This chapter explores aspects of individual visions and visionaries that increase the traction to create social change. It begins by examining epistemic gaps – knowledge deficits that inspire visionary ideas – and the role of imagination in addressing these gaps. The chapter then focuses on compelling narratives, discussing the importance of storytelling, relatable characters and moral alignment in crafting transformative visions. It continues by discussing the factors that enable a vision to be spread, such as social identity and network positions that bridge social divides. The chapter also considers how visionary ideas interact with group dynamics and system attributes that facilitate or hinder change. Case studies of William Shakespeare, Martin Luther, and Karl Marx are presented: transformative visions arise from unmet needs; are effective when they offer innovative social relationships; are marked by clear, moral narratives; are more likely to emerge in societies with diverse, autonomous subgroups; and spread via networks of higher trust.

This chapter investigates how advantaged group members perpetuate and deepen inequality, setting the stage for Chapter 4, which addresses their actions to reduce inequality in solidarity with disadvantaged groups. The chapter begins by discussing various forms of material, symbolic and systemic advantages that benefit advantaged groups. It then explores the psychological mechanisms that enable these groups to deny their privilege and engage in competitive victimhood, positioning themselves as aggrieved to justify their entitlement to discriminatory and repressive tactics. Further, this chapter also addresses more extreme manifestations of these behaviours, such as repression, hate crimes, genocide, and colonisation. The psychological processes that sustain these actions, including diffusion of responsibility, system justification, and desensitisation, are discussed. The chapter also considers the intersectional nature of privilege, highlighting how different identities, such as gender and economic status, influence the experience of advantage and perpetration of discrimination and violence.

In this introduction, we highlight the importance of psychological viewpoints to understand the dynamics of how, why and in what way relations between social groups do and do not change. Systems are defined as sets of interconnected elements that form a complex whole that is more than the sum of their parts. This definition underlies our discussions of how social systems change and the resistance to social change through the chapters. In this introduction, the main focus of each chapter is briefly presented, as well as the interconnections between them.

This chapter introduces key themes of the "new psychology" of intergroup relations within systems, highlighting interconnection, intersectionality, temporal cycles, tipping points, and imagination. It challenges the limitations of ‘traditional’ psychology in addressing social change and emphasises the potential of these new approaches. The chapter begins by exploring systems thinking, recognizing that groups are internally divided and externally connected by intersecting identities, so changes within one element affect broader social structures. Intersectionality, critical theories and positioning theory are discussed to understand complex group interactions and power dynamics. The chapter also connects people and groups across time, emphasising the influence of historical context and the importance of future imagination in shaping present actions. It highlights the non-linear nature of social change, marked by tipping points. Finally, the chapter considers humans as part of larger biological and environmental systems, underscoring the interaction between social and physical environments, including the impact of climate change on group identities and norms.

This chapter explores the temporal context of social change, including how scholars have studied changes over time through longitudinal research. It highlights the importance of understanding how the past, present and future interact to shape the attitudes and behaviours of individuals and groups. The chapter reviews key topics such as salience, threat, collective memories and narratives, emphasising their roles in the psychology of groups that act across time and space. Cyclical temporal changes are proposed to be understudied, and the need for comparative, predictive models to better understand recurring rhythms is discussed. The chapter discusses how experiences of the present are influenced by past histories and future anticipations, and the impact of social context on identity salience and intergroup relations. Lastly, the chapter explores how collective futures, including utopias and dystopias, influence motivation and action, exploring the balance of threat and hope in relation to effective collective action.

This chapter explores the concept of networks, discussing their relationship to intergroup relations, system stability, and system change. It reviews emerging research that connects group processes with social network analysis, particularly in the context of attitudes and ideological polarisation. Concepts such as nodes and edges are discussed in relation to how systems can be represented, and theories of influence and change. Drawing from the literature on system stability, we discuss the concepts of homeostatic mechanisms (mechanisms that seek to preserve stability) and resilience (the preservation of systems in the face of disruptions), and link these to the literatures in Part 1 on identities, groups, social influence, and collective actions.

