Fragmentation and Cybercascades

by Cass Sunstein

he term group polarization refers to something very simple: After deliberation people are likely to move toward a more extreme point in the direction to which the group's members were originally inclined. With respect to the Internet and new communications technologies, the implication is that groups of like-minded people, engaged in discussion with one another, will end up thinking the same thing that they thought before--but in more extreme form.

Consider some examples of the basic phenomenon, which has been found in over a dozen nations (Brown, 222).

The phenomenon of group polarization has conspicuous importance to the communications market, where groups with distinctive identities increasingly engage in within-group discussion. Effects of the kind just described should be expected with the Unorganized Militia and racial hate groups as well as with less extreme organizations of all sorts. If the public is balkanized and if different groups are designing their own preferred communications packages, the consequence will be not merely the same but still more balkanization, as group members move one another toward more extreme points in line with their initial tendencies. At the same time, different deliberating groups, each consisting of like-minded people, will be driven increasingly far apart, simply because most of their discussions are with one another.

Note in particular that even if most of us do not use the power to filter so as to wall ourselves off from other points of view, some or many people will do, and are doing, exactly that.

This is sufficient for polarization to occur, and to cause serious social risks. In general, it is precisely the people most likely to filter out opposing views who most need to hear such views. New technologies, emphatically including the Internet, make it easier for people to hear the opinions of like-minded but otherwise isolated others, and to isolate themselves from competing views. For this reason alone, they are a breeding ground for polarization, and potentially dangerous for both democracy and social peace.

There have been two main explanations for group polarization. Massive evidence now supports both these explanations.

The first explanation emphasizes the role of persuasive arguments. It is based on a simple intuition: Any individual's position on any issue is a function, at least in part, of which arguments seem convincing. If your position is going to move as a result of group discussion, it is likely to move in the direction of the most persuasive position defended within the group, taken as a whole.

If the group's members are already inclined in a certain direction, they will offer a disproportionately large number of arguments going in that same direction, and a disproportionately small number of arguments going the other way. As a result, the consequence of discussion will be to move people further in the direction of their initial inclinations. Thus, for example, a group whose members lean against gun control will, in discussion, provide a wide range of arguments against gun control, and the arguments made for gun control will be both fewer and weaker. The group's members, to the extent that they shift, will shift toward a more extreme position against gun control. And the group as a whole, if a group decision is required, will move not to the median position, but to a more extreme point.

On this account, the central factor behind group polarization is the existence of a limited argument pool--one that is skewed (speaking purely descriptively) in a particular direction. It is easy to see how shifts might happen with discussion groups on the Internet (consider a group of Democrats, or Socialists, or members of the Unorganized Militia), and indeed with individuals not engaged in discussion but consulting only ideas (on radio, television, or the World Wide Web) to which they are antecedently inclined. The tendency of such discussion groups, and such consultations, will be to entrench and reinforce preexisting positions--often resulting in extremism.

The second mechanism, involving social comparison, begins with the reasonable suggestion that people want to be perceived favorably by other group members, and also to perceive themselves favorably. Once they hear what others believe, they often adjust their positions in the direction of the dominant position.

Suppose, for example, that people in a certain group believe that they are sharply opposed to affirmative action, feminism and gun control, and that they also want to seem to be sharply opposed to all these. If they are in a group whose members are also sharply opposed to these things, they might well shift in the direction of even sharper opposition after they see what other group members think. In countless studies, exactly this pattern is observed. Of course people will not shift if they have a clear sense of what they think and are not movable by the opinions of others. But most people, most of the time, are not so fixed in their views.

The point has important implications about the effects of exposure to ideas and claims on television, radio and the Internet--even in the absence of a chance for interaction. Because group polarization occurs merely on the basis of exposure to the views of others, it is likely to be a common phenomenon in a balkanized speech market. Suppose, for example, that conservatives are visiting conservative Websites; that liberals are visiting liberal Websites; that environmentalists are visiting sites dedicated to establishing the risks of genetic engineering and global warming; that critics of environmentalists are visiting sites dedicated to exposing frauds allegedly perpetrated by environmentalists; that people inclined to racial hatred are visiting sites that express racial hatred. To the extent that these exposures are not complemented by exposure to competing views, group polarization will be the inevitable consequence.

