Solidarity, synchronization and collective action

For people to act collectively in actual situations—in contrast to public goods experiments—goal ambiguity, diversity of interests, and uncertain costs and benefits stand in their way. Under such conditions, people seem to have few reasons to cooperate, yet the Arab revolutions, as conspicuous examples, show that collective action can take place despite the odds. I use the Kuramoto model to analyze how people in a cohesive network topology can synchronize their salient traits (emotions, interests or other), and show that synchronization happens in a phase transition, when group solidarity passes a critical threshold. This model can yield more precise predictions of outbursts of collective action under adverse conditions, and casts a new light on different measures of social cohesion. A remarkable feature of humans is that they can act collectively, even though individuals are tempted to defect and reap the benefits of others’ efforts [19]. This achievement is even more remarkable if one realizes that in contrast to public goods experiments of collective action, where the collective good—money—is clearly defined at the outset, public goods in actual situations, from revolutions to reorganizations, are often ambiguous. Yet more challenging, participants differ in their interests in, and shares of, those public goods. Under conditions of ambiguity, uncertainty and diversity, most people seem to have few reasons to cooperate. Nevertheless we can witness that in numerous cases, people somehow manage to get to action in the face of all odds. ∗Department of Sociology and Anthropology, University of Amsterdam, Oudezijds Achterburgwal 185, 1012 DK Amsterdam, the Netherlands. Email: j.p.bruggeman@uva.nl. 1 ar X iv :1 31 2. 68 09 v3 [ ph ys ic s. so cph ] 2 8 Ja n 20 14 In this note I ask the question if under adverse conditions, when neither cost-benefit ratios nor reputations can win people over to contribute to collective goods, dilemma’s of cooperation can be solved through “interaction rituals” wherein individuals’ traits (emotions, interests or other) are synchronized. To this end I use Yoshiki Kuramoto’s model of synchronization [25], to be discussed first. Because synchronization is highly sensitive to network topology, I compare two concepts of social cohesion, k -core and k -connectivity, for their synchronization potential. Results are somewhat ambiguous and require laboratory experiments on human subjects. Solidarity and synchronization According to one of the founders of sociology, Emile Durkheim, groups of people are bond together by social cohesion [9]. With modern network theory in mind, one could say that cohesion consists in part of social ties that people have with others, and for another part of solidarity that people have with their group as a whole. Importantly, people are not identical, and i ∈ {1, 2, . . . , N} group members each have their own character ωi, shaped prior to current interactions on a given network. Their solidarity λ can be enhanced through intensified interaction, such as collective singing or noise making (see documentaries on protests such as Tahrir square), religious practices [10], initiation boot camps in organizations [13], military training or other interaction rituals with a shared focus [6]. In some of these interaction rituals, people perform synchronized body movements [12], as to induce their emotional synchronization. Future research should detail out the relation between interaction rituals and solidarity; here I assume a monotonic relationship, exogenous to the model. Although for the model (Eq.1) it makes no difference whether an interaction ritual increases solidarity, the strength of network ties, or both, I assume for simplicity that only solidarity varies; all ties between individuals are symmetric, Wij = Wji = 1 (and absent ties Wij = 0), such that connected i and j mutually influence each other; and, the network does not change over the period of observation. For the moment I also assume that everybody has the same solidarity value (coupling strength), which will be loosened to individualized λi in the next section. An individual’s current trait—emotion, A generalization of the Kuramoto model [2] allows for the network and its synchronization to co-evolve, such that the ties and their strengths Wij(t) change according to homophily and homeostasis. For homophily, see the main text below; homeostasis means individuals’ limited capacity to maintain ties, such that stronger ties with some people imply weaker or no ties with others, empirically found by [16] and others.

[1]  William H. McNeill,et al.  Keeping Together in Time: Dance and Drill in Human History. , 1995 .

[2]  Jurgen Kurths,et al.  Synchronization in complex networks , 2008, 0805.2976.

[3]  Bart J. Wilson,et al.  Incremental Commitment and Reciprocity in a Real-Time Public Goods Game , 2001 .

[4]  Vito Latora,et al.  Emergence of structural patterns out of synchronization in networks with competitive interactions , 2011, Scientific reports.

[5]  David G. Rand,et al.  Humans Display a 'Cooperative Phenotype' that is Domain General and Temporally Stable , 2014 .

