themselves. The difference disappeared in the other condition. Conjecturally, this effect might be due to an "older sibling syndrome.” We are all aware of our own inner anguishes and fears, but since we do not have direct access to the inner life of others, we tend to see them as more mature and self-possessed.

In the study of drinking on campus, it was also found that over time private attitudes, beliefs about the attitudes of others, and behavior moved into line with one another, raising the question of the stability of pluralistic ignorance. There are in fact two ways in which it might disappear: by the false beliefs about others becoming true or by people ceasing to hold them. If each person adopts the belief he or she (falsely) imputed to others, that imputation would in fact become true. This would most likely happen by dissonance reduction, caused either by the discomfort of disagreeing with the majority or the discomfort of saying one thing and believing another. This seems to be what happened with drinking on campus.

On the other hand, the situation might unravel. Suppose that 20 percent of group members show in their behavior that they do not hold the belief in question, and that the remaining 80 percent pay lip service to it because they require more than 20 percent of nonconformists in the group to become nonconformists themselves. Specifically, suppose that in a group of 100, there are 20 nonconformists, 10 who would be willing to "come out" if at least 25 have already done so, 15 who would do so if at least 35 have, and 55 who would join if at least 50 have shown their true colors. As stated, the majority culture is stable. Imagine, however, that 5 of the most conformist individuals leave or die and are replaced by 5 non-conformists. In that case, the majority would unravel. The 25 nonconformists would create the conditions for 10 more to join them; the resulting 35 would attract 15 more, thus generating the requisite threshold for the remaining 50 to join. Instead of referring to the process as the unraveling of conformism, we may also see it as the snowballing of nonconformism. We shall observe a similar dynamic in collective action.

Conformism may unravel in many other ways. The little child in Andersen's tale is reflected in the line-matching experiments: when a single confederate stated the veridical opinion that D was the closest in length to B, the conformism all but disappeared. For another example, consider the widespread belief in both England and France prior to the Reformation that the king could heal scrofula by touching the sick person. The Reformation undermined this belief, since Catholics in France and Anglicans in England now were compelled to explain why the evidence in the other country was spurious. But recognizing the possibility of large-scale collective error turned out to be dangerous, since the allegedly invalid proofs used to support the belief in the other country were not very different from the ones invoked in one's own.

Another mechanism for unraveling is the publication of an opinion survey. Prior to the 1972 referendum over Norwegian entry into the Common Market (as it was called then), the government, the main political parties outside government, and the major newspapers were all massively in favor of entry. Although, as the referendum showed, there was a popular majority against entry, each individual opponent would have been led to believe himself or herself a member of a small minority had not the opinion polls indicated otherwise. Without the polls, the outcome of the referendum would in all likelihood been different. Some of those opposed to entry would have abstained from voting, since the outcome would have been seen as a foregone conclusion. Also, the movement that was formed to persuade the undecided would have remained small and uninfluential. In the period between the introduction of universal suffrage and the rise of opinion surveys, the scope for pluralistic ignorance about political matters must have been considerable.”