Fragmentation, polarization, radio and television

An understanding of group polarization casts light on the potential effects not only of the Internet but also of radio and television, at least if stations are numerous and many take a well-defined point of view. Recall that mere exposure to the positions of others creates group polarization. It follows that this effect will be at work for nondeliberating groups, in the form of collections of individuals whose communications choices go in the same direction, and who do not expose themselves to alternative positions. Indeed the same process is likely to occur for newspaper choices. General interest intermediaries have a distinctive role here, by virtue of their effort to present a wide range of topics and views. Polarization is far less likely to occur when such intermediaries dominate the scene. A similar point can be made about the public forum doctrine. When diverse speakers have access to a heterogeneous public, individuals and groups are less likely to be able to insulate themselves from competing positions and concerns. Fragmentation is correspondingly less likely.

Group polarization also raises more general issues about communications policy. Consider the "fairness doctrine," now largely abandoned but once requiring radio and television broadcasters to devote time to public issues and to allow an opportunity for those with opposing views to speak. The latter prong of the doctrine was designed to ensure that listeners would not be exposed to any single view--if one view was covered, the opposing position would have to be allowed a right of access. When the Federal Communications Commission abandoned the fairness doctrine, it did so on the ground that this second prong led broadcasters, much of the time, to avoid controversial issues entirely, and to present views in a way that suggested a bland uniformity. Subsequent research has suggested that the elimination of the fairness doctrine has indeed produced a flowering of controversial substantive programming, frequently expressing extreme views of one kind or another; consider talk radio (Hazlett and Sosa, 279).

Typically this is regarded as a story of wonderfully successful deregulation. The effects of eliminating the fairness doctrine were precisely what was sought and intended. But from the standpoint of group polarization, the evaluation is far more complicated. On the good side, the existence of diverse pockets of opinion would seem to enrich society's total argument pool, potentially to the benefit of all of us. At the same time, the growth of a wide variety of issues-oriented programming--expressing strong, often extreme views, and appealing to dramatically different groups of listeners and viewers--is likely to create group polarization. All too many people are now exposed largely to louder echoes of their own voices, resulting, on occasion, in misunderstanding and enmity. Perhaps it is better for people to hear fewer controversial views than for them to hear a single such view, stated over and over again. At least there is a risk, in the current situation, that too many people will be insulated from exposure to views that are more moderate, or extreme in another direction, or in any case different from their own.

Is group polarization bad? Of enclave deliberation

Of course we cannot say, from the mere fact of group polarization, that there has been a movement in the wrong direction. Notwithstanding some of the grotesque examples given here, the more extreme tendency might be better rather than worse. Indeed, group polarization helped fuel many movements of great value--including, for example, the civil rights movement, the antislavery movement, and the movement for sex equality. Each of these movements was extreme in its time, and within-group discussion certainly bred greater extremism; but extremism should not be a word of opprobrium. If greater communications choices produce greater extremism, society may, in many cases, be better off as a result. One reason is that when many different groups are deliberating with one another, society will hear a far wider range of views as a result. Even if the "information diet" of many individuals is homogeneous or insufficiently diverse, society as a whole might have a more richer and fuller set of ideas. This is another side of the general picture of social fragmentation. It suggests some large benefits from pluralism and diversity--benefits even if individuals customize and cluster in groups.

We might define enclave deliberation as that form of deliberation that occurs within more or less insulated groups, in which like-minded people speak mostly to one another. The Internet, along with other new communications options, makes it much easier to engage in enclave deliberation. It is obvious that enclave deliberation can be extremely important in a heterogeneous society, not least because members of some groups tend to be especially quiet when participating in broader deliberative bodies. In this light, a special advantage of enclave deliberation is that it promotes the development of positions that would otherwise be invisible, silenced, or squelched in general debate.

