How Do Rituals Affect Cooperation?

Hum Nat (2013) 24:115–125 DOI 10.1007/s12110-013-9167-y How Do Rituals Affect Cooperation? An Experimental Field Study Comparing Nine Ritual Types Ronald Fischer & Rohan Callander & Paul Reddish & Joseph Bulbulia Published online: 11 May 2013 # Springer Science+Business Media New York 2013 Abstract Collective rituals have long puzzled anthropologists, yet little is known about how rituals affect participants. Our study investigated the effects of nine naturally occurring rituals on prosociality. We operationalized prosociality as (1) attitudes about fellow ritual participants and (2) decisions in a public goods game. The nine rituals varied in levels of synchrony and levels of sacred attribution. We found that rituals with synchronous body movements were more likely to enhance prosocial attitudes. We also found that rituals judged to be sacred were associated with the largest contributions in the public goods game. Path analysis favored a model in which sacred values mediate the effects of synchronous movements on prosocial behaviors. Our analysis offers the first quantitative evidence for the long-standing anthropological conjecture that rituals orchestrate body motions and sacred values to support prosociality. Our analysis, moreover, adds precision to this old conjecture with evidence of a specific mechanism: ritual synchrony increases perceptions of oneness with others, which increases sacred values to intensify prosocial behaviors. Keywords Cooperation . Entitativity . Evolution . Religion . Ritual . Sacred values Collective rituals are deliberate social behaviors whose means-end purposes cannot be readily inferred from the action sequences of participant behaviors (Konvalinka et al. 2011). Rituals appear to be useless, or worse (Atran 2002). The universal prominence of collective rituals, their costs, and the lack of straightforward instrumental benefits render this peculiar domain of social interaction among the most fascinating and poorly understood areas of human psychology and culture. R. Fischer : R. Callander School of Psychology, Victoria University of Wellington, Wellington, New Zealand P. Reddish LEVYNA: Laboratory for Experimental Research of Religion, Masaryk University, Brno, Czech Republic J. Bulbulia (*) Faculty of Humanities and Social Sciences, Victoria University of Wellington, Wellington, New Zealand 6410 e-mail: [email protected] 116 Hum Nat (2013) 24:115–125 A tradition in social anthropology conjectures that rituals harbor tacit social functions, affecting cooperative outcomes by coordinating the motivations, values, and judgments of ritual participants (Durkheim 1995; Ehrenreich 2006; Levitin 2008; McNeill 1995; Radcliffe-Brown 1922). Anthropologists have identified synchronized actions and sacred values as core elements in the mechanisms by which rituals express cooperative motivations and actions. Following recent convention, we identify such cooperative orientations and behaviors using the term prosociality, noting that much remains to be discovered about this complex domain of human thought and interaction. Why should collective rituals affect prosociality? A century ago, Emile Durkheim conjectured that: “the [ritual] group has an intellectual and moral conformity . . . everything is common to all. Movements are stereotyped; everybody performs the same ones in the same circumstances, and this conformity of conduct only translates the conformity of thought. Every mind being drawn into the same eddy, the individual type nearly confounds itself with that of the race” (1995:18). Durkheim suggested that synchronized activities both draw upon and enhance “intellectual” and “moral” conformity. By moving together as a unit, participants think and value themselves as a unit, which enriches their subsequent cooperation. Recent laboratory experiments offer some preliminary evidence for this actionsynchrony conjecture. Studies investigating synchronous behaviors among pairs (dyadic synchrony and mimicry) show that partners who match each other’s postures, motions, and vocalizations tend to express higher levels of subjective liking, tend to sense enhanced oneness with others (entitativity), and tend to become more charitable (Campbell 1958; Hove and Risen 2009; Miles et al. 2009; Valdesolo and DeSteno 2011; van Baaren et al. 2003, 2004). Notably, prosocial effects from synchrony have been found to extend beyond synchronous pairs to synchronous groups. For example, Wiltermuth and Heath (2009) varied synchronous activities among groups of three and found increased cooperation in groups that moved or vocalized together compared with asynchronous and passive groups. Evidence for cooperative effects from naturally occurring rituals, however, remains scarce (lamented in Haidt et al. 2008; for indirect evidence, see Sosis and Ruffle 2004). Intriguingly, Durkheim speculated that rituals affect