SOCIAL PSYCHOLOGY AND INTERGROUP CONFLICT
Writer and satirist Jonathan Swift was at his most cynical when he described humanity as “the most pernicious race of odious vermin that nature ever suffered to crawl upon the surface of the earth.” Yet, viewed in terms of the sheer number of conflicts dotted over the map of the world or the barbarity of some of the acts carried out by one human being against another (whether in Bosnia, Northern Ireland, Rwanda, or a host of other countries), it is easy to understand Swift’s jaundiced view. These conflicts may be based on race, on religious differences (e.g., Northern Ireland, most of former Yugoslavia), on language (e.g., Belgium), or on various combinations of these. The diversity of phenomena subsumed under the term intergroup conflict is also potentially vast, including prejudice, discrimination, injustice, perpetuation of inequality, oppression, ethnic cleansing, and genocide. This chapter focuses primarily on prejudice and discrimination (i.e., negative attitudes and behaviors with respect to an out group as compared to an in group) and is divided into two main parts, each of which is a relatively brief and selective review of a large literature. The first part lays out some of the main social psychological bases of intergroup conflict, and the second part presents some of the most promising social psychological interventions to reduce intergroup conflict.
We gratefully acknowledge grants from the Central Community Relations Unit (Northern Ireland) and the Templeton Foundation during the time at which this chapter was written, and we thank Katy Greenland and Mark Rubin for their comments on an earlier version of this chapter.
SOCIAL PSYCHOLOGICAL BASES OF INTERGROUP CONFLICT AND GROUP PERSPECTIVES
“The problem of Northern Ireland is a heady brew of history, geography, religion and nationality, of rival rights and allegiances, of competition for power and territory, of deep bitterness.” This analysis of “The Troubles” in Northern Ireland by journalist David McKittrick (1998) could surely be given as accurately for almost any intergroup conflict. That is why conflict attracts and requires the research attention of, among others, anthropologists, historians, sociologists, economists, and political scientists, as well as social psychologists. But there are also distinct social psychological bases of intergroup conflict, which primarily concern what is special about our behavior as members of social groups. Although some social psychologists have attempted to account for intergroup conflict in terms of some intra individual factor (e.g., personality or frustration leading to aggression; see Billig, 1976), a far more convincing account can he provided by concentrating on the distinct nature of intergroup phenomena.
The roots of these perspectives can he traced back to Sumner’s (1906; see also Brewer, 1979) sociological writings on the basic state of conflict between the “we group” (or in group) and “other groups” (or out groups). In general, Sumner (1906) called intergroup biases ethnocentrism, defined as the “view of things in which one’s own group is the center of everything, and all others are scaled or rated with reference to it” (p. 13). This general tendency can be seen in preferences for in group characteristics, products, customs, languages, speech styles, and so on. Sumner saw such biases as resulting from intergroup competition and functioning to preserve in group solidarity and justify the exploitation of out groups. However, whereas Sumner saw ethnocentrism as universal, social psychological research has examined what conditions lead to an increase or decrease in ethnocentrism.
Realistic Group Conflict Theory
This approach to intergroup relations (Brewer, 1979; LeVine & Campbell, 1972; Sherif, 1966) assumes that group conflicts are rational in the sense that groups have incompatible goals and compete for scarce resources. Thus the source of conflict is “realistic.” Sherif and colleagues carried out a number of famous field studies of boys at summer camps, who were split up into different groups and engaged in various competitive behaviors (e.g., Sherif, 1966; Sherif, Harvey, White, Hood, & Sherif, 1961). They concluded that competition causes intergroup conflict and that there needed to be some positive and functional interdependence between groups before conflict between them would abate (i.e., they must be made to cooperate). Sherif and his colleagues created these conditions in the form of superordinate goals: goals that neither group could attain on its own and which superseded other goals each group might have had. Sherif also reported that a single superordinate goal was not sufficient to reduce intergroup conflict; a series of cumulative superordinate goals was required.
Notwithstanding the pioneering influence of Sherif’s work and, indeed, the extensive, cross cultural psychological evidence that competition promotes aggression (Bonta, 1997), Sherif’s studies did not show that conflict of interest was a necessary requirement for the emergence of intergroup hostility. As Billig (1976) noted, anecdotal evidence from the early study by Sherif et al. (1961) actually indicates that the negative reactions to an out group emerged at a stage prior to the planned introduction of competition. Thus mere knowledge of the other group’s presence was sufficient to trigger the first instances of intergroup discrimination. This realization of the potency of social categorization led to Tajfel’s later work on social identity.
Social Identity Theory
According to social identity theory (Abrams & Hogg, 1990; Tajfel, 1978; Tajfel & Turner, 1979), individuals define themselves to a large extent in terms of their social group memberships and tend to seek a positive social identity. This social identity consists of those aspects of an individual’s selfimage that derive from the social categories to which the individual perceives himself or herself to belong and to the value and emotional significance ascribed to that membership. Thus it is a self definition in terms of group membership. A positive social identity is achieved by comparing one’s own group with other groups to establish a positively valued psychological distinctiveness for the in group vis a vis the out group.