The central empirical point here is that in deliberating bodies, high-status members tend to speak more than others, and their ideas are more influential--partly because low-status members lack confidence in their own abilities, and partly because they fear retribution (Christenson and Abbott, 273-76). For example, women's ideas are often less influential and sometimes are "suppressed altogether in mixed-gender groups," (Christenson and Abbott, 274) and in ordinary circumstances, cultural minorities have disproportionately little influence on decisions by culturally mixed groups. In light of the inevitable existence of some status-based hierarchies, it makes sense to be receptive to deliberating enclaves in which members of multiple groups may speak with one another and develop their views. The Internet is and will continue to be particularly valuable insofar as it makes this easier.

But there is also a serious danger in such enclaves. The danger is that through the mechanisms of social influence and persuasive arguments, members will move to positions that lack merit but are predictable consequences of the particular circumstances of enclave deliberation. In the extreme case, enclave deliberation may even put social stability at risk.

Enclaves and a public sphere

Whenever group discussion tends to lead people to more strongly held versions of the same view with which they began, there is legitimate reason for concern. This does not mean that the discussions can or should be regulated. But it does raise questions about the idea that "more speech" is necessarily an adequate remedy for bad speech--especially if many people are inclined and increasingly able to wall themselves off from competing views. In democratic societies, the best response is suggested by the public forum doctrine, whose most fundamental goal is to increase the likelihood that at certain points, there is an exchange of views between enclave members and those who disagree with them. It is total or near-total self-insulation, rather than group deliberation as such, that carries with it the most serious dangers, often in the highly unfortunate (and sometimes literally deadly) combination of extremism with marginality.

To explore some of the advantage of heterogeneity, let us engage in a thought experiment. Imagine a deliberating body consisting not of a subset of like-minded people but of all citizens in the relevant group; this may mean all citizens in a community, a state, a nation, even the world. Imagine that through the magic of the computer, everyone can talk to everyone else. By hypothesis, the argument pool would be very large. It would be limited only to the extent that the set of citizen views was similarly limited. Of course social influences would remain. If you are one of a small minority of people who deny that global warming is a serious problem, you might decide to join the crowd. But when deliberation reveals to people that their private position is different, in relation to the group, from what they thought it was, any shift would be in response to an accurate understanding of all relevant citizens, and not a product of a skewed sample.

This thought experiment does not suggest that a fragmented or balkanized speech market is always bad or that the hypothesized, all-inclusive deliberating body would be ideal. It would be foolish to suggest that all discussion should occur, even as an ideal, with all others. The great benefit of deliberating enclaves is that positions may emerge that otherwise would not, and that deserve to play a larger role both within the enclave and within the heterogeneous public. Properly understood, the case for deliberating enclaves is that they will improve social deliberation, democratic and otherwise, precisely because enclave deliberation is often required for incubating new ideas and perspectives that will add a great deal to public debate. But for these improvements to occur, members must not insulate themselves from competing positions, or at least any such attempts at insulation must not be a prolonged affair. The effects of group polarization thus show that with respect to communications, consumer sovereignty might well produce serious problems for individuals and society at large--and these problems will occur by a kind of iron logic of social interactions.

Cybercascades: Information as wildfire, and tipping points

The phenomenon of group polarization is closely related to the widespread phenomenon of social cascades. No discussion of social fragmentation and emerging communications technologies would be complete without an understanding of cascades--above all because they become more likely when information, including false information, can be spread to hundreds, thousands, or even millions by the simple press of a button.

It is obvious that many social groups, both large and small, move rapidly and dramatically in the direction of one or another set of beliefs or actions (Bikhchandani et al., 158). These sorts of cascades typically involve the spread of information; in fact they are usually driven by information. Most of us lack direct or entirely reliable information about many matters of importance--whether global warming is a serious problem, whether there is a risk of war in India, whether a lot of sugar is really bad for you, whether Mars really exists and what it is like. If you lack a great deal of private information, you might well rely on information provided by the statements or actions of others.

