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Toward a computational theory of social groups: A finite set of cognitive primitives for representing any and all social groups in the context of conflict

Published online by Cambridge University Press:  27 April 2021

David Pietraszewski Open the ORCID record for David Pietraszewski [Opens in a new window]
David Pietraszewski*
Affiliation:
Center for Adaptive Rationality, Max Planck Institute for Human Development, Lentzeallee 94, 14195 Berlin, Germany [email protected]://www.mpib-berlin.mpg.de/en/staff/david-pietraszewski
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Abstract

We don't yet have adequate theories of what the human mind is representing when it represents a social group. Worse still, many people think we do. This mistaken belief is a consequence of the state of play: Until now, researchers have relied on their own intuitions to link up the concept social group on the one hand and the results of particular studies or models on the other. While necessary, this reliance on intuition has been purchased at a considerable cost. When looked at soberly, existing theories of social groups are either (i) literal, but not remotely adequate (such as models built atop economic games), or (ii) simply metaphorical (typically a subsumption or containment metaphor). Intuition is filling in the gaps of an explicit theory. This paper presents a computational theory of what, literally, a group representation is in the context of conflict: It is the assignment of agents to specific roles within a small number of triadic interaction types. This “mental definition” of a group paves the way for a computational theory of social groups – in that it provides a theory of what exactly the information-processing problem of representing and reasoning about a group is. For psychologists, this paper offers a different way to conceptualize and study groups, and suggests that a non-tautological definition of a social group is possible. For cognitive scientists, this paper provides a computational benchmark against which natural and artificial intelligences can be held.

Keywords

Commonsense reasoningcomputational theoryinformation-processingintergroup relationssocial cognitionsocial groupstriadic interactionviolence/aggression
Type
Target Article
Information
Behavioral and Brain Sciences , Volume 45 , 2022 , e97
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Copyright © The Author(s), 2021. Published by Cambridge University Press

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References

Abrams, D., & Rutland, A. (2008). The development of subjective group dynamics. In Levy, S. R, & Killen, M. (Eds.), Intergroup attitudes and relations in childhood through adulthood (pp. 47–65). Oxford University Press.Google Scholar
Alexander, R. A. (1987). The biology of moral systems. Routledge.Google Scholar
Allport, G. W. (1924). Social psychology. Houghton Mifflin.Google Scholar
Allport, G. W. (1954/1958). The nature of prejudice. Doubleday Anchor.Google Scholar
Archer, J. (1988). The behavioural biology of aggression. Cambridge University Press.Google Scholar
Axelrod, R. (1984). The evolution of cooperation. Basic Books.Google Scholar
Balliet, D., Wu, J., & De Dreu, C. K. W. (2014). Ingroup favoritism in cooperation: A meta-analysis. Psychological Bulletin, 140, 1556–1581.Google Scholar
Balliet, D., Tybur, J. M., & Van Lange, P. A. M. (2017). Functional interdependence theory: An evolutionary account of social situations. Personality and Social Psychology Review, 21(4):361–388, https://doi.org/10.1177/1088868316657965.Google Scholar
Barrett, H. C. (2015). The shape of thought: How mental adaptations evolve. Oxford University Press.Google Scholar
Bar-Tal, D. (Ed.). (2001). Intergroup conflicts and their resolution: A social psychological perspective. Taylor & Francis.Google Scholar
Bissonnette, A., Perry, S., Barrett, L., Mitani, J. C., Flinn, M., Gavrilets, S., & de Wall, F. B. M. (2015). Coalitions in theory and reality: A review of pertinent variables and processes. Behaviour, 152, 1–56.Google Scholar