Emphasizing that motivational as well as cognitive factors underlie intergroup differentiation, social identity theory holds that positive comparisons (intergroup differences that favor the in group) provide a satisfactory social identity, whereas negative comparisons (differences that favor the out group) convey an unsatisfactory identity. Social identity differs from earlier group perspectives in two key respects. First, in contrast to Sumner’s claim that ethnocentrism is rampant, social identity theory predicts that members of social groups will differentiate primarily on dimensions that provide them with a favorable view of their own group (i.e., dimensions on which the in group is superior to the out group). Moreover, intergroup discrimination is often driven by “in group favoritism” rather than “outgroup derogation” (Brewer, 1979). Second, in contrast to Sherif’s claim that competitive goals cause conflict, social identity theory argues that social categorization per se can cause intergroup discrimination.
Tajfel and colleagues demonstrated the power of social categorization in their “minimal groups paradigm” (Tajfel, Billig, Bundy, & Flament, 1971). In the paradigm, participants are classified as members of two discrete groups ostensibly on the basis of trivial criteria (e.g., preference for one of two abstract painters, over or underestimation of dots, and even allocation to group X or Y according to the toss of a coin). In fact, allocation to a group is always random. Participants then have to distribute rewards between pairs of other participants (not themselves) using specially designed booklets that assess the strength of various response strategies. The authors of the original research considered the groups to be “minimal” for the following reasons: (a) Categorization into in groups or out groups was based on trivial criteria, (h) there was no explicit conflict of interests, (c) nor had there been previous hostility, (d) participants did not engage in face to¬face social interaction, and (e) there was no rational link between economic sell interest and the strategy of favoring one’s own group.
The most striking finding to emerge from these studies was that participants, although they made some effort to be fair in their allocations, showed a persistent tendency to give higher rewards to another (unknown) in group member than to another (unknown) out group member (Bourhis, Sachdev, & Gagnon, 1994; Brewer, 1979; Turner, 1981). Participants were particularly keen to ensure that their fellow in group member received a higher reward than the out group member, rather than to maximize rewards gained for the in group or to maximize joint gain (i.e., for both groups). According to social identity theory, the only way for participants in these studies to obtain a positive social identity is by identifying with the groups into which they are categorized and then ensuring that their group comes off best in the only available comparison between the groups (i.e., giving more rewards to the in group than to the out group).
Before continuing, we might pause here and ask whether these groups do, in fact, represent “minimal” groups or, as Tajfel (1978, p. 42) himself suggested, whether in the context of an artificial and bare laboratory study they constitute “maximal” groups. They remind one of Jonathan Swift’s satire on political or religious animosity in Gulliver’s Travels the implacable division between those who open an egg at the large end or at the small end (“Big Endians” vs. “Little Endians”). Out of quite small beginnings can sometimes grow large conflicts, and it would be difficult to overestimate the importance of social categorization and its link via social comparison to social identity and the need for psychological distinctiveness. This claim is supported by the many different applications of social identity to intergroup relations outside the laboratory (Tajfel, 1982) and its position as the dominant explanatory framework for the study of intergroup relations in social psychology (Brewer & Brown, 1998).
Outside the laboratory, social identity has had to confront the fact that groups in conflict often differ in status and that changing status relations and their perceived legitimacy are crucial determining characteristics of intergroup relations (Turner & Brown, 1978; Van Knippenberg & Ellemers, 1990). Thus when lower status or minority groups perceive the dominant group’s position as illegitimate and unstable, they may use a variety of strategies to obtain a positive identity. They may search for a positive identity by redefining characteristics of their own group that had previously been seen as negative, or they may find new dimensions for making comparisons between the groups or a new comparison group. Only later may the out group be directly confronted, as when comparisons are made directly on dimensions such as power and status and when the lower status group demands equality. This in turn may threaten the identity of the dominant group, leading to a backlash. All these strategies are discussed in detail by Tajfel (1978) and illustrated in the context of the conflict in Northern Ireland by Cairns (1982).
In particular, social identity theory helps us to understand the behavior of those whose identity is perceived to be threatened and whose behavior might otherwise seem quite irrational or pointless. Consider an example from Northern Ireland the insistence of members of the Orange Order (Protestant Unionists) that they be allowed to march down Garvaghy Road, located in the center of a Catholic area of Drumcree. In the same article quoted earlier, McKittrick (1998) explained that “In recent years, the parades have taken on a character of Protestant consolation, expressing not jubilation in Unionist ascendancy but a sense that at least one parade can be got through.” Thus getting the parade through has become an end in itself. A Jesuit priest quoted in the same article added that “Protestants have been under pressure since 1968, and they have lost power and status to a far greater extent than many Catholics realize. As a result, they’re afraid of their whole identity [emphasis added] being abolished completely.” From the perspective of social identity theory, the insistence of the Protestant community on marching down one particular street (for just 7 minutes) can be understood in terms of their feeling that their identity is threatened and that such opportunities must be taken to stand up to the Catholic community and to show that Protestant identity is still important and valued.
