In simple terms
A friendly intro before the formal notes — no formulas yet.
Us vs. Them: The Psychology of Groups
Just being placed in a group changes how we behave — we favour 'us' and can turn against 'them'. Psychologists disagree about WHY: is conflict driven by real competition over resources, or simply by identifying with a group at all? Two famous studies give two answers, and both matter for the exam.
Imagine your school's annual sports day. Everyone in your 'house' (your in-group) works together, cheering each other on to win the trophy. You feel rivalry with the other houses (the out-groups), especially because there is only one trophy — a zero-sum prize. That is competition breeding conflict. But notice something stranger: you probably felt loyal to your house the moment you were sorted into it, before a single race was run. That instant loyalty — with no competition at all — is the puzzle Social Identity Theory tries to solve, while the fight over the single trophy is what Realistic Conflict Theory explains.
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Define the building blocks: in-group, out-group, cooperation, competition, prejudice (attitude) and discrimination (behaviour).
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Explanation 1 — Realistic Conflict Theory: conflict comes from competition over scarce resources (evidence: Sherif's Robbers Cave).
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Explanation 2 — Social Identity Theory: conflict comes from categorising into 'us' and 'them' and seeking a positive social identity (evidence: Tajfel's minimal groups).
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Resolution: superordinate goals and the right kind of contact can turn negative interdependence into cooperation.
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Full topic notes
Formal explanation with the rigour you need for the exam.
Cooperation and competition
Groups can bring out the best and the worst in us. When members share a goal that no one can reach alone, they cooperate: this is positive interdependence — my success is tied to yours. When members chase a prize only one side can win, they compete: this is negative interdependence, and in a zero-sum situation one group's gain is exactly another group's loss. The same people can swing from teamwork to hostility depending purely on how the situation structures interdependence — a central insight of this option, because it means conflict is often about the situation, not about the personalities in it.
Cooperation rests on positive interdependence — outcomes are shared, so helping the group helps you.
Competition rests on negative interdependence — often zero-sum, so the out-group's loss is the in-group's gain.
How a situation is STRUCTURED (shared goal vs single prize) can flip a group between cooperation and conflict without changing who is in it.
Prejudice and discrimination: define them precisely
Examiners penalise students who blur these two terms, so fix them now. Prejudice is an ATTITUDE — a negative, inflexible generalisation about a group. Discrimination is a BEHAVIOUR — treating people unjustly because of their group. Prejudice is the thought; discrimination is the act. The two do not always travel together: a person can hold prejudice yet never act on it, and social norms or laws can produce discrimination even in people without strong personal prejudice. Both are the OUTCOMES we are trying to explain — so the real exam question is: where do they come from?
Prejudice = Attitude. A negative generalisation about a group ('I distrust group X').
Discrimination = Behaviour. Unjust treatment based on group membership ('I refuse to serve group X').
Remember P→A, D→B. They are related but not identical, and either can exist without the other.
Origins — Explanation 1: Realistic Conflict Theory (Sherif)
Realistic Conflict Theory (RCT), developed by Muzafer Sherif, argues that intergroup conflict — including prejudice and discrimination — arises from real competition between groups over scarce and valued resources. Resources can be tangible (territory, money, jobs, prizes) or intangible (status, power). When groups perceive themselves in a zero-sum contest, negative interdependence emerges and hostility follows. The prediction is testable: introduce competition and conflict should appear; remove or override it and conflict should subside.
Supporting study for RCT: Sherif et al. (1954/1961) 'Robbers Cave'
Aim: To test whether competition over scarce resources creates intergroup hostility, and whether superordinate goals can reduce it.
Procedure: 22 well-adjusted 11-year-old boys, strangers to one another, attended a summer camp and were split into two groups (Eagles and Rattlers). Phase 1 (in-group formation): each group bonded separately, forming names, norms and leaders. Phase 2 (friction): the groups met in a tournament where only one team could win prizes — a zero-sum competition. Phase 3 (integration): researchers first tried simple pleasant contact, then introduced superordinate goals (e.g. jointly fixing a 'broken' water supply, pooling money to hire a film).
Findings: Competition rapidly produced hostility — name-calling, flag-burning, raids and refusal to mix. Mere contact did NOT reduce it. Only the superordinate goals, requiring cooperation neither group could manage alone, gradually replaced hostility with cross-group friendships.
Link to theory: The boys had no prior grievances; hostility appeared ONLY once competition was introduced and fell once cooperation was required — exactly as RCT predicts. Conflict was situational, not dispositional.
Origins — Explanation 2: Social Identity Theory (Tajfel & Turner)
Social Identity Theory (SIT) offers a very different origin. It argues that people derive part of their self-concept — their social identity — from the groups they belong to, and are motivated to see those groups (and therefore themselves) positively. Conflict can begin without any competition at all, through three steps: social CATEGORISATION (dividing the world into 'us' and 'them'), social IDENTIFICATION (taking on the in-group's identity), and social COMPARISON (favouring the in-group over the out-group to boost self-esteem). Prejudice and discrimination follow from the drive for a positive social identity, not from any fight over resources.
Supporting study for SIT: Tajfel et al. (1971) minimal groups
Aim: To test whether mere categorisation into groups — with no competition, contact, or history — is enough to produce in-group favouritism.
Procedure: British schoolboys were assigned to two groups on a trivial basis (e.g. supposedly over- vs under-estimating dots, or preferring one abstract painter). Members never met and did not know who else was in their group. Each then allocated points/money to anonymous in-group and out-group members using structured matrices.
Findings: Boys consistently favoured their own group. Strikingly, many chose options that MAXIMISED the DIFFERENCE in favour of the in-group even when this meant their group received less in absolute terms than an alternative — the goal was relative advantage, not raw gain.
