Social dominance theory (SDT) is a social psychological theory of intergroup relations that examines the caste-like features of group-based social hierarchies, and how these hierarchies remain stable and perpetuate themselves. According to the theory, group-based inequalities are maintained through three primary mechanisms: institutional discrimination, aggregated individual discrimination, and behavioral asymmetry. The theory proposes that widely shared cultural ideologies ("legitimizing myths") provide the moral and intellectual justification for these intergroup behaviors by serving to make privilege normal. For data collection and validation of predictions, the social dominance orientation (SDO) scale was composed to measure acceptance of and desire for group-based social hierarchy, which was assessed through two factors: support for group-based dominance and generalized opposition to equality, regardless of the ingroup's position in the power structure.
The theory was initially proposed in 1992 by social psychology researchers Jim Sidanius, Erik Devereux, and Felicia Pratto. It observes that human social groups consist of distinctly different group-based social hierarchies in societies that are capable of producing economic surpluses. These hierarchies have a trimorphic (three-form) structure, a description which was simplified from the four-part biosocial structure identified by van den Berghe (1978). The hierarchies are based on: age (i.e., adults have more power and higher status than children), gender (i.e., men have more power and higher status than women), and arbitrary-set, which are group-based hierarchies that are culturally defined and do not necessarily exist in all societies. Such arbitrariness can select on ethnicity (e.g., in the US, Bosnia, Asia, Rwanda), class, caste, religion (Sunni versus Shia Islam), nationality, or any other socially constructed category. Social hierarchy is not only seen as a universal human feature – SDT argues there is substantial evidence it is shared, including the theorized trimorphic structure – among apes and other primates. Personal level According to researchers, individuals who score high on the psychological tendency known as social dominance orientation are more likely to support discriminatory policies and the hierarchical organization of the social world. Individuals with high levels of social dominance orientation are also more inclined to endorse ideologies such as racism, sexism, homophobia, nationalism, and militarism. Theorists argue that social dominance orientation is a psychological tendency that has developed through evolutionary processes and is present, to varying degrees, in all individuals.
Group level
Group hierarchy Social dominance theory (SDT) argues that all human societies form group-based hierarchies. A social hierarchy is where some individuals receive greater prestige, power or wealth than others. A group-based hierarchy is distinct from an individual-based hierarchy in that the former is based on a socially constructed group such as race, ethnicity, religion, social class and freedoms, linguistic group, etc. while the latter is based on inherited, athletic or leadership ability, high intelligence, artistic abilities, etc.
A primary assumption in social dominance theory (SDT) is that racism, sexism, nationalism, and classism are all manifestations of the same human disposition to form group-based social hierarchies. The social tiers described by multiple intersectional theories of stratification become organized into hierarchies due to forces that SDT believes are best explained in evolutionary psychology to offer high survival value. Human social hierarchies are seen to consist of a hegemonic group at the top and negative reference groups at the bottom. More powerful social roles are increasingly likely to be occupied by a hegemonic group member (for example, an older white male). Males are more dominant than females, and they possess more political power and occupy higher status positions illustrating the iron law of androcracy. As a role gets more powerful, Putnam's law of increasing disproportion becomes applicable and the probability the role is occupied by a hegemonic group member increases.
SDT adds new theoretical elements attempting a comprehensive synthesis of explanations of the three mechanisms of group hierarchy oppression that are regulated by legitimizing myths:
Aggregated individual discrimination (ordinary discrimination) Aggregated institutional discrimination (by governmental and business institutions) State terrorism (e.g., police violence, death squads) Behavioural asymmetry Deference–systematic outgroup favouritism (minorities favour members of dominant group) asymmetric ingroup bias (as status increases, in-group favoritism decreases) self-handicapping (self-categorization as an inferior becomes a self-fulfilling prophecy) ideological asymmetry (as status increases, so do beliefs legitimizing and/or enhancing the current social hierarchy)
Although the nature of these hierarchical differences and inequality differs across cultures and societies, significant commonalities have been verified empirically using the social dominance orientation (SDO) scale. In multiple studies across countries, the SDO scale has been shown to correlate robustly with a variety of group prejudices (including sexism, sexual orientation prejudice, racism, nationalism) and with hierarchy-enhancing policies.