IS THERE SOMETHING SPECIAL ABOUT INTERGROUP BEHAVIOR?
At this point the reader might well be asking himself or herself this question. Tajfel’s (1978) answer was a clear “yes,” which he illustrated by comparing interpersonal and intergroup forms of behavior. He proposed a hypothetical continuum, with end points of “pure” interpersonal and intergroup behavior, respectively. Interpersonal behavior concerns relations that are completely determined by the interpersonal characteristics of those involved (e.g., two friends). Intergroup behavior concerns relations that are defined totally in terms of individuals’ memberships in social groups or categories (e.g., a member of one group killing an innocent, unknown member on the other side of a conflict simply because he or she was a member of the out group).
Tajfel suggested that intergroup behavior could be distinguished by three criteria. First, at least two clearly identifiable social categories should be present in the situation (e.g., a Hutu and a Tutsi, a Catholic and a Protestant, a Serb and a Croat). Second, there should be little variability of behavior or attitude within each group. Intergroup behavior tends to be uniform (i.e., “we” agree about “them”), whereas interpersonal behavior shows a range of individual differences. Third, a member of one group should show little variability in his or her perception or treatment of members of the other group (i.e., “they” are “all alike”). In Tajfel’s (1978) words, outgroup members are treated as “undifferentiated items in a unified social category” (p. 45).
There is evidence that people’s behavior is indeed qualitatively different in group settings (Brown & Turner, 1981). For example, when group membership is salient (e.g., during conflict), the individual tends to become “depersonalized” in the group. This is not a loss of identity (“de individuation”) but a shift from personal to social identity. A concern with the ingroup takes over from a concern with the self, in group favoritism replaces self favoritism, the self is stereotyped as an in group member, and the ingroup is viewed as coherent and homogeneous (Turner, Hogg, Oakes, Reicher, & Wetherell, 1987). There is also now extensive evidence that groups are more competitive and aggressive than individuals (e.g., Schopler & Insko, 1992). In a similar vein, Brewer (1997) has proposed an “ingroup out group schema,” consisting of three principles likely to operate in any social situation in which a particular in group out group categorization is made salient. The intergroup accentuation principle refers to assimilation within category boundaries and contrast between categories; all members of the in group are seen as more similar to the self than members of the outgroup. The in group favoritism principle refers to the selective generalization of positive affect (trust, liking) to fellow in group, but not to out-group, members. The social competition principle refers to the fact that intergroup social comparison is typically perceived in terms of competition, rather than comparison, with the out group.
Of equal importance to the empirical evidence are the theoretical implications that follow from the distinction between interpersonal and intergroup behavior (Brown &. Turner, 1981). First, theories that attempt to explain intergroup phenomena by reference to interpersonal relations are unlikely to be very predictive. Second, if the individual is depersonalized in the group, then what affects the group as a whole has implications for the individual. Intergroup behavior is likely to be influenced by intergroup relations of status, power, and so on, not by interpersonal relations. Third, some variables that have one effect on interpersonal relations may have a different effect on intergroup relations. For example, similarity may have attractive properties at an interpersonal level, but it may threaten group distinctiveness and lead to intergroup discrimination (Brown, 1984). For all these reasons, Tajfel (1979) came to conclude that intergroup behavior requires a different level of analysis from intragroup or interpersonal behavior.
TYPES OF INTERGROUP CONFLICT
Although we argue strongly that social psychology has a contribution to make to the study of conflict, we do not wish to exaggerate its importance. At the end of their seminal paper on social identity theory, Tajfel and Turner (1979) distinguished between a number of types of conflict that helps to highlight where social psychology’s contribution should be greatest.
Objective Versus Subjective Conflict
When we talk about conflict, we normally have in mind what Tajfel and Turner have called “objective” conflicts over power, wealth, or territory. These objective conflicts obviously have their determinants outside the realm of psychology and require an analysis in terms of social, economic, political, and historical structures. Objective conflicts can be distinguished from psychological, symbolic or “subjective” conflicts, such as attempts to establish positively valued distinctiveness. Although distinct, objective and subjective conflicts are often interwoven, and subjective conflict can exist long after objective disparities disappear (according to Deutsch, 1973, the notion of destructive conflicts that are likely to continue after initiating causes have become irrelevant). Political scientist John Whyte (1990) has written about the conflict in Northern Ireland: “It seems to go beyond what is required by a rational defence of the divergent interests which undoubtedly exist [between Catholics and Protestants}” (p. 94). And for the very reason that the problems involved are more symbolic or psychological, they may be more difficult to deal with (Cairns & Darby, 1988).