Link to theory: With no resources worth fighting over, RCT cannot explain the favouritism. Categorisation ALONE produced discrimination, exactly as SIT predicts — powerful evidence that identity, not competition, can be the origin of intergroup bias.
For a top ERQ, do not just present SIT and RCT side by side — CONTRAST them and use each study as a weapon. Tajfel shows conflict without competition (a problem for RCT); Sherif shows how quickly real competition escalates (something SIT alone underplays). The strongest conclusion is that the two are complementary: identity draws the group boundary, and competition over resources inflames it.
Conflict resolution
If competition creates conflict, cooperation can dismantle it. Sherif's own study showed the route: superordinate goals — objectives both groups want but neither can achieve alone — force cooperation and convert negative interdependence into positive interdependence. Allport's (1954) contact hypothesis adds nuance: contact between hostile groups reduces prejudice only under the right conditions — equal status, common goals, intergroup cooperation, and institutional support. Simple, unstructured contact (as Phase 3 of Robbers Cave first showed) can leave hostility untouched or even worsen it.
Superordinate goals replace 'our win is your loss' with 'we succeed or fail together' — the mechanism that finally reconciled the Eagles and Rattlers.
Contact hypothesis (Allport, 1954): contact reduces prejudice ONLY with equal status, common goals, cooperation and institutional support.
Mere contact is not enough — this is why the early integration attempts in Robbers Cave failed before superordinate goals were introduced.
The effect of group membership on behaviour
Beyond conflict specifically, simply belonging to a group changes how individuals behave. SIT already predicts in-group favouritism, but membership also drives conformity to group norms and deindividuation — the loss of a sense of individual identity and personal responsibility inside a group, which can lower inhibitions against aggression. Zimbardo's (1971) Stanford Prison study is often cited here: ordinary young men assigned the ROLE of guard behaved cruelly within days, suggesting behaviour was shaped by the group role and setting rather than by personality. Use such studies as ILLUSTRATIONS of how membership overrides individual dispositions — and evaluate them (Zimbardo's demand characteristics and ethics are fair critical points) rather than treating them as proof.
In-group favouritism — members reward their own group (SIT).
Conformity to group norms — individuals adjust behaviour to match what the group expects.
Deindividuation — anonymity within a group weakens self-restraint and can increase aggression.
Social roles — Zimbardo (1971) suggests assigned group roles can drive behaviour more than personality, though the study is criticised for demand characteristics and ethics.
Evaluating the explanations and studies
RCT strengths: Robbers Cave has high ecological validity (a real camp, real hostility) and clearly demonstrates cause via its staged phases; it also delivers a practical resolution (superordinate goals).
RCT limitations: Tajfel shows conflict can occur WITHOUT competition, so RCT is not a complete account; Robbers Cave used only 22 boys of one age, gender and culture, limiting generalisability, and raises serious ethical concerns (manufactured harm, minors).
SIT strengths: The minimal group paradigm has strong internal control, isolating categorisation as the cause; SIT explains bias RCT cannot, and generalises across many contexts.
SIT limitations: Artificial tasks (allocating points) have low ecological validity; SIT describes THAT categorisation produces favouritism better than exactly WHY, and can underplay how much real competition intensifies conflict.
Best synthesis: The two are complementary — identity draws the group line (SIT); competition over resources inflames it (RCT). Saying so, and using the studies to justify it, is what reaches the top of Criterion D.
Common mistakes examiners penalise
Confusing prejudice with discrimination — prejudice is an ATTITUDE, discrimination is a BEHAVIOUR. Blurring them signals shaky understanding and costs Criterion B marks.
Getting SIT and RCT the wrong way round — RCT needs competition over resources; SIT needs only categorisation. Tajfel = no competition; Sherif = competition. Mixing these up undermines the whole essay.
Assuming competition is REQUIRED for prejudice — Tajfel's minimal groups show bias with nothing to compete for. Claiming competition is necessary ignores the key counter-evidence.
Describing studies instead of USING them — narrating aim/procedure/findings without linking them to the theory and the question keeps Criterion C out of the top band.
Listing evaluation as a 'shopping list' — dropping unlinked points ('small sample', 'unethical', 'low validity') without developing them or tying them to the argument caps Criterion D.
Relying on a single study — one study, however well explained, caps Criterion C. A top-band essay uses at least two studies as evidence.
Treating mere contact as a cure — contact reduces prejudice ONLY under Allport's conditions (equal status, common goals, cooperation, institutional support); Robbers Cave shows unstructured contact can fail.
Worked examples
See the formulas applied — reveal one step at a time, like the exam.
Using ONE study, explain one origin of intergroup conflict.
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One study explaining an origin of intergroup conflict is Sherif et al.'s (1954) Robbers Cave field experiment, which supports Realistic Conflict Theory.
A manager wants to reduce friction between the Marketing and Sales departments, who constantly blame each other for poor results. Using psychological research, explain one strategy she could use.
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The manager should apply superordinate goals, the resolution strategy demonstrated by Sherif et al. (1954).
Paper 2 ERQ: Discuss the origins of prejudice and/or conflict between groups. [22 marks]
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Model essay
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Group dynamics
The behavioural and psychological processes occurring within a social group (intragroup) or between social groups (intergroup).
Key takeaways
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Cooperation rests on positive interdependence — outcomes are shared, so helping the group helps you.
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Competition rests on negative interdependence — often zero-sum, so the out-group's loss is the in-group's gain.
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How a situation is STRUCTURED (shared goal vs single prize) can flip a group between cooperation and conflict without changing who is in it.
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Get a Paper 2 essay marked: 'Discuss the origins of prejudice and/or conflict between groups. [22]'
Get a Paper 2 essay marked: 'Discuss the origins of prejudice and/or conflict between groups. [22]'
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