Social dominance theory also emphasizes that group-based hierarchies are closely tied to the distribution of resources, opportunities, and social status within a society. These hierarchies tend to privilege dominant groups while systematically disadvantaging subordinate groups, often in ways that are not explicitly recognized or acknowledged. As a result, individuals may experience unequal access to education, healthcare, and economic opportunities depending on their position within the social structure.
The theory further suggests that these hierarchical divisions are influenced by a variety of social categories, including race, gender, religion, age, and economic status. These categories shape how individuals are grouped within society and determine their relative access to power and privilege. Importantly, such hierarchies are not always consciously constructed, but may instead emerge through long-standing social practices and cultural norms.
Another key aspect highlighted in the literature is that social dominance hierarchies are nearly universal across human societies, although their specific forms and determining factors may vary depending on cultural and historical context. This universality suggests that hierarchical organization is a recurring feature of social systems, even though the criteria for dominance differ across societies.
Additionally, the theory draws attention to the role of social structures in maintaining inequality over time. Once established, hierarchies can shape individuals' life trajectories by influencing their perceived social status, access to resources, and opportunities for upward mobility. This process contributes to the persistence of inequality and reinforces existing social divisions across generations. Behavioural asymmetry
According to the theory, group-based inequalities are also shaped by interactions between groups. Behavioural asymmetry refers to the tendency of members of dominant and subordinate groups to exhibit different patterns of behaviour, which can facilitate greater access to resources for dominant groups. Several forms of behavioural asymmetry have been identified. Asymmetric ingroup bias reflects the tendency of dominant group members to favour their own group more strongly than subordinate group members. In some cases, members of subordinate groups may even display outgroup favouritism toward dominant groups.
Another mechanism associated with subordinate groups is self-handicapping behaviours, which may contribute to the maintenance of inequality. These include behaviours such as substance use, intragroup violence, or engagement in unlawful activities that may harm the ingroup. Such behaviours can reinforce existing stereotypes directed at subordinate groups.
Finally, members of dominant groups are more likely to adopt ideologies, beliefs, attitudes, and behaviours that support the maintenance of hierarchical systems. All else being equal, they are also more likely to score higher on social dominance orientation, which facilitates the continuation of social hierarchies in their favour. This process is referred to as ideological asymmetry. Legitimizing myths theory SDT believes that decisions and behaviors of individuals and groups can be better understood by examining the "myths" that guide and motivate them. Legitimizing myths are consensually held values, attitudes, beliefs, stereotypes, conspiracy theories, and cultural ideologies. Examples include the inalienable rights of man, divine right of kings, the protestant work ethic, and national myths. In current society, such legitimizing myths or narratives are communicated through platforms like social media, television shows, and films, and are investigated using a variety of methods including content analysis, semiotics, discourse analysis, and psychoanalysis. The granularity of narrative extends from broad ideologies at the highest level to middle level personal myths (positive thinking of oneself as a successful smart dominant, or submissive inferior), reaching the lowest level of behavioral scripts or schemas for particular dominant-submissive social situations. Categories of myth include: paternalistic myths (the dominant hegemony serves society, looks after incapable minorities) reciprocal myths (suggestions that dominants and outgroups are actually equal) sacred myths (karma or divine right of kings as a religion-approved mandate to dominate others)
For regulation of the three mechanisms of group hierarchy oppression, there are two functional types of legitimizing myths: hierarchy-enhancing and hierarchy-attenuating myths. Hierarchy-enhancing ideologies (e.g., racism or meritocracy) contribute to greater levels of group-based inequality. Felicia Pratto presented meritocracy as an example of a legitimizing myth, and how the myth of meritocracy produces only an illusion of fairness. Hierarchy-attenuating ideologies such as protected rights, universalism, egalitarianism, feminism, and multiculturalism contribute to greater levels of group-based equality. People endorse these different forms of ideologies based in part on their psychological orientation to accept or reject unequal group relations as measured by the SDO scale. People who score higher on the SDO scale tend to endorse hierarchy-enhancing ideologies, and people who score lower tend to endorse hierarchy-attenuating ideologies. Finally, SDT proposes that the relative counterbalance of hierarchy-enhancing and -attenuating social forces stabilizes group-based inequality.
Interactions with authoritarian personality theory