Explicit Versus Implicit Conflict
A further distinction can be made between explicit and implicit conflicts. Explicit conflict is legitimized and institutionalized by rules or norms (e.g., the competition between groups in Sherifs studies or the World Cup competition for international football teams). Tajlel and Turner (1979) proposed that the behavior toward the out group in this kind of conflict can, in turn, be classified into two categories. Instrumental behavior refers to actions aimed at causing the in-group to win the competition (such behavior can be explained in terms of the motive to win). Noninstrumental behavior is more interesting, psychologically, because it is gratuitous discrimination against out groups and has no sense outside the context of intergroup relations. A prime example is the ascription of negative stereotypes to members of out groups and, indeed, to the group as a whole. Generally a set of traits is attributed to all (or most) members of the category, and individuals belonging to the category are assumed to be similar to each other and different from the in group on this set of traits. Treating the out group in this way makes them more predictable, can be used to justify discriminatory behavior, and can help group members to differentiate the in group positively from the out-group (Linville, 1998; Oakes, Haslam, & Turner, 1994; Tajfel, 1981).
Finally, implicit conflict refers to conflict that exists in the absence of explicit institutionalization (e.g., experimental participants’ preference for relative gain at the expense of the out group in the minimal groups paradigm, even when this means a decrease in objective reward and where there is no explicit conflict of interests). Tajfel and Turner (1979) referred to the many cases in “real life” where “differentiations of all kinds are made between groups by their members although, on the face of it, there are no reasons for these differentiations to occur” (p. 47). A tragic example is provided by the Hutu and Tutsi in Rwanda (Keane, 1995; Prunier, 1995).
Contrary to widespread beliefs, the Hutu and Tutsi are not ethnic or tribal groups. They have the same language, religion, and culture, and there has been a history of extensive intermarriage and even people exchanging identities. In fact, they are essentially the same people, but differences between them were emphasized by colonialists, leading to exaggeration of quite small differences in physical attributes such as height and skin color. As Prunier has reported in this volume (chapter 8), this social differentiation concluded with a deliberate genocide, the causes of which were complex but included a psychological component. As Prunier put it, “Genocide has a lot to do with how people perceive each other” (see also Staub, 1989; Staub, chapter 18, this volume).
Thus social psychological aspects of conflict are most evident in the case of implicit conflict and are also illustrated by noninstrumental behaviors associated with explicit conflicts. But they can also be important where objective and subjective conflicts have become inseparable and where a contemporary subjective conflict has outlived a more ancient objective one. This overview of social psychological bases of intergroup conflict illustrates that there are many ways in which social psychology can illuminate the study of conflict, and many points at which a conflict can become psychological. We believe the social identity approach has the most to offer this area theoretically and that many apparently pointless conflicts become more understandable when viewed as, at least in part, attempts to establish, maintain, or defend cherished social identities. Finally, we have also argued that intergroup behavior is distinct from interpersonal behavior and that specific types of conflict can be identified in which social psychological considerations are crucial.
SOCIAL PSYCHOLOGICAL INTERVENTIONS TO REDUCE INTERGROUP CONFLICT
In this second part of the chapter, we give an overview of two main types of intervention aimed at reducing intergroup conflict (Hewstone, 1996). The first is based on bringing about more positive and cooperative contact between members of previously hostile groups, and the second attempts to change the structure of social categorizations. Both interventions may be aimed at changing various aspects of intergroup perception and behavior, but we will focus on three main types of change identified by Brewer and Miller (1988). The first is a change in attitudes toward the social structure as a whole, making the view of an out group less negative or preferably more positive. The second is an increase in the perceived variability of the out group, whereby the perceiver comes to view the outgroup in a less simple, more differentiated way. The third kind of change involves a decrease in category use (“de categorization”), whereby the perceiver comes to see the old categorization as less, or no longer, useful for identifying and classifying individuals.
Contact Between Members of Different Groups
There is now extensive evidence that contact between members of different groups, under appropriate conditions, can improve intergroup relations (Allport, 1954/1979; also see Pettigrew, 1998, for a recent review). Favorable conditions include cooperative contact between equal-status members of the two groups, in a situation that allows individuals to get to know each other on more than a superficial basis, and with the support of relevant social groups and authorities (Cook, 1978). But there remain serious limitations to the so called contact hypothesis (Hewstone & Brown, 1986).
One of the most serious limitations is that participants in cooperative contact programs, even if they do come to view one or a small number of individuals from the other group more positively, do not necessarily generalize their positive attitudes and perceptions. They may not generalize beyond the specific situation in which the positive contact took place, and they may not generalize from specific contact partners to the group as a whole (Hewstone & Brown, 1986). Recent work on intergroup contact is aimed at overcoming precisely this limitation.
