Social solidarity is the sense of mutual attachment, shared responsibility and collective commitment that connects people within a group, community or society. It concerns the forces that hold people together despite differences in interests, identities, occupations, beliefs or circumstances. The concept is strongly associated with Émile Durkheim, who used solidarity to analyse how societies maintain cohesion.
Durkheim distinguished mechanical solidarity, associated with relatively similar forms of life and shared beliefs, from organic solidarity, associated with differentiated societies in which people depend upon one another through specialised roles. Modern uses of the concept are broader and can refer to mutual aid, collective responsibility, social integration, support for disadvantaged groups and willingness to contribute to shared institutions. Solidarity therefore concerns relationships of social obligation rather than merely emotional friendliness.
Durkheim's distinction between mechanical and organic solidarity remains influential because it illustrates two different bases of social cohesion. Mechanical solidarity arises when members of a community share relatively similar occupations, beliefs, values and ways of life, producing cohesion through perceived similarity. Organic solidarity develops when social differentiation increases and people perform specialised roles that make them mutually dependent. In a complex economy, for example, individuals depend on numerous other occupations even though they do not share the same daily experiences.
Durkheim argued that modern cohesion therefore does not require everyone to be alike. Interdependence can itself create social bonds. However, organic solidarity depends on institutions and norms that allow differentiated roles to function fairly. If social arrangements become severely unequal or people perceive relationships as exploitative, interdependence may not produce a stable sense of solidarity.
Social solidarity can operate through shared identity, common values, mutual dependence and collective responsibility. People may feel solidarity because they identify as members of the same nation, community, occupation, religion, movement or social group. Shared experiences of hardship can also generate solidarity by creating a sense of common fate. Mutual dependence provides another basis because people recognise that their wellbeing is connected to the contributions of others.
Collective responsibility extends this idea by treating certain social problems as matters that should be addressed jointly rather than left entirely to individuals. Solidarity can therefore involve emotional attachment, practical assistance, institutional arrangements and moral obligations. The balance among these elements varies between societies and groups.
Solidarity is expressed through both formal institutions and informal practices. Welfare systems, public healthcare, social insurance, collective bargaining, mutual aid associations and community organisations can institutionalise principles of shared responsibility. Informal solidarity appears through neighbours helping one another, families supporting relatives, communities organising assistance and individuals contributing to collective efforts. During crises, solidarity may become particularly visible when people coordinate resources, provide practical support or accept temporary restrictions for collective purposes.
Institutional solidarity can make support more predictable and distribute risks across large populations, while informal solidarity can respond flexibly to local needs. Both forms depend on norms of reciprocity and shared responsibility, although solidarity can sometimes involve helping people without expecting a direct return because members perceive a broader collective obligation.
Social solidarity has an important relationship with social inequality. High inequality can weaken solidarity when people inhabit substantially different social worlds and believe that institutions distribute opportunities or burdens unfairly. Conversely, solidarity can motivate efforts to reduce inequality by encouraging support for social insurance, public services and collective provision. Solidarity does not necessarily require equal outcomes, but it generally involves some recognition that people have obligations toward one another.
Political and social movements often use solidarity to connect individual experiences to collective demands. Workers may organise around shared occupational interests, while communities may mobilise around shared experiences of discrimination or disadvantage. Such solidarity can increase collective power, but it can also produce boundaries between insiders and outsiders if the collective identity is defined narrowly.
Social solidarity is closely related to social cohesion, social integration, social trust, cooperation and collective identity, but each concept emphasises something different. Social cohesion concerns the overall quality and stability of relationships within a society. Social integration concerns incorporation into social structures and networks. Social trust concerns expectations that others will behave reliably. Cooperation concerns coordinated action toward compatible goals. Collective identity concerns shared self understanding as members of a group. Solidarity adds the idea of mutual commitment and responsibility. A society may have frequent interaction without strong solidarity if people do not feel obligations toward one another. Conversely, solidarity can motivate collective action even when relationships between participants are not personally close.
Solidarity can be inclusive or exclusive. Inclusive solidarity extends concern across social differences and recognises people as members of a broader collective, while exclusive solidarity prioritises obligations to a narrower group. Strong internal solidarity can therefore coexist with distrust or hostility toward outsiders. National solidarity, for example, can encourage mutual responsibility among citizens while creating debates about obligations toward non citizens. Occupational, religious or cultural solidarity can similarly provide strong support within a group but may produce boundaries around membership.
This does not mean solidarity is inherently exclusionary. Broad identities and universal principles can expand the scope of solidarity, while institutions can establish rights and responsibilities that apply across different groups. The scope of solidarity is therefore a major question in analysing its social consequences.
Solidarity is significant because complex societies require mechanisms for managing interdependence. People routinely depend on strangers for healthcare, education, transport, food production, infrastructure, communication, security and other services. Solidarity provides a social and moral framework for recognising these connections and distributing responsibilities and risks. It can strengthen resilience during crises, support collective action and make institutions more legitimate when people perceive them as expressions of shared responsibility.
At the same time, solidarity can be weakened by exclusion, severe inequality, polarisation, institutional failure and perceptions of unfairness. Sustainable solidarity generally requires both shared principles and credible institutions that allow people to see themselves as participants in a common social system. It is therefore not simply a feeling of togetherness but a broader pattern of mutual obligation, recognition, support and collective commitment.