Block, N. (1997). Semantics, conceptual role. Routledge Encyclopedia of Philosophy. Retrieved from http://cogprints.org/232/1/199712005.html.Google Scholar
Böhm, R., Rusch, H., & Baron, J. (2018). The psychology of intergroup conflict: A review of theories and measures. Journal of Economic Behavior & Organization. https://doi.org/10.1016/j.jebo.2018.01.020.Google Scholar
Böhm, R., Rusch, H., & Gürerk, Ö. (2016). What makes people go to war? Defensive intentions motivate retaliatory and preemptive intergroup aggression. Evolution and Human Behavior, 37, 29–34.Google Scholar
Böhm, R., Rusch, H., & Baron, J. (2020). The psychology of intergroup conflict: A review of theories and measures. Journal of Economic Behavior & Organization, 178, 947–962.Google Scholar
Bornstein, G. (2003). Intergroup conflict: Individual, group, and collective interests. Personality and Social Psychology Review, 7, 129–145.Google Scholar
Brewer, M. B. (2001). Identity and conflict. In Bar-Tal, D. (Ed.), Intergroup conflicts and their resolution: A social psychological perspective (pp. 125–143). Taylor & Francis.Google Scholar
Brown, D. E. (1991). Human universals. McGraw-Hill.Google Scholar
Brown, R. (2000). Group processes. Blackwell.Google Scholar
Burani, N., & Zwicker, W. S. (2003). Coalition formation games with separable preferences. Mathematical Social Sciences, 45, 27–52.Google Scholar
Byrne, R. W., & Whiten, A. (Eds.). (1988). Machiavellian intelligence: Social expertise and the evolution of intellect in monkeys, apes, and humans. Clarendon.Google Scholar
Campbell, A. (2015). Women's competition and aggression. In Buss, D. M. (Ed.), The handbook of evolutionary psychology, volume 2: Integrations (pp. 684–703). Wiley.Google Scholar
Campbell, D. T. (1958). Common fate, similarity, and other indices of the status of aggregates of persons as social entities. Behavioural Science, 3, 14–25.Google Scholar
Caplow, T. (1959). Further development of a theory of coalitions in the triad. American Journal of Sociology, 64, 488–493.Google Scholar
Chase, I. D. (1985). The sequential analysis of aggressive acts during hierarchy formation: An application of the “jigsaw puzzle” approach. Animal Behavior, 1985, 86–100.Google Scholar
Chomsky, N. (1980). Rules and representations. The Behavioral and Brain Sciences, 3, 1–61.Google Scholar
Cikara, M., Bruneau, E., Van Bavel, J. J., & Saxe, R. (2014). Their pain gives us pleasure: How intergroup dynamics shape empathic failures and counter-empathic responses. Journal of Experimental Social Psychology, 55, 110–125.Google Scholar
Cikara, M., Van Bavel, J. J., Ingbretsen, Z. A., & Lau, T. (2017). Decoding “us” and “them”: Neural representations of generalized group concepts. Journal of Experimental Psychology: General, 5, 621–631.Google Scholar
Daly, M. (2015). Interpersonal conflict and violence. In Buss, D. M. (Ed.), The handbook of evolutionary psychology, volume 2: Integrations (pp. 669–683). Wiley.Google Scholar
Dawes, R. M., Van De Kragt, A. J. C., & Orbell, J. M. (1988). Not me or thee but we: The importance of group identity in eliciting cooperation in dilemma situations: Experimental manipulations. Acta Psychologica, 68, 83–97.Google Scholar
DeDeo, S., Krakauer, D. C., & Flack, J. C. (2010). Inductive game theory and the dynamics of animal conflict. PLoS Computational Biology, 6(5), e1000782, https://doi.org/10.1371/journal.pcbi.1000782.Google Scholar
De Dreu, C. K. W., & Gross, J. (2019). Revisiting the form and function of conflict: Neurobiological, psychological, and cultural mechanisms for attack and defense within and between groups. Behavioral and Brain Sciences, 42, 1–66.Google Scholar
De Dreu, C. K. W., Gross, J., Méder, Z., Giffin, M., Prochazkova, E., Krikeb, J., & Columbus, S. (2016). In-group defense, out-group aggression, and coordination failures in intergroup conflict. Proceedings of the National Academy of Sciences, 133, 10524–10529.Google Scholar
De Dreu, C. K. W., & Van Vianen, A. E. M. (2001). Managing relationship conflict and the effectiveness of organizational teams. Journal of Organizational Behavior, 22, 309–328.Google Scholar