[6]  P. Ball Critical Mass: How One Thing Leads to Another , 2004 .

[7]  V. Calhoun,et al.  Information flow between interacting human brains: Identification, validation, and relationship to social expertise , 2015, Proceedings of the National Academy of Sciences.

[8]  M. A. Muñoz,et al.  Entangled networks, synchronization, and optimal network topology. , 2005, Physical review letters.

[9]  J. Mannion The Ties That Bind Us , 1993 .

[10]  Ananish Chaudhuri Sustaining cooperation in laboratory public goods experiments: a selective survey of the literature , 2011 .

[11]  Michael D. Buhrmester,et al.  Brothers in arms: Libyan revolutionaries bond like family , 2014, Proceedings of the National Academy of Sciences.

[12]  J. Deneubourg,et al.  From Social Network (Centralized vs. Decentralized) to Collective Decision-Making (Unshared vs. Shared Consensus) , 2012, PloS one.

[13]  Quentin D. Atkinson,et al.  The cultural morphospace of ritual form ☆: Examining modes of religiosity cross-culturally , 2011 .

[14]  David G. Rand,et al.  Spontaneous giving and calculated greed , 2012, Nature.

[15]  Manfred Milinski,et al.  Multiple gossip statements and their effect on reputation and trustworthiness , 2008, Proceedings of the Royal Society B: Biological Sciences.

[16]  R. Collins,et al.  Interaction Ritual Chains , 2004 .

[17]  Sergey N. Dorogovtsev,et al.  k-core (bootstrap) percolation on complex networks: Critical phenomena and nonlocal effects , 2006, Physical review. E, Statistical, nonlinear, and soft matter physics.

[18]  How Do Rituals Affect Cooperation? , 2013, Human nature.

[19]  D. R. White,et al.  Structural cohesion and embeddedness: A hierarchical concept of social groups , 2003 .

[20]  N. Christakis,et al.  Social Networks and Cooperation in Hunter-Gatherers , 2011, Nature.

[21]  A. Jadbabaie,et al.  On the stability of the Kuramoto model of coupled nonlinear oscillators , 2005, Proceedings of the 2004 American Control Conference.

[22]  R. Collins Violence: A Micro-sociological Theory , 2008 .

[23]  Ljupco Kocarev,et al.  Consensus and Synchronization in Complex Networks , 2013 .

[24]  Jeroen Bruggeman Social Networks: An Introduction , 2008 .

[25]  Alex Arenas,et al.  Synchronization reveals topological scales in complex networks. , 2006, Physical review letters.

[26]  P. Richerson,et al.  Not by Genes Alone , 2004 .

[27]  T. Schelling Micromotives and Macrobehavior , 1978 .

[28]  M. Tomasello,et al.  Understanding and sharing intentions: The origins of cultural cognition , 2005, Behavioral and Brain Sciences.

[29]  Yoshiki Kuramoto,et al.  Self-entrainment of a population of coupled non-linear oscillators , 1975 .

[30]  Joseph A. Bulbulia,et al.  Synchronized arousal between performers and related spectators in a fire-walking ritual , 2011, Proceedings of the National Academy of Sciences.

[31]  E. Durkheim,et al.  De la Division du Travail Social. , 1894 .

[32]  S. Strogatz From Kuramoto to Crawford: exploring the onset of synchronization in populations of coupled oscillators , 2000 .

[33]  E. Durkheim,et al.  Les formes élémentaires de la vie religieuse , 1991 .

[34]  Yamir Moreno,et al.  Reputation drives cooperative behaviour and network formation in human groups , 2015, Scientific Reports.

[35]  Sergey N. Dorogovtsev,et al.  Lectures on Complex Networks , 2010 .

[36]  T. Milbrandt,et al.  9. Émile Durkheim , 2011 .

[37]  Caroline Kelly,et al.  Group Identification, Intergroup Perceptions and Collective Action , 1993 .

[38]  Barry Wellman,et al.  Social Network Analysis: An Introduction 1 , 2010 .

[39]  Guido Caldarelli,et al.  Low-Temperature Behaviour of Social and Economic Networks , 2013, Entropy.

[40]  A. Heifetz Rational Ritual: Culture, Coordination, and Common Knowledge. , 2004 .