Another serious practical limitation is that optimal contact is hard to bring about on a large scale, especially for adult participants (for young people it is somewhat easier when incorporated into formal education). Wright, Aron, McLaughlin Volpe, and Ropp (1997) have proposed an “extended contact effect” to overcome this limitation, in which knowledge that a fellow in group member has a close relationship with an out group member is used as a catalyst to promote more positive intergroup attitudes. This extended contact is second hand, rather than involving the participants in direct intergroup contact themselves, and so it could potentially bring about widespread reductions in prejudice without everyone having to have out group friendships themselves. This second hand contact may also overcome the problem that contact with an out group is associated with “intergroup anxiety” (Stephan & Stephan, 1985). This anxiety may be caused by low or poor quality contact, negative expectations or stereotypes about the out group, or a history of intergroup conflict. Importantly, intergroup anxiety is associated with poor recall of the contact experience, increased avoidance, and increased out group stereotyping (Wilder, 1993).
If there are theoretical and practical limitations to intergroup contact, why the insistence on its implementation? The answer to this question has two parts, the first dealing with why contact has to be engineered if it is to take place at all, and the second justifying why we should bother to bring about contact. Why do we have to engineer contact? Unless proactive attempts are made to bring about contact, many people avoid intergroup contact, an effect likely to be exacerbated in the context of conflict where any dealing with the “other side” may be proscribed and violations severely sanctioned (e.g., in Northern Ireland people in mixed, Catholic Protestant relationships have been frequently targeted and, in several cases, brutally murdered). In addition, society itself may be so segregated that unless we intervene there is almost no opportunity for contact.
This is the case in Northern Ireland, where there is extensive educational (Gallagher, 1995) and residential segregation (Poole & Doherty, 1996). The implications are illustrated by a problem we encountered in a recent survey on contact and prejudice in Northern Ireland, using a representative sample of the population. As part of the pilot work testing some of our questions, we received feedback from the survey organization that “interviewers found that in some of the 100 percent Protestant/Catholic areas where they were interviewing, the people had absolutely no contact with people of a different religion.”
Why bother to bring about contact at all? Contact between groups can sometimes be the cause of hostility, especially when it leads to intergroup comparisons concerning inequalities of land, wealth, and so on. But in principle we believe that some contact, especially where it can be made positive and cooperative, is desirable. The absence of contact is likely to reduce the likelihood of future contact, strengthen the assumption that the two groups have different (even irreconcilable) beliefs, maintain intergroup anxiety, and reinforce the boundary between groups (Hewstone, 1996). It is worth noting that even one positive encounter with a member of the other group, although it is unlikely to change the stereotype of an out, group in general, can sometimes bring about change in perceived group variability, revealing that “they” are not “all alike” (Hamburger, 1994). Bishop Desmond Tutu told the story of his astonishment when an unknown White priest (Father Trevor Huddleston) raised his hat to Tutu’s mother, a simple cook. “For the first time,” Tutu said, he “realized that all whites were not the same” (cited in The Guardian, 1998).
Interpersonal Versus Intergroup Contact
As we have noted, a major limitation of research on contact is the failure to generalize from positive interpersonal encounters to views of the out group as a whole. People seem to find it very easy to “explain away” (Pettigrew, 1979) the behavior of one or a few people who disconfirm their stereotype and assign these exceptions to a “subtype” that is not typical of the group as a whole (Hewstone, 1994), unless the out group member is perceived as typical and a dispositional attribution can be made for the counterstereotypic behavior (Wilder, Simon, & Faith, 1996). Hewstone and Brown (1986) therefore argued that unless contact can be characterized as intergroup (i.e., between individuals as group representatives), it is unlikely to generalize to the group as a whole.
As specialists in this area, we are often asked “How do you explain what happened in Yugoslavia?” This European state was home to various ethnic groups who lived together (12% of all marriages in Yugoslavia and 40% in Sarajevo were mixed; Botev & Wagner, 1993), and yet it was catapulted into civil war and genocide. It became clear that close friendships with members of different ethnic groups offered no special immunity against outrageous acts committed in pursuit of the policy of ethnic cleansing. The closest friend of Dusko Tadic, member of the Serb minority in the Bosnian town of Kozarac, was Muslim policeman Emir Karabasic (his friend even served as a pall bearer at Tadic’s father’s funeral). Tadic was later accused on 34 counts at the international war crimes tribunal at The Hague, one of which was beating to death four of his former neighbors, including Emir, in the Omarska detention camp. Although this case is particularly tragic, it may be quite representative in the sense that 50% of respondents to one survey in the region reported betrayal by neighbors belonging to the dominant or majority group (Botev & Wagner, 1993).
In another more positive example Ahmed, a Bosnian, related how his life was saved when Serbian forces intercepted a group of Muslims trying to escape from Srebrenica to the haven of Tuzla:
My father was just ahead of me. In front of the tank, he turned to the left with the other men. Without thinking, I continued walking straight ahead with the women and children. After a few yards a hand reached out and grabbed my right shoulder. It was a Serb soldier, a neighbor of mine from Srebrenica. He shoved a blanket in my arms and motioned for me to put it on my head. He literally saved my life (cited in Stover & Peress, 1998).