Dennett, D. (1969/2002). Content and consciousness. Routledge.Google Scholar
Dennett, D. (1988). Cognitive wheels: The frame problem in artificial intelligence. In Pylyshyn, Z. W. (Ed.), The robot's dilemma: The frame problem in artificial intelligence (pp. 41–65). Ablex.Google Scholar
DeScioli, P., & Kurzban, R. (2009). Mysteries of morality. Cognition, 112, 281–299.Google Scholar
DeScioli, P., & Kurzban, R. (2013). A solution to the mysteries of morality. Psychological Bulletin, 139, 477–496.Google Scholar
Deutsch, M. (1962). Cooperation and trust: Some theoretical notes. In Jones, Manasa R. (Ed.), Nebraska symposium on Motivation (pp. 275–320). University of Nebraska Press.Google Scholar
Dunham, Y. (2018). Mere membership. Trends in Cognitive Sciences, 22, 780–793.Google Scholar
Etzioni, O. (2018). Learning common sense: A grand challenge for academic AI research. Talk at the Office of Naval Research.Google Scholar
Fiske, S. T., & Neuberg, S. L. (1990). A continuum of impression formation from category-based to individuating processes: Influences of information and motivation on attention and interpretation. Advances in Experimental Social Psychology, 23, 1–74.Google Scholar
Forsyth, D. R. (2014/2019). Group dynamics (7th ed.). Cengage.Google Scholar
Gamson, W. A. (1961). A theory of coalition formation. American Sociological Review, 26, 373–382.Google Scholar
Gershman, S. J., Pouncy, H. T., & Gweon, H. (2017). Learning the structure of social influence. Cognitive Science, 41, 545–575.Google Scholar
Gershman, S. J., & Cikara, M. (2020). Social-structure learning. Current Directions in Psychological Science, 29(5), 460–466.Google Scholar
Glowacki, L., Wilson, M. L., & Wrangham, R. W. (2020). The evolutionary anthropology of war. Journal of Economic Behavior & Organization, 178, 963–982.Google Scholar
Goldstone, R. L., Roberts, M. E., & Gureckis, T. M. (2008). Emergent processes in group behavior. Current Directions in Psychological Science, 17, 10–15.Google Scholar
Gonzalez, C., Ben-Asher, N., Martin, J. M., & Dutt, V. (2015). A cognitive model of dynamic cooperation with varied interdependency information. Cognitive Science, 39, 457–495.Google Scholar
Grammer, K. (1992). Intervention in conflicts among children: Contexts and consequences. In Harcourt, A. H., & de Waal, F. B. M. (Eds.), Coalitions and alliances in humans and other animals (pp. 259–283). Oxford University Press.Google Scholar
Gross, J., & De Dreu, C. K. W. (2019). The rise and fall of cooperation through reputation and group polarization. Nature Communications, 10, 776 https://doi.org/10.1038/s41467-019-08727.Google Scholar
Hamilton, D. L., Sherman, S. J., & Castelli, L. (2002). A group by any other name – The role of entitativity in group perception. European Review of Social Psychology, 12, 139–166.Google Scholar
Harcourt, A. H. (1988). Alliances in contests and social intelligence. In Byrne, R.W., & Whiten, A. (Eds.), Machiavellian intelligence (pp. 132–152). Clarendon Press.Google Scholar
Harcourt, A. H., & deWall, F. B. M. (Eds.). (1992). Coalitions and alliances in humans and other animals. Oxford University Press.Google Scholar
Hardy, I. C. W., & Briffa, M. (Eds.). (2013). Animal contests. Cambridge University Press.Google Scholar
Haslam, S. A., Reicher, S. D., & Platow, M. J. (2011). The new psychology of leadership: Identity, influence and power. Psychology Press.Google Scholar
Heider, F. (1958). The psychology of interpersonal relations. Erlbaum.Google Scholar
Insko, C. A., & Schopler, J. (1987). Categorization, competition and collectivity. In Hendrick, C. (Ed.), Group processes (Vol. 8, pp. 213–251). Sage.Google Scholar
Ip, G. W., Chiu, C., & Wan, C. (2006). Birds of a feather flock together: Physical versus behavioral cues may lead to trait- versus goal-based group perception. Journal of Personality and Social Psychology, 90, 368–381.Google Scholar
Jackendoff, R. S. (1992). Languages of the mind: Essays on mental representation. MIT Press.Google Scholar