cooperation not merely from behavioral synchrony but also by reinforcing conceptions of the “sacred,” which he defined as “things set apart and forbidden” (Durkheim 1995:47). Durkheim’s theory of ritually supported cooperation, then, points beyond shared body movements to shared sacred values. Following Durkheim, contemporary researchers operationalize “sacred values” as “those values that a moral community treats as possessing transcendental significance that precludes comparisons, trade-offs, or indeed any mingling with secular values” (Tetlock 2003:320). In line with Durkheim’s predictions, psychologists have observed that sacred values are strongly linked to prosocial judgements and decision-making (Ginges et al. 2009; Tetlock 2003), and that sincere respect for sacred values reduces moral outrage (Atran et al. 2007). Moreover sacred values embedded in moral convictions have been shown to be strong predictors of social behaviors: knowing about another’s sacred values facilitates accurate predictions for how another will behave (Skitka 2010). Collectively, the research on sacred values offers initial support for a model in which rituals that intensify sacred values will amplify prosocial judgments and behaviors. Quantitative evidence linking ritual cooperation to sacred values, however, is currently lacking. Hum Nat (2013) 24:115–125 117 To better understand how rituals affect cooperation, we investigated nine naturally occurring rituals that varied in synchronous movements and sacred values. Based on Durkheim’s ideas we specifically evaluated two hypothesis: Hypothesis 1: Synchronous movements will be associated with higher levels of prosociality. Hypothesis 2: Sacred values will mediate a ritual’s prosocial effects. To measure the effects of rituals on social attitudes (stated prosociality) we applied standard psychometric scales both before and after ritual activities. To measure the effects of rituals on cooperative behaviors (revealed prosociality) we administered a public goods game after ritual activities. Method Participants A total of 113 participants from nine different community groups participated in our study. The nine groups were all based in Wellington, New Zealand, the country’s capital. New Zealand is an affluent island democracy 2,250 km east of Australia, and home to four million citizens of mainly European decent. The mean age of our sample was 31.12 years (SD=11.23); 49.6% were male; 73.4% identified themselves as New Zealand European. We sampled groups that, based on prior familiarity, would vary in our dimensions of interest. Thus we sought a range of (ostensibly purposeless) activities that varied in levels of body synchrony and sacred attributions. Our preliminary survey revealed that naturally occurring rituals exhibit greater complexity than what is captured by the synchrony versus not-synchrony dichotomy. We therefore sought a subtler coding scheme. Specifically, we categorized activities based on three types of behavior matching. Exact synchrony applied to activities whose participants deliberately matched each other’s movements and/or vocalizations in time for more than 30 min (Yoga, Buddhist chanting, Kirtan [Hindu devotional singing]). Complementary synchrony applied to activities whose participants performed movements and/or vocalizations that were not exactly matched in time but were nevertheless complementary to a shared ritual goal, for more than 30 min (Capoeira [Brazilian martial arts]; Brazilian drumming group; choir; Christian church service). No synchrony applied to activities whose participants did not perform movements/vocalisations that were matched in time or that were complementary to a shared ritual goal (cross-country running group; social poker). This coding scheme was developed during the authors’ meetings, based on preliminary field observations of the ritual groups. Procedure We contacted community groups and sought permission for the study from the group or session leader. Our initial list of approximately fifteen groups presented a range of activities varying along the sacred and synchrony dimensions. We obtained consent 118 Hum Nat (2013) 24:115–125 to conduct the study from nine of these groups. We did not explore the reasons for the non-participation of the remaining groups who declined. We used a pre-post design to examine the effects of rituals on stated prosociality. Participants completed all psychological measures prior to the activity; then they participated in the activity as usual. Immediately following their activity, participants played an economic game and then completed the post-activity questionnaire. After the experiment, participants received their payments, which varied depending on how the public goods game was played. Finally, participants were debriefed. During each ritual activity, the second author took notes at five-minute intervals on levels of synchrony, using