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Key points
- In-group affiliation can boost self-esteem and support social cohesion within the group.
- Out-groups are seen as threats, driving division and conflict.
- Counter cognitive biases and collaborate between groups to foster understanding and connection.
Human beings need to belong. From our earliest cave-dwelling ancestors, membership in a clan or tribe was a requirement for survival. Group membership provided safety, resources, and shared knowledge.
While physical survival in the 21st century is much less dependent on group affiliation, the psychological mechanisms driving clustering into "in-groups" and "out-groups" persist. Distinctions between and within groups shape social behavior, influence identity, fuel intragroup collaboration, and power intergroup conflict. Social psychology, evolutionary theory, and cognitive neuroscience have insights into in-group and out-group dynamics.
What Works Against Empathy?
Understanding that other people have “intentions, desires, beliefs, perceptions, and emotions” that differ from ours is a key step to building empathy and relationships. (You can read more about "Theory of Mind" here.)
Psychological Underpinnings of In-Group and Out-Group Formation
The division between in-groups and out-groups is a process of categorization, a fundamental cognitive function. We classify plants as edible or poisonous, tools as useful or broken, and people as friends or foes.
Social identity theory, introduced by Henri Tajfel, posits that individuals derive a sense of self from group affiliation. Group memberships form part of a person’s social identity, influencing self-esteem and providing a framework for understanding the world.
One of the central tenets of social identity theory is that we strive for positive distinctiveness. Differentiation fosters feelings of cohesion within the in-group and exclusion toward the out-group. We bolster the status of our in-group by favorably comparing them to out-groups. Out-groups are often perceived as being inferior or threatening. For example, “My group is refined. Yours is coarse or common.” Or, “My group is hardworking. Your group is lazy.”
Marking my group with badges of distinction enhances self-esteem and creates a sense of belonging. By identifying with a specific group, members can feel part of something larger than themselves.
Evolutionary Roots of Group Dynamics
The division of people into in-groups and out-groups has deep evolutionary roots. Humans who banded together in groups were more likely to survive and have reproductive success. Group membership enabled more secure access to resources and safety against predators. People outside the group—out-group members—were potential threats. This dichotomy between “us” and “them” became an asset.
Favoring in-group members and suspicion of out-group members was an adaptive strategy. In-group cooperation maximized the chances of survival for individuals and their offspring. Suspicion and avoidance of out-groups minimized the risk of conflict. These strategies continue into modern times. Many of us exhibit loyalty to sports teams, colleges, political parties, ideologies, consumer brands, or cultural groups in patterns that echo ancient behaviors despite the absence of any real physical threat.
Cognitive Biases and Group Perception
The human brain is wired to seek patterns (categorization). In-group and out-group dynamics fit neatly into our drive to categorize our experience. Is this person a member of my group or a different group?
Cognitive biases, including confirmation bias, reinforce slotting people into in-group or out-group membership. Confirmation bias means we selectively focus on characteristics or information that confirms existing beliefs about in-groups and out-groups. For example, suppose you believe your in-group is more trustworthy than an out-group. In that case, you are more likely to notice instances that support this belief (say, a newspaper article about cheating) while disregarding or discounting evidence to the contrary.
The out-group homogeneity effect is another cognitive bias contributing to in-group/out-group sorting. In this bias, in-group members are viewed with nuance as individuals with distinct traits and personalities, while members of out-groups are perceived as more similar to each other than they truly are. The result can be stereotyping and, in extreme cases, dehumanization when out-group members are reduced to a few defining characteristics.
Yet another cognitive bias, social comparison, amplifies group identity. When individuals assess their worth by comparing their group to others, disparagement of the out-group enhances the status of the in-group. Belonging to the superior group reinforces group loyalty and strengthens the perceived division between "us" and "them."
The Role of Culture and Socialization
While evolutionary and cognitive factors provide the foundation for in-group and out-group dynamics, cultural influences play a significant role. From an early age, we are socialized into specific groups, absorbing norms, values, and expectations that define in-group behavior. Socialization helps us understand what behaviors are expected and acceptable, who belongs within our group, and who is excluded.