Kamermans, M., & Schmits, T. (2004). The history of the frame problem. Artificial Intelligence, 86, 116.Google Scholar
Koykka, C., & Wild, G. (2017). Concessions, lifetime fitness consequences, and the evolution of coalitionary behavior. Behavioral Ecology, 28, 20–30.Google Scholar
Lau, T., Gershman, S. J., & Cikara, M. (2020). Social structure learning in human anterior insula. eLife, 9, e53162.Google Scholar
Lau, T., Pouncy, H. T., Gershman, S. J., & Cikara, M. (2018). Discovering social groups via latent structure learning. Journal of Experimental Psychology: General, 147, 1881–1891.Google Scholar
Levine, R., & Campbell, D. (1972). Ethnocentrism: Theories of conflict, ethnic attitudes, and group behavior. Wiley.Google Scholar
Lewin, K. (1948). Resolving social conflict. Harper.Google Scholar
Lorenz, K. (1948/1996). The natural science of the human species: An introduction to comparative behavioral research, the “Russian Manuscript” (1944–1948). MIT Press.Google Scholar
Lickel, B., Hamilton, D. L., Wieczorkowska, G., Lewis, A., Sherman, S. J., & Uhles, A. N. (2000). Varieties of groups and the perception of group entitativity. Journal of Personality and Social Psychology, 78, 223–246.Google Scholar
Liska, G. (1962). Nations in alliance: The limits of interdependence. Johns Hopkins University Press.Google Scholar
Lopez, A. C. (2017). The evolutionary psychology of war: Offense and defense in the adapted mind. Evolutionary Psychology, 15, 1–23. https://doi.org/10.1177/1474704917742720.Google Scholar
Lopez, A. C. (2020). Making ‘my’problem ‘our’problem: Warfare as collective action, and the role of leader manipulation. The Leadership Quarterly, 31(2), 101294.Google Scholar
Marr, D. (1982). Vision: A computational investigation into the human representation and processing of visual information. W H Freeman.Google Scholar
Marr, D., & Nishihara, H. K. (1978). Representation and recognition of the spatial organization of three-dimensional shapes. Proceedings of the Royal Society of London B, 200, 269–294.Google Scholar
McGrath, J. E. (1984). Groups: Interaction and performance. Prentice-Hall.Google Scholar
Mesterton-Gibbons, M., Gavrilets, S., Gravner, J., & Akcay, E. (2011). Models of coalition or alliance formation. Journal of Theoretical Biology, 274(1), 187–204.Google Scholar
Minsky, M. (1961). Steps toward artificial intelligence. Proceedings of the IRE, 49, 8–30.Google Scholar
Minsky, M. (1974). A framework for representing knowledge. Artificial Intelligence Memo No. 306.Google Scholar
Moncrieff, M., & Lienard, P. (2019). What war narratives tell about the psychology and coalitional dynamics of ethnic violence. Journal of cognition and culture, 19(1–2), 1–38.Google Scholar
Mueller, E. T. (2015). Commonsense reasoning: An event calculus based approach. Morgan Kaufmann.Google Scholar
Oliver, P. E. (1993). Formal models of collective action. Annual Review of Sociology, 19, 271–300.Google Scholar
Palminteri, S., Wyart, V., & Koechlin, E. (2017). The importance of falsification in computational cognitive modeling. Trends in Cognitive Sciences, 21(6), 425–433.Google Scholar
Park, J. H., & Van Leeuwen, F. (2015). Evolutionary perspectives on social identity. In Zeigler-Hill, V., Welling, L., & Shackelford, T. (Eds.), Evolutionary perspectives on social psychology (pp. 115–125). Springer.Google Scholar
Patton, J. Q. (1996). Thoughtful warriors: Status, warriorship, and alliance in the Ecuadorian Amazon. PhD dissertation, University of California Santa Barbara.Google Scholar
Patton, J. Q. (2000). Reciprocal altruism and warfare: A case from the Ecuadorian Amazon. In Cronk, L., Chagnon, N., & Irons, W. (Eds.), Adaptation and human behavior: An anthropological perspective (pp. 417–436). Aldine de Gruyter.Google Scholar
Peirce, C. S. (1931–1935). Collected papers of Charles Sander Peirce. In Weiss, P., Hartshorne, C., & Burks, A. W. (Eds.). Harvard University Press.Google Scholar
Perc, M., & Szolnoki, A. (2010). Coevolutionary games – A mini review. BioSystems, 99, 109–125.Google Scholar