standard protocols for field observation (non-participant observations; Fetterman 1998). The other three authors then coded each activity from these notes as either exact or complementary synchrony, or no synchrony. We discussed this coding as a group. Because coding was based on clear behavioral properties (whether partners performed behaviors in exact synchrony, partial synchrony, or without synchrony) and because there was no disagreement in coding among the authors, we did not seek independent ratings for our coding scheme. Measures Economics Game We used a standard public goods game to measure cooperation between ritual participants (Wiltermuth and Heath 2009). The game was played only once. Participants played in groups of 3–5 individuals. Identities were obscured, and all play was strictly anonymous. Participants were told that they had been given $5.00, which they were free to distribute in 50-cent increments to a “public investment,” if/as they desired. Participants were told that all money put into the public investment would be doubled and then distributed equally among all participants in their group. Participants were told that there was no requirement to contribute: the money was theirs, to use as they preferred. Entitativity We used six items to test perceived merging of self with others, an effect that researchers call entitativity (see Denson et al. 2006; Lakens 2010; Lickel et al. 2000). Questions included: “To what extent do you/other people consider this group a coherent group?” and “If people know that you are part of this group they can get a feeling of who you are as a person.” Items were rated on a five-point scale (1=Not at all, 5=Very much). Cronbach’s alpha was 0.74 (Time 1) and 0.77 (Time 2). Trust We used three items from an established trust measure (Pearce et al. 1994; Jarvenpaa et al. 1998): “I can rely on people in this group,” “We have confidence in one another in this group;,” and “Overall, the people in my group are very trustworthy.” We also used the Inclusion of Other in the Self scale (IOS; Aron et al. 1992). The z-transformed items formed a single factor (eigenvalue=2.93 and 3.11, α=0.82 and 0.84 at times 1 and 2, respectively). Sacred Values Three items were used to measure sacred values (Tanner et al. 2009): “This activity is something that you cannot value in terms of money,” “This activity is something that we should not sacrifice no matter how high the benefits,” and “This activity concerns things or values that are untouchable and should never be violated.” Hum Nat (2013) 24:115–125 119 Items were rated on a five-point Likert scale ranging from “completely disagree” to “completely agree” (α=0.79 and 0.84 at times 1 and 2, respectively). At the time of data collection, the scale we used was the only psychometrically validated scale available to measure sacred values. The scale shows good validity and reliability, and it captures core aspects of the experimental and sociological literature on sacred values (Tanner et al. 2009). Control Variables We included demographic questions (age, gender, ethnicity), a question about the length of time each participant had been participating in the group activity (varying from“less than a month” to “5 or more years”), and a question about the frequency of participation (varying from“once a month” to “daily”). Demographic variables were not meaningfully related to the main variables of interest (details available upon request). Frequency of practice, however, was significantly correlated with our dependent variables. We controlled for demographic variables in all analyses (details available on request). Results To test the effect of synchrony on revealed prosociality, we regressed the amount donated to the common pool (Fig. 1) as the dependent variable on length of time and frequency of participation (step 1) and synchrony (step 2). After controlling for participation length and frequency, synchrony significantly explained an additional 4.9% of variance in revealed prosociality (F1,103 =5.69; p<0.05; β=0.23). This result shows that exactly behaviorally synchronous activities were associated with higher levels of prosocial behavior. To test the effect of synchrony on psychological process variables, we used 3×2 mixed effects ANOVA with synchrony (exact synchrony, complementary synchrony, and no synchrony) as a between-subject variable and time (pre- or post-activity) as a within-subject variable. Fig. 1 Average contributions of nine ritual groups in a public goods game 120 Hum Nat (2013) 24:115–125 Entitativity A main effect for synchrony emerged: F1, 102 =11.04, p<0.001, partial η2 =0.18, with entitativity higher in synchrony groups (M=3.69, SD =0.68) and complementary synchrony groups (M=3.67, SD=0.45) than in no-synchrony groups (M=3.14, SD=0.59). The main effect of time and the time×synchrony interaction effect were not significant (F<1.5). This finding