It should be obvious that the Internet, with Websites containing information designed for particular groups, greatly increases the likelihood of diverse but inconsistent cascades. "Cybercascades" occur every day. Many of us have been deluged with e-mail involving the need to contact our representatives about some bill or other--only to learn that the bill did not exist and the whole problem was a joke or a fraud. Even more of us have been earnestly warned about the need to take precautions against viruses that do not exist. And many thousands of hours of Internet time have been spent on elaborating paranoid claims about alleged nefarious activities, including murder, on the part of President Clinton.

With respect to information in general, there is even a "tipping point" phenomenon, creating a potential for dramatic shifts in opinion. After being presented with new information, people typically have different thresholds for choosing to believe or do something new or different. As the more likely believers, that is people with low thresholds, come to a certain belief or action, people with somewhat higher thresholds then join them, soon producing a significant group in favor of the view in question. At that point, those with still higher thresholds may join, possibly to a point where a critical mass is reached, making large groups, societies, or even nations "tip" (Granovetter, 1420). The result of this process can be to produce snowball or cascade effects, as large groups of people end up believing something--whether or not that something is true--simply because other people, in the relevant community, seem to believe that it is true.

The good news is that the Internet can operate to debunk false rumors as well as to start them. But at the same time, the opportunity to spread apparently credible information to so many people can induce fear, error and confusion, in a way that threatens many social goals, including democratic ones. This danger takes on a particular form in a balkanized speech market, as local cascades lead people in dramatically different directions. When this happens, correctives, even via the Internet, may not work, simply because people are not listening to one another.

Of dangers and solutions

For citizens of a heterogeneous democracy, a fragmented communications market creates considerable dangers. There are dangers for each of us as individuals; constant exposure to one set of views is likely to lead to errors and confusions, sometimes as a result of cybercascades. And to the extent that the process entrenches existing views, spreads falsehood, promotes extremism, and makes people less able to work cooperatively on shared problems, there are dangers for society as a whole.

To emphasize these dangers, it is unnecessary to claim that people do or will receive all of their information from the Internet. There are many sources of information, and some of them will undoubtedly counteract the risks I have discussed. Nor is it necessary to predict that most people will speak only with those who are like-minded. Of course many people will seek out competing views. But when technology makes it easy for people to wall themselves off from others, there are serious risks, for the people involved and for society generally.

To be sure, we do not yet know whether anything can or should be done about fragmentation and excessive self-insulation. For purposes of obtaining understanding, few things are more important than to separate the question whether there is a problem from the question whether anything should be done about it. Dangers that cannot be alleviated continue to be dangers. They do not go away if or because we cannot, now or ever, think of decent solutions. It is much easier to think clearly when we appreciate that fact.

ABOUT THE AUTHOR | Cass Sunstein

Cass Sunstein is the Karl N. Llewellyn Distinguished Service Professor of Jurisprudence at the University of Chicago Law School and Department of Political Science. A past member of the President's Advisory Committee on the Public Interest Obligations of Digital Television Broadcasters, he writes regularly for popular magazines and newspapers, including the New York Times Book Review, the New Republic and the American Prospect. He has also appeared on ABC Nightline, the NewsHour with Jim Lehrer, NBC Evening News, ABC World News Tonight, NPR Fresh Air and many other programs.

Sunstein has written extensively on constitutional law, the First Amendment and jurisprudence. He has testified before Congress on many occasions about free speech and other constitutional questions. He has advised many nations about law reform and constitution-making, including Poland, South Africa, Bosnia, China, Russia, Israel and Ukraine. A former law clerk for Justice Thurgood Marshall, he has worked for the Office of Legal Counsel in the United States Department of Justice and has won several awards and commendations from the American Bar Association.

He is the author of Democracy and the Problem of Free Speech (1993), which won the Goldsmith Prize from Harvard for the best book on free speech in that year. His many other books include The Partial Constitution (1993), After the Rights Revolution (1990), Free Markets and Social Justice (1997) and One Case at a Time: Judicial Minimalism on the Supreme Court (1999).

COPYRIGHT | Excerpted from pages 65-69, 73-79, 80-84 and 87-88 of, by Cass Sunstein. Published by Princeton University Press and copyright 2001 Princeton University Press. All rights reserved.

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