Yet even in this latter case the close interethnic friendship was not enough to prevent the Serb joining up to a force intent on cleansing the area of Muslims.
It is obviously asking an enormous amount of any kind of contact that it should “inoculate” the recipient against the host of forces urging it in the direction of ethnic conflict (e.g., group pressures such as conformity, calls to national identity, and threats to one’s family). We believe, however, that intergroup contact is more likely to provide a bulwark against these forces than is interpersonal contact. Thus we have argued that group affiliations should still be clear in contact situations and that when members of one group meet members of the other group, they should both be seen as, at least to some extent, typical of their groups (Hewstone & Brown, 1986). Only under these circumstances should cooperative contact lead to more positive ratings of the out group as a whole, for which there is now extensive evidence (e.g., Brown, Vivian, & Hewstone, 1999; Van Oudenhoven, Groenewoud, & Hewstone, 1996; Wilder, 1984). Despite this evidence, there are some potential dangers associated with intergroup contact. Where intergroup conflict is extreme, contact may promote anxiety (Islam & Hewstone, 1993), and it may be better to begin with positive interpersonal contact, and later make group memberships salient.
Changing Social Categorizations
The interventions reviewed in this section start from the premise that since social categorization is the cause of discrimination, an improvement in intergroup relations must be brought about by reducing the salience of existing social categories (Brewer & Miller, 1984), These interventions try to achieve this, however, by very different means. The first, decategorization, seeks to eliminate categorization; the second and third, re categorization and crossed categorization, seek to alter which categorizations are used (Wilder, 1986).
Brewer and Miller’s (1984, 1988) “personalization” model suggests that contact between members of different groups should be differentiated (allowing for distinctions to be made among out group members) and personalized (allowing for perceptions of the uniqueness of out group members). The goal then is a more interpersonally oriented and “non category¬based” form of responding that allows members to “attend to information that replaces category identity as the most useful basis for classifying each other” (Brewer & Miller, 1984, p. 288). For example, an employer who had previously been selecting only members of his or her own ethnic group might learn that this information is not very useful in predicting whether someone will be a good employee and that a much better basis for such a decision would be to look beyond the category to the individual applicants’ educational qualifications.
Brewer and Miller and their colleagues have investigated their model in a series of experimental studies (Bettencourt, Brewer, Rogers Croak, & Miller, 1992; Miller, Brewer, & Edwards, 1985). The studies confirmed the hypothesized effects of personalized contact. Participants who adopted an interpersonal focus displayed significantly less in group favoritism than did either those who focused on the task or those in a control condition. Participants also differentiated among out-group members more in the interpersonal conditions, and there was a strong correlation between perceived similarity of out-group members (to each other) and the degree of intergroup bias shown.
Personalization aims to, and can, achieve de categorization: Individuation of out group members results in the category being seen as less “useful” and, thus, being used less often. This intervention may also succeed in changing perceived group variability, encouraging a more complex and differentiated perception of the out-group (Hamburger, 1994), which may ultimately reduce the likelihood of applying a stereotype to individual members in the future (Brewer & Brown, 1998; Ryan, Judd, & Park, 1996). However, the very conditions that promote personalization impede generalization of attitudes from individual members of the out group to the outgroup as a whole (Scarberry, Ratcliff, Lord, Lanicek, & Desforges, 1997). The beneficial effects of personalized contact may also be restricted to majority groups, with members of minority groups showing more bias under these conditions than when focusing on the task (Bettencourt, Charlton, & Kernahan, 1997).
Both re categorization and crossed categorization are interventions inspired theoretically by social identity theory (Tajfel, 1978) and, more recently, by self categorization theory (e.g., Turner et al., 1987). These theories emphasize that we all typically belong to several social categories and therefore may have a series of social identifications, one of which is salient at any given time. Self categorization theory develops the earlier social identity perspective by arguing that self can be conceived on a number of levels of inclusiveness (e.g., me as an individual, me as a group member, or me as a human being). The level at which the self is defined determines how one relates to others, including members of the same group.
Gaertner, Dovidio, Anastasio, Bachman, and Rust (1993) argued that intergroup bias can be reduced by factors that transform members’ perceptions of group boundaries from “us” and “them” to a more inclusive “we.” They acknowledged that several factors influence intergroup bias and conflict, but their “common in group identity” model regards the cognitive representations of the situation as the critical mediating variable (Dovidio, Gaertner, Isen, & Lowrance, 1995; Dovidio, Gaertner, Isen, Rust, & Guerra, 1988; Dovidio, Gaertner, & Validzic, 1998; Gaertner et al., 1999). Although a representation of the situation as one involving two groups is thought to maintain or enhance intergroup biases, decategorized (i.e., separate individuals) or re categorized (i.e., common in group identity) representations are expected to reduce tension, albeit in different ways. De categorization reduces bias through a process that moves initial in group members away from the self and toward out group members; thus former in group members are seen less positively and as more evaluatively similar to out group members. Re categorization, in contrast, should reduce bias by increasing the attractiveness of former out group members, once they are included within the superordinate group structure. The common in group identity model resolves in group versus out group conflict by changing group boundaries and creating a superordinate identity.