[41]  Adilson E Motter,et al.  Heterogeneity in oscillator networks: are smaller worlds easier to synchronize? , 2003, Physical review letters.

[42]  Scott Atran,et al.  Religious and Sacred Imperatives in Human Conflict , 2012, Science.

[43]  Edoardo Gallo,et al.  The effects of reputational and social knowledge on cooperation , 2015, Proceedings of the National Academy of Sciences.

[44]  O. J. Harvey,et al.  Intergroup Conflict And Cooperation: The Robbers Cave Experiment , 2013 .

[45]  David G. Rand,et al.  Human cooperation , 2013, Trends in Cognitive Sciences.

[46]  Samuel Bowles,et al.  Supporting Online Material Materials and Methods Som Text Figs. S1 and S2 Table S1 References and Notes the Coevolution of Parochial Altruism and War , 2022 .

[47]  Ronald T. Wohlstein,et al.  Collective Locomotion as Collective Behavior , 1986 .

[48]  A. Mikhailov,et al.  Entrainment of randomly coupled oscillator networks by a pacemaker. , 2004, Physical review letters.

[49]  Florian Dörfler,et al.  Synchronization in complex networks of phase oscillators: A survey , 2014, Autom..

[50]  S. Tarrow,et al.  Power in Movement: Social Movements, Collective Action and Politics , 1997 .

[51]  F. Harary,et al.  The cohesiveness of blocks in social networks: Node connectivity and conditional density , 2001 .

[52]  P. McGraw,et al.  Analysis of nonlinear synchronization dynamics of oscillator networks by Laplacian spectral methods. , 2006, Physical review. E, Statistical, nonlinear, and soft matter physics.

[53]  J. Diamond The wealth of nations , 2004 .

[54]  E. Durkheim De la division du travail social , 1894 .

[55]  Joseph Bulbulia,et al.  Let’s Dance Together: Synchrony, Shared Intentionality and Cooperation , 2013, PloS one.

[56]  S. Tarrow,et al.  Power in Movement: Social Movements, Collective Action and Politics , 1994 .

[57]  J. Glasby All together now... , 2003, Nature Reviews Microbiology.

[58]  Jürgen Jost,et al.  Synchronization of networks with prescribed degree distributions , 2006, IEEE Transactions on Circuits and Systems I: Regular Papers.

[59]  Stephen B. Seidman,et al.  Network structure and minimum degree , 1983 .

[60]  Xin Hu,et al.  Exact solution for first-order synchronization transition in a generalized Kuramoto model , 2014, Scientific Reports.

[61]  Frans B. M. de Waal,et al.  The Antiquity of Empathy , 2012 .

[62]  Alex Pentland,et al.  Time-Critical Social Mobilization , 2010, Science.

[63]  Esteban Moro Egido,et al.  Time as a limited resource: Communication Strategy in Mobile Phone Networks , 2013, Soc. Networks.

[64]  H. Simon,et al.  A mechanism for social selection and successful altruism. , 1990, Science.

[65]  Daniel A. Levinthal,et al.  Exploration and Exploitation in Organizational Learning , 2007 .

[66]  M. McPherson,et al.  Birds of a Feather: Homophily in Social Networks , 2001 .

[67]  Bert Klandermans,et al.  How Group Identification Helps to Overcome the Dilemma of Collective Action , 2002 .

[68]  Scott S. Wiltermuth,et al.  Synchrony and Cooperation , 2009, Psychological science.

[69]  Jolanda Jetten,et al.  When group membership gets personal: a theory of identity fusion. , 2012, Psychological review.

[70]  H. Moore,et al.  ENGINEERING CULTURE. , 2022, Science.

[71]  Sergio Gómez,et al.  Explosive synchronization transitions in scale-free networks. , 2011, Physical review letters.

[72]  Karline Soetaert,et al.  Solving Differential Equations in R , 2012 .

[73]  Yamir Moreno,et al.  Synchronization of Kuramoto oscillators in scale-free networks , 2004 .

[74]  P. Richerson,et al.  The evolution of indirect reciprocity , 1989 .

[75]  Santo Fortunato,et al.  Community detection in graphs , 2009, ArXiv.

[76]  H. Bekkering,et al.  Joint action: bodies and minds moving together , 2006, Trends in Cognitive Sciences.