This chapter explores the role of ideologies (i.e., socially shared belief systems) to justify or challenge existing social systems. The chapter begins by defining ideologies and examining their origins, focusing on how they are shaped by socialisation, collective identities, and power relations. It then discusses system-justifying ideologies, such as right-wing authoritarianism, social dominance orientation and belief in a just world, which legitimise inequality and attribute privilege to merit. In contrast, the chapter also explores system-change ideologies that challenge inequality and promote social change, focusing on the psychological processes that lead advantaged group members to embrace these ideologies and become allies. Psychological dynamics underlying allyship and solidarity are also discussed. In sum, the chapter highlights the complexities of allyship, noting that motivations can vary and that intersectional privileges can either foster or undermine solidarity, depending on shared identities and norms within groups.

This chapter explores the dynamics of non-linear changes within social systems, focusing on the processes that lead to societal collapse and ‘emergence’ (when a new social order forms that is qualitatively different from the past). The chapter first reviews the forces that create stability, differentiation, and oscillation. The DIME model is introduced, which explores how activists choose tactics to follow up the success or failure of their collective action. The chapter explores dynamics of intergroup contestation, including polarisation and backlash that drive systems towards either emergence or collapse. System stability is supported through coordinated identities and norm sequences that are often localised spatially, which act as homeostatic mechanisms to create resilient systems. However, behavioural changes manifest as actors establishing new cues and framing collective actions in ways that channel energy towards new identities and norms. Finally, the chapter explores mutual radicalisation, where mutual feedback loops of failure and threat signals between groups drive radicalisation, reinforcing intergroup tensions.

This chapter introduces the dynamics of ecosystems and chaotic systems, providing an accessible overview for readers unfamiliar with complexity theory. Key concepts such as fractals and emergence are defined and applied to social groups through the FLINT model of Factional Leadership, Intergroup Conflict, Norms, and Time, which explains how factions and subgroups form and ferment within a seemingly unified group. This model examines forces driving subgroup differentiation and the challenges of achieving lasting social change because of the need to influence multiple groups simultaneously and overcome resistance. The chapter revisits psychological research on effective activism, underscoring the importance of addressing both conformity and dissent within and between groups. Finally, we discuss empirical methods for analysing these complex dynamics, including network analyses, person-centred analyses, and agent-based modelling, which offer new ways to understand and study the formation and evolution of groups.

This chapter synthesises the key themes of the book, focusing on how the new psychology of intergroup relations advances our understanding of social change. The chapter first summarises how the new approach enhances traditional theories and methods, highlighting the role of place, time and change in group processes and intergroup relations. Multi-group dynamics create a complex system which is marked by intersectionality, and the interplay of stability, conflict and innovation. Further, the chapter explores how individuals and groups can engage with the new psychology of system change. It stresses the importance of altering relationships, understanding pushback and articulating shared visions to address collective threats with effective solutions. The need for enhanced perception of latent forces in social and physical environments is emphasised, alongside the call for connecting knowledge and power across mainstream institutions. The chapter considers how readers can be equipped to understand and effect change locally and globally, and to see and intervene in the broader socio-ecological system.

The chapter begins by examining how groups form and socialise members, and the forces of conformity that sustain existing norms. We then consider the emergence of differentiation and innovation, exploring how processes of minority influence and dissent challenge conformity. The chapter then explores the impact of contested norms, particularly in systems of inequality, and considers how these norms are challenged and transformed under more repressive and open regimes. This chapter also explores power, repression, agency and resistance, and how reinterpretations of classical studies by Milgram and Zimbardo are now understood through the lens of social identity theory. The transmission of norms between groups is discussed, alongside the entrepreneurs of identity who mobilise advantaged groups to support disadvantaged groups. This chapter makes a transition from traditional theories of intergroup relations to new paradigms that emphasise the fluidity of norms, the role of emerging leadership, and the transformative potential of identity in group dynamics.

This chapter examines how groups respond to disadvantage, beginning with a discussion of the various ways intergroup inequality manifests across three levels: material (e.g. violence, segregation), symbolic (e.g., stereotypes, devaluation), and systemic (e.g., biased judicial systems). The chapter emphasises the real and diverse impacts of these disadvantages on everyday lives. Further, this chapter explores individual and collective reactions to disadvantage, from acceptance and minimisation to social mobility and reappraisal of group differences. Collective responses, such as social creativity and mobilisation, are highlighted as vital for resilience and social change. The factors are discussed that influence disadvantaged groups’ choice of responses, including individual factors, social support and ‘intersectionalities’ – being part of multiple groups. The chapter also suggests that individual and societal levels of analysis influence internal group dynamics and the effectiveness of collective actions.