supports the hypothesis that synchrony increases perceptions of merging of self with others (Hypothesis 1). Trust A significant effect of synchrony on trust emerged: F1, 102 =3.30, p<0.05, partial η2 =0.061, with the lowest trust found among non-synchronous groups (M=−0.12), intermediate trust among complementary synchrony groups (M=0.49), and highest levels of trust among groups with full synchrony (M=1.07). No other significant main or interaction effect emerged (p>0.30). This finding supports the hypothesis that synchronous activities are associated with higher levels of explicit trust (Hypothesis 1). Direct Sacred Values We found a significant main effect of synchrony on sacred values: F2,97 =17.54, p<0.001, partial η2 =0.27. No other effect was significant. Greater synchrony was associated with greater sacred values (M=3.16, 4.20, and 4.47 for no synchrony, complementary synchrony, and exact synchrony, respectively). This result suggests that greater synchrony is positively associated with an activity’s perceived sacred values (clarifying a mechanism for Hypothesis 2, see below: “Process Model”). Process Model To test the process mechanism by which synchrony increases prosociality, we estimated a path model in MPlus (Muthén and Muthén 1998–2010). Our initial model used synchrony (as coded in discussion among the authors) as the exogenous variable predicting trust, entitativity, and sacred values (all at time 2, controlling for time 1), which in turn predict cooperative behaviors. [Note: controlling for length and frequency of participation did not change any of our findings, it only reduced the degrees of freedom.] The initial model provided a poor fit: χ2 10 =54.95, p<0.001; CFI=0.55, RMSEA=0.21, SRMR=0.11. A revised model (Fig. 2) provided a good fit: χ2 9 =13.69, p=0.13; CFI=0.95, RMSEA= 0.07, SRMR=0.06. On this revised model, synchrony predicted trust, entitativity, and sacred values. Entitativity also predicted sacred values, but only sacred values predicted cooperative behavior in the economic game, thus supporting Hypothesis 2. The path model that best fits the data, then, is one in which feelings of belonging to a distinct and coherent group (entitativity) intensify sacred values, which in turn increases cooperative behaviors in a public goods game. Overall, the model suggests a powerful boost to revealed prosociality from synchronous activities that are associated with sacred values. Discussion Limitations Of the innumerable rituals known to humanity, we have considered only nine. Our selection, moreover, is from a peaceful, affluent, egalitarian, twenty-first-century Hum Nat (2013) 24:115–125 121 Fig. 2 Path analysis shows that synchrony influences prosocial sentiments (entitativity), which influences sacred values to support donations in a public goods game. Frequency of practice is, curiously, negatively associated with such donations democracy. The extent to which our findings generalize remains uncertain. Future field studies should consider the cooperative effects of rituals in different cultural and political settings. Studies among foragers may be important for evaluating evolutionary hypotheses. Yet because forager societies vary, and evolve, we must not load all our hopes for ultimate explanations on that horizon. We operationalized prosociality as reported social attitudes (stated prosociality) and as other directed behavior in an economic game (revealed prosociality). Although such measures are the gold standard for current cooperation research, we expect future researchers will improve on these measures. It remains uncertain, for example, how far monetary behaviors predict non-monetary forms of cooperation. We operationalized sacred values as moral absolutes. We note that sacred values include religious targets, but they may also include distinctly non-religious targets such as rationalism, humanism, justice, democracy, truth, scientific method, beauty, and others. As the reviewer who made this point commented, “I wonder if Fischer et al. would get the same effect in a sample of scientific humanists—readers of Human Nature, say—half of whom chanted the closing lines of The Origin of Species in unison and the other half sang in unison.” Though made somewhat in jest, we think the reviewer makes an important point: researchers should not equate sacred values with religious values. Secular groups with strong goal orientations offer an important target for future ritual research. Findings and Significance Our study brings quantitative support to a long-standing but untested hypothesis that collective rituals combining synchronous body movements and sacred values evoke especially powerful prosociality attitudes and behaviors. Our analysis furthermore clarifies this hypothesis with preliminary evidence for a mechanism. We found that behavioral synchrony modulates sacred values through feelings of oneness (or “entitativity”), which, in turn, enhances cooperative exchange in an economics game. Intriguingly, the model that best fits the data also shows a significant inverse relationship between frequency of ritual practice and cooperation in the economic 122 Hum Nat (2013) 24:115–125 game. A hypothesis predicting this effect comes from Harvey Whitehouse’s Modes Theory, according to which rarely performed rituals elaborate especially powerful personal commitments (Whitehouse 2004). Although none of the rituals we investigated can be counted as rarely performed (all were performed at least one per month), our findings nevertheless suggest that frequency may somewhat impair ritual’s power for supporting cooperative behaviors—revealed prosociality. Clarifying the negative relationship between frequency and prosocial behaviors offers yet another interesting horizon for future research. Why should synchrony and sacred values affect cooperation? We speculate that synchronous behaviors might operate on implicit perception/action systems, such that partners, in seeing and acting as a unity, perceive themselves to be a unity, which elevates a sense of sacredness and expresses higher levels of cooperation. Something approaching this idea seems to be at the basis of Durkheim’s conjecture that a ritual’s “conformity of conduct only translates the conformity of thought. Every mind being drawn into the same eddy, the individual type nearly confounds itself with that of the race” (1995:18). A distinct, and narrower, variant of the perception/action hypothesis holds that by acting as a single unit that is promoting a shared goal, partners receive immediate sensory feedback affording information specifically relevant to cooperative prediction. This narrower version of the goal-specific perception-action hypothesis would help to explain the added boost that partners receive from enhancements to sacred values. Acting for sacred values, collectively, provides a record of cooperative action and thus offers evidence of cooperative responses downstream. Though such processes, if they exist, are likely worked out tacitly, the explicit reasoning behind such effects might run something like this: “If we have acted for each other in a ritual, why not in a market?” (Notably, Reddish et al. 2013 have laboratory evidence indicating strong interactions from synchronous behaviors and collective goal orientations.) An intriguing evolutionary hypothesis about the effects of musical rituals on cooperative outcomes comes from Hagen and Bryant (2003), who argue that group synchrony boosts participants’ confidence in the group’s ability and willingness to respond to a threat in a coordinated fashion, which in turn motivates individuals to assign a high value-weighting to the ritual activity and to maintaining the integrity of a group. We find this conjecture plausible, even if judgments about the efficiency of a collective response to threat do not receive further clarification from our analysis. How might ritual enhancements to cooperation survive against free-rider threats? A commitment-signalling model suggests that partners who perceive each other’s investments in acting for sacred values use these costly displays as signals that index cooperative motivations. Such indexical signals reliably predict cooperative futures (Irons 2001; Sosis 2003). Following Schelling, however, we note that many evolutionary problems of cooperation are probably better modelled as coordination problems with risk (stag hunts) rather than as free-rider dilemmas (Alvard and Nolin 2002; Schelling 2006). We have argued elsewhere that sacred rituals manifest design features that are suited for addressing coordination problems with risk, whose solutions do not rely on interpersonal signalling and detection (Bulbulia 2012). Of course, the commitmentsignalling model remains compatible with the risky coordination model. It would be remarkable, indeed, if there were only one road leading to the Rome of human cooperation. We must, in any event, set aside further speculation about how to answer ultimate “Why synchrony?” and “Why sacred values?” questions. Our data reveal Hum Nat (2013) 24:115–125 123 cooperative effects, but they do not afford clear answers for why such effects should evolve and be conserved. Put another way, our analysis is consistent with, but does not conclusively vindicate, the evolutionary hypothesis that rituals evolve to support cooperation. Future studies are needed to evaluate hypotheses for the evolutionary dynamics that have endowed us with the manifold ritual practices that pervade human social life. The importance of our study consists in this: we show that synchronous rituals are associated with higher levels of cooperation, offering support for Hypothesis 1. Secondly, we find that sacred rituals are associated with increased levels of cooperation, offering support for Hypothesis 2. Thirdly, we