Perry, S., Barrett, H. C., & Manson, J. H. (2004). White-faced capuchin monkeys show triadic awareness in their choice of allies. Animal Behaviour, 67, 165–170.Google Scholar
Pietraszewski, D. (2012). The elementary dynamics of intergroup conflict and revenge. Behavioral and Brain Sciences, 36, 32–33.Google Scholar
Pietraszewski, D. (2013). What is group psychology? Adaptations for mapping shared intentional stances. In Banaji, M., & Gelman, S. (Eds.), Navigating the social world: What infants, children, and other species can teach us (pp. 253–257). Oxford University Press.Google Scholar
Pietraszewski, D. (2016). How the mind sees coalitional and group conflict: The evolutionary invariances of n-person conflict dynamics. Evolution and Human Behavior, 37, 470–480.Google Scholar
Pietraszewski, D. (2020). Intergroup processes: Principles from an evolutionary perspective. In Van Lange, P., Higgins, E. T., & Kruglanski, A. W. (Eds.), In social psychology: Handbook of basic principles (pp. 373–391). Guilford.Google Scholar
Pietraszewski, D., Curry, O., Peterson, M. B., Cosmides, L., & Tooby, J. (2015). Constituents of political cognition: Race, party politics, and the alliance detection system. Cognition, 140, 24–39.Google Scholar
Pietraszewski, D., & German, T. C. (2013). Coalitional psychology on the playground: Reasoning about indirect social consequences in preschoolers and adults. Cognition, 126, 352–363.Google Scholar
Pietraszewski, D., & Wertz, A. E. (2021). Why evolutionary psychology should abandon modularity. Perspectives on Psychological Science, 1–26. doi: 10.1177/1745691621997113.Google Scholar
Powell, L. J., & Spelke, E. S. (2013). Preverbal infants expect members of social groups to act alike. Proceedings of the National Academy of Science. doi: 201304326.Google Scholar
Puurtinen, M., Heap, S., & Mappes, T. (2015). The joint emergence of group competition and within-group cooperation. Evolution and Human Behavior, 36, 211–217.Google Scholar
Rhodes, M., & Chalik, L. (2013). Social categories as markers of intrinsic interpersonal obligations. Psychological Science, 24, 999–1006.Google Scholar
Rusch, H. (2013). Asymmetries in altruistic behavior during violent intergroup conflict. Evolutionary Psychology, 11, 973–993.Google Scholar
Rusch, H. (2014a). The evolutionary interplay of intergroup conflict and altruism in humans: A review of parochial altruism theory and prospects for its extension. Proceedings of the Royal Society B, 281, 20141539.Google Scholar
Rusch, H. (2014b). The two sides of warfare. Human Nature, 25, 359–377.Google Scholar
Rusch, H., & Gavrilets, S. (2020). The logic of animal intergroup conflict: A review. Journal of Economic Behavior & Organization, 178, 1014–1030.Google Scholar
Russell, S. J., & Norvig, P. (1995). Artificial intelligence: A modern approach. Prentice Hall.Google Scholar
Sandholm, T., Larson, K., Andersson, M., Sherry, O., & Tohmé, F. (1999). Coalition structure generation with worst case guarantees. Artificial Intelligence, 111, 209–238.Google Scholar
Schelling, T. C. (1956). An essay on bargaining. The American Economic Review, 46, 281–306.Google Scholar
Schelling, T. C. (1966). The strategy of conflict. Harvard University Press.Google Scholar
Scott-Phillips, T. C., Dickins, T. E., & West, S. A. (2011). Evolutionary theory and the ultimate-proximate distinction in the human behavioral sciences. Perspectives in Psychological Science, 6, 38–47.Google Scholar
Sedikides, C., Schopler, J., & Insko, C. A. (Eds.). (1998). Intergroup cognition and intergroup behavior. Erlbaum.Google Scholar
Sell, A. N. (2011). The recalibrational theory and violent anger. Aggression and Violent Behavior, 16, 381–389.Google Scholar
Sell, A., Sznycer, D., Al-Shawaf, L., Lim, J., Krauss, A., Feldman, A., … Tooby, J. (2017). The grammar of anger: Mapping the computational architecture of a recalibrational emotion. Cognition, 168, 110–128.Google Scholar
Shaw, A., DeScioli, P., Barakzai, A., & Kurzban, R. (2017). Whoever is not with me is against me: The costs of neutrality among friends. Journal of Experimental Social Psychology, 71, 96–104.Google Scholar