There is extensive support for the common in group identity model from sophisticated laboratory experiments. Bias was lower with a one group than a two group representation, and attraction to former out group members was increased (Gaertner, Mann, Murrell, & Dovidio, 1989). Intergroup cooperation reduced bias via its effect on cognitive representations of social categorization (Gaertner, Mann, Dovidio, Murrell, & Pomare, 1990). It is also quite easy to find real life illustrations consistent with the common ingroup identity model, such as the national cohesion of nine different ethnic groups (half Muslim, half Christian) in Eritrea, fighting a “people’s war” against Ethiopia. But common in group identity may only be short lived, or it may not be realistic in the face of powerful ethnic and racial categorizations (e.g., the break up of former Yugoslavia into Serbs, Croats, Bosnians, etc.). A more successful strategy may involve a superordinate identity and distinctive subgroup identities. This would overcome a limitation of both the de categorization and re categorization perspectives which they seek to de-emphasize cherished identities. Yet, because membership of ethnic and other kinds of groups often provides a source of desired social identity (Tajfel, 1978), it would be impractical as well as undesirable for all parties concerned to ignore distinctive memberships.
As Brewer (1997) concluded, “De categorization and re categorization as appealing as these concepts are are inherently limited in their applicability when we move from the laboratory to real life situations in which social groups are very large and the context is highly politicized” (p. 203). One solution to this problem, as was noted in passing, is to use a combination of different strategies. It has been suggested, for example (Hewstone, 1996), that where intergroup relations are characterized by high anxiety, initial contact should be interpersonal, only later making group memberships salient and addressing intergroup differences. Pettigrew (1998) suggested that at the initial stage, contact should involve interpersonal (decategorized) relations to promote early positive interactions. In the slightly longer term, group differences should be highlighted to promote categorization and therefore generalization. Finally, re categorization becomes possible over the course of extended contact.
Most realistic intergroup contexts involve several categorizations, some of which coincide and some of which cut across each other. Thus “others” may be out group on one dimension (e.g., Black-people vs. White-people in the United States) but in group on another (e.g., Southerners vs. Northerners; Reed, 1982). Where others can be classified as out group members on multiple dimensions, Brewer and Campbell (1976) labeled the situation as one involving “converging boundaries,” where discrimination is likely to be increased. Many instances of intergroup conflict in the real world involve just such multiple converging social categorizations. For example, in Belfast, Northern Ireland, Catholics and Protestants tend to live in different places (e.g., Shankhill Road vs. Ardoyne), espouse different politics (NationalistRepublican vs. Unionist Loyalist), and even support different football teams (e.g., Cliftonville vs. Linfield).
The idea that crossed categorization might be used as an intervention comes from early anthropological work showing lower levels of conflict in societies with cross cutting structures than in those with pyramidal segmentary structures (see Crisp & Hewstone, 1999, for a review). Social psychologists later analyzed how crossed categorization should affect the categorization process itself (Vescio, Hewstone, Crisp, & Rubin, 1999). According to Doise’s (1978) “category differentiation model,” single or simple categorization leads to two cognitive processes: an accentuation of both the differences between categories (an “interclass effect”) and similarities within categories (an “intraclass effect”). In contrast, the crossing of two categorizations leads to “convergence” between the categories (weakening the interclass effect) and “divergence” within each category (weakening the intraclass effect). Thus, for example, if we imagine a case in which one dimension (A/B) is crossed with another (X/Y), the accentuation of perceived similarities within one category (e.g., A) will be counteracted by a simultaneous accentuation of perceived differences, because category A contains two different subgroups according to another (e.g., X/Y —> AX and AY) categorization (Vanbeselaere, 1991). As a result of these processes, intergroup discrimination based on the A/B categorization should, theoretically, be reduced or even eliminated.
The results of experimental work did not, however, typically show that crossed categorization could eliminate discrimination or even reduce it below the level of discrimination aimed at single out groups. Most studies do, however, show greatest bias against the double out group, which is reduced when the target is a member of the in group on one dimension and the out group on the other (Migdal, Hewstone, & Mullen, 1998). This result suggests that crossed categorization can still be effective as an intervention, by helping to reduce bias against existing double (or multiple) out-groups. It should do this, in part, by making perceivers aware that the outgroup consists of different subgroups (thus it may achieve differentiation). It should also reduce the importance of any one category, force the perceiver to classify other individuals in terms of multiple dimensions, and point to at least some similarities between groups (Vanbeselaere, 1991).