extend the synchrony/sacred conjecture with evidence for a proximate mechanism by which (a) synchronous actions (b) enhance feelings of oneness (entitativity) to (c) intensify sacred values, thus (d) increasing prosocial behaviors. Wider Significance Although anthropologists and psychologists share a common interest—humans—the disciplines of anthropology and psychology are often opposed. Our study, one of many in the rapidly expanding field of experimental anthropology, suggests their mutual relevance. By bringing psychological methods to the field, we were able to offer quantitative support for a long-standing, but untested, anthropological conjecture that naturally occurring collective rituals recruit behavioral synchrony and sacred values to increase prosociality. By quantifying key variables and effects, moreover, we found a specific mechanism for ritual cooperation: behavioral synchrony modulates prosocial sentiments, which increase sacred values to enhance prosocial exchange. Generally, then, our study shows how quantitative methods can be employed to test anthropological conjectures, helping to resolve what might otherwise prove to be interminable debates. Our study also reveals the importance of field research for psychological science. Despite a surge of psychological interest in the effects of behavioral synchrony on social cognition, psychologists have yet to consider how body synchrony interacts with strongly held social values. Our analysis suggests that sacred values may be the vital missing link in the mechanisms by which naturally occurring rituals affect cooperative exchange. More generally, this finding illustrates how psychologists may improve their models by taking to the field and examining variables that cannot be readily manipulated in laboratory environments. It is fitting that evidence for Durkheim’s ritual theory comes in the centenary of his Elementary Forms of The Religious Life. It is widely known that in this work, Durkheim proposed a model for ritual cooperation. Less familiar, however, is the scientific reserve with which Durkheim presented his model. We see this reserve, mixed with optimism, in Durkheim’s unpretentious plea for new collaborative science: [T]here is a whole science that must be formed, a complex science that can advance but slowly and by collective labour, and to which the present work brings some fragmentary contributions in the nature of an attempt (Durkheim 1995:32–33). Although anthropological and psychological methodologies might appear to be strange bedfellows, we believe that experimental anthropology will increasingly clarify 124 Hum Nat (2013) 24:115–125 questions that have been the subject of long-standing anthropological debates, whose answers have also eluded laboratory psychologists. Durkheim’s century awaits us. Acknowledgments We are grateful to Diana Boer for her helpful comments. We are grateful to the editor of Human Nature, Jane Lancaster, and to four anonymous referees for their helpful comments and encouragement. 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Psychological Science, 15(1), 71–74. van Baaren, R. B., Holland, R. W., & Steenaert, B. (2003). Mimicry for money: behavioral consequences of imitation. Journal of Experimental Social Psychology, 39(4), 393–398. doi:10.1016/S00221031(03)00014-3. Whitehouse, H. (2004). Modes of religiosity: A cognitive theory of religious transmission. Lanham: AltaMira Press. Wiltermuth, S. S., & Heath, C. (2009). Synchrony and cooperation. Psychological Science, 20(1), 1–5. Ronald Fischer is a Reader in Psychology in the Centre for Applied Cross-Cultural Research at Victoria University of Wellington. He has published over 100 articles and book chapters on cultural differences in psychological processes, cultural values and research methods, working in Brazil, East Africa and South East Asia. Rohan Callander has recently completed his Master’s degree in psychology at Victoria University, New Zealand. His thesis is titled, “The Effects of Collective Group Rituals on Prosociality.” Paul Reddish received his PhD in psychology from Victoria University, New Zealand. His thesis was “Why Sing and Dance? An Examination of the Cooperative Effects of Group Synchrony.” Reddish is currently a postdoctoral fellow at the Laboratory for Experimental Research of Religion (LEVYNA) at Masaryk University in the Czech Republic, the world's first experimental laboratory in the study of religion (http://www.levyna.cz). Joseph Bulbulia teaches in the Religious Studies Programme at Victoria University of Wellington, New Zealand, and publishes widely in evolutionary religious studies. He is president-elect of the International Association for the Cognitive Science of Religion; a fellow of the Religion Cognition and Culture Unit at Aarhus University, Denmark; and a principal investigator at LEVYNA, Masaryk University, Czech Republic. View publication stats