Shaw, M. E. (1981). Group dynamics: The psychology of small group behavior (3rd ed.). McGraw-Hill.Google Scholar
Shehory, O., & Kraus, S. (1998). Methods for task allocation via agent coalition formation. Artificial Intelligence, 101, 165–200.Google Scholar
Shepard, R. N. (1994). Perceptual-cognitive universals as reflections of the world. Psychonomic Bulletin & Review, 1, 2–28.Google Scholar
Sherif, M., Harvey, O. J., White, B. J., Hood, W. R., & Sherif, C. (1961). Intergroup conflict and cooperation: The robbers’ cave experiment. University of Oklahoma Press.Google Scholar
Sherratt, T. M., & Mesterton-Gibbons, M. (2013). Models of group or multi-party contests. In Hardy, I. C. W., & Briffa, M. (Eds.), Animal contests (pp. 33–46). Cambridge University Press.Google Scholar
Simon, H. A. (1969/1996). The sciences of the artificial (3rd ed.). MIT Press.Google Scholar
Smaldino, P., Pickett, C., Sherman, J., & Schank, J. (2012). An agent-based model of social identity dynamics. Journal of Artificial Societies and Social Simulation, 15, 7.Google Scholar
Strayer, F. F., & Noel, J. M. (1986). The prosocial and antisocial functions of preschool aggression. In Zahn-Waxler, C., Cummings, E. M., & Iannotti, R. (Eds.), Altruism and aggression: Biological and social origins (pp. 107–131). Cambridge University Press.Google Scholar
Tajfel, H. (1970). Experiments in intergroup discrimination. Scientific American, 223, 96–102.Google Scholar
Tajfel, H. (1982). Social psychology of intergroup relations. Annual Review of Psychology, 33, 1–39.Google Scholar
Tajfel, H., & Turner, J. C. (1979). An integrative theory of intergroup conflict. In Austin, W. G., & Worchel, S. (Eds.), The social psychology of intergroup relations (pp. 33–47). Brooks/Cole.Google Scholar
Tajfel, H., & Turner, J. C. (1986). The social identity theory of intergroup behavior. In Worchel, S., & Austin, W. G. (Eds.), Psychology of intergroup relations (pp. 7–24). Nelson-Hall.Google Scholar
Tatone, D., Geraci, A., & Csibra, G. (2015). Giving and taking: Representational building blocks of active resource-transfer events in human infants. Cognition, 137, 47–62.Google Scholar
Tooby, J., & Cosmides, L. (1992). The cognitive foundations of culture. In Barkow, J., Cosmides, L., & Tooby, J. (Eds.), The adapted mind: Evolutionary psychology and the generation of culture (pp. 19–136). Oxford Press.Google Scholar
Turner, J. C., Hogg, M. A., Oakes, P. J., Reicher, S. D., & Wetherell, M. S. (1987). Rediscovering the social group: A self-categorization theory. Blackwell.Google Scholar
Ullman, T. D., Spelke, E., Battaglia, P., & Tenenbaum, J. B. (2017). Mind games: Game engines as an architecture for intuitive physics. Trends in Cognitive Sciences, 21(9), 649–665.Google Scholar
Vainstein, M. H., Silva, A. T., & Arenzon, J. J. (2007). Does mobility decrease cooperation? Journal of Theoretical Biology, 244, 722–728.Google Scholar
Von Neumann, J., & Morgenstern, O. (1944). Theory of games and economic behavior. Princeton University Press.Google Scholar
Walter, B. F. (2004). Does conflict beget conflict? Explaining recurring civil war. Journal of Peace Research, 41, 371–388.Google Scholar
Walter, B. F. (2009). Reputation and civil war. Cambridge University Press.Google Scholar
Weiner, B. (1995). Judgments of responsibility: A foundation for a theory of social conduct. Guilford Press.Google Scholar
Whitehouse, H. (2018). Dying for the group: Towards a general theory of extreme self-sacrifice. Behavioral and Brain Sciences, 41, 1–64.Google Scholar
Wilder, D., & Simon, A. F. (1998). Categorical and dynamic groups: Implications for social perception and intergroup behavior. In Sedikides, C., Schopler, J., & Insko, C. A. (Eds.), Intergroup cognition and intergroup behavior (pp. 27–44). Erlbaum.Google Scholar
Worden, L., & Levin, S. A. (2007). Evolutionary escape from the prisoner's dilemma. Journal of Theoretical Biology, 245, 411–422.Google Scholar
Yamagishi, T., Jin, N., & Kiyonari, T. (1999). Bounded generalized reciprocity: Ingroup boasting and ingroup favoritism. Advances in Group Processes, 16, 161–197.Google Scholar