Like the other interventions reviewed, there remain limitations to the use of crossed categorization. Because one categorization is normally dominant in cases of conflict, even crossing multiple alternative categories may not weaken discrimination (Brewer, Ho, Lee, & Miller, 1987; Hewstone, Islam, & Judd, 1993). Crossing categories may also not help when categories are correlated (Eurich Fulcher & Schofield, 1995), as is the case in many real conflicts (e.g., in Nigeria, the Ibo are predominantly Christian and the Hausa predominantly Muslim). There is also a need for further basic research exploring when and how various models of crossed categorization might operate (Crisp & Hewstone, 2000; Miller, Urban, & Vanman, 1998) and what type of change is brought about by this intervention. Nonetheless, crossed categorization does provide an important intervention for reducing bias against out groups characterized by converging boundaries.
CHANGING SOCIAL STRUCTURES
Our emphasis in this part of the chapter, and our bailiwick as social psychologists, is on social psychological interventions. Nonetheless, we acknowledge that “conflict resolution must go beyond changes in perceptions, attitudes, and qualities to the creation of enduring structures that institutionalize equality, autonomy, and respect among different groups” (Fisher, 1994, p. 61). These structures include federalization and consociational arrangements for what McGarry and O’Leary (1993) called “the macro political regulation of ethnic conflict” (see also O’Leary, chapter 3, this volume). For example, electoral systems can be designed to fragment the support of a majority ethnic group, induce a majority ethnic group to behave moderately toward another ethnic group, or encourage multi ethnic coalitions. We wish to emphasize, however, that whatever political structures are advocated, this decision should be guided by what we know about social categorization and its impact on conflict. At present some scholars advocate structural arrangements that cross cut ethnic boundaries, whereas others argue that they should follow ethnic boundaries (Horowitz, 1985).
We also acknowledge that resolution of social conflict involves more than changing negative stereotypes and improving intergroup attitudes. The admirable work of Bishop Tutu’s “Truth and Reconciliation Commission” in South Africa reminds us that the residue of conflict goes much deeper than prejudice and discrimination. Bishop Tutu concluded his foreword to the 3,500 pages of his final report by proposing, “Having looked the past in the eye, having asked for forgiveness, and having made amends, let us shut the door on the past not in order to forget it but in order not to allow it to imprison us” (cited in The Daily Telegraph, 1998). Only very recently, encouraged by a research initiative of the Templeton Foundation, have scholars in this area considered the importance of the concept of forgiveness in intergroup conflict. Yet, in principle, interventions that succeed in reducing prejudice and discrimination could still leave participants unable to forgive, and certainly to forget, earlier atrocities. We therefore propose that social psychologists should take a wider view of outcome measures that should be addressed by their conflict interventions and a correspondingly broader perspective on the types of intervention that they should be evaluating. An interesting recent example is a study of collective guilt with respect to one’s own treatment of another group and how this may affect emotions experienced and behavioral reactions (Doosje, Branscombe, Spears, & Manstead, 1998).
This overview of social psychological interventions to reduce intergroup conflict shows that different interventions can achieve different kinds of change. We have argued that an absence of contact between groups will polarize images and reinforce group boundaries; moreover, intergroup contact under appropriate conditions can bring about generalized change in outgroup attitudes. Changing the structure of social categorizations is also important, and de categorization, re-categorization, and crossed categorization can reduce or change the salience of existing categorization in a complementary fashion. Indeed, the interventions most likely to succeed will integrate these perspectives. Changing the social structure may also, ultimately, be necessary, but it should be guided by what we know about the functioning of social categorization.
We hope to have shown in this chapter some of the main contributions of a social psychological approach to conflict and how this approach is different from the contributions made by specialists from other disciplines. We have demonstrated the potency of social categorization and argued that the social identity approach helps us to understand why social categorization can so easily lead to intergroup conflict. Although there is certainly more to most social conflicts than mere psychology, we have argued that most intergroup conflicts have an identifiable social psychological component. This psychological component can exist alongside and exacerbate objective conflict, and attacking this component of conflict is important in and of itself. We have also reviewed what we see as the most important group based social psychological interventions aimed at reducing intergroup conflict. These include intergroup contact under appropriate conditions and attempts to reduce the salience of existing social categorizations. These interventions are not intended as a panacea for conflict, but rather as a set of ideas that can be used to achieve specific types of improved intergroup relations. These interventions, like our social psychological perspective, are not meant to replace alternative interventions, but to be used as part of a necessary multidisciplinary approach to intergroup conflict.
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 The interested reader can consult the “conflict data service” of the Initiative on Conflict Resolution And Ethnicity (INCORE) at www.incore.ulst.ac.uk/cds/.
 Social identity theory argues that social categorization arouses self evaluative social comparison processes whereby individuals strive to obtain a positive self esteem, but the evidence for this “self-esteem hypothesis” is unconvincing (Rubin & Hewstone, 1998).
 Although there are many such marches, which punctuate the summer in Northern Ireland on an annual basis, the Drumcree march is a particular trouble spot and is also particularly salient, because it took place in 1998 just a few days after the conference on which this volume is based.