Cultural and societal narratives can exacerbate in-group and out-group divisions. Many conflicts—whether based on ethnicity, ideology, religion, or nationality—have been fueled by narratives emphasizing the inherent differences between groups. These cultural scripts reinforce in-group solidarity and can justify the marginalization or exclusion of out-groups
In 2024, algorithms are potent shapers of group dynamics. Social media, for example, often encourages echo chambers, where people predominantly interact with others who share their beliefs while vilifying out-groups. In environments driven by anger and outrage, the divide between in-groups and out-groups grows.
Consequences of In-Group and Out-Group Division
Group membership can foster a sense of belonging and enhance self-esteem. It also has darker implications. In-group/out-group dynamics contribute to social fragmentation and discrimination. Political polarization, for example, is often driven by strong alignment within groups and the belief that those who belong to the opposing political camp are fundamentally different or morally inferior. It is challenging to sustain constructive dialogue and cooperation without social cohesion.
The psychological processes that bind individuals to in-groups can lead to discrimination, prejudice, and even violence against people who belong to out-groups. In-group favoritism and out-group derogation have fueled, and continue to fuel, intergroup conflict, from tribal warfare to genocides.
Group Affiliation: A Positive Alternative to “Bowling Alone”
While the formation of in-groups and out-groups does create division and conflict, the absence of strong social bonds—what political scientist Robert Putnam termed the “Bowling Alone” phenomenon—is also detrimental to well-being. The Bowling Alone concept refers to declining social capital in modern societies, with individuals disconnected from civic organizations, religious groups, or even casual social gatherings.
Low participation rates in collective experiences lead to isolation and reduced social support. Research shows that social connections are essential for mental health. Feelings of belonging and purpose are essential building blocks for emotional resilience. The erosion of social networks presents significant risks, leaving individuals isolated and society less cohesive; healthy individuals and robust societies balance group affiliations with inclusive, connected communities.
Building Healthier Group Affiliation
Understanding what drives sorting into in-groups and out-groups is the first step to mitigating the negative consequences of these divisions and leveraging the potential positive benefits of sorting. Interventions encouraging empathy and shared goals can reduce bias and foster social harmony. Research demonstrates that when individuals collaborate with out-group members toward a common objective, the perception of difference diminishes, and intergroup relations improve. Even the simple step of meeting in person can carry benefits (as anyone who has experienced meeting colleagues in person rather than on Zoom can attest).
Reducing the harmful effects of in-group and out-group dynamics requires addressing the underlying cognitive biases and encouraging critical reflection on our social identity. Encouraging empathy toward out-groups, challenging stereotypes, and promoting cross-group interactions can help dismantle harmful divisions and promote a more cohesive society.
Conclusion
The division of individuals into in-groups and out-groups is a complex phenomenon rooted in cognitive, evolutionary, and cultural processes. While these dynamics offer psychological benefits, such as a sense of belonging and identity, they contribute to conflict, discrimination, and social fragmentation. By recognizing the psychological mechanisms underlying group divisions and fostering inclusive practices, individuals and societies can work toward reducing the negative impacts of in-group and out-group categorization.
© 2024 Dr. Fabiana Franco. All rights reserved.
References
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Dreu, C., & Kret, M. (2016). Oxytocin Conditions Intergroup Relations Through Upregulated In-Group Empathy, Cooperation, Conformity, and Defense. Biological Psychiatry, 79, 165-173. https://doi.org/10.1016/j.biopsych.2015.03.020.
Dreu, C., & Kret, M. (2016). Oxytocin Conditions Intergroup Relations Through Upregulated In-Group Empathy, Cooperation, Conformity, and Defense. Biological Psychiatry, 79, 165-173. https://doi.org/10.1016/j.biopsych.2015.03.020.
Molenberghs, P. (Ed.). (2022). The Neuroscience of Intergroup Relations: Global Perspectives on the Neural Underpinnings of Intergroup Behaviour, Ingroup Bias and Prejudice (1st ed.). Routledge. https://doi.org/10.4324/9781003042426
Putnam, R. D. (2015). Bowling alone: America’s declining social capital. In The city reader (pp. 188-196). Routledge
Turner, J., Sachdev, I., & Hogg, M. (1983). Social categorization, interpersonal attraction and group formation. British Journal of Social Psychology, 22, 227-239. https://doi.org/10.1111/J.2044-8309.1983.TB00587.X.
