Difficulty: Intermediate | Prerequisites: Familiarity with social influence, group dynamics and prejudice (Chapters 9–12 recommended).
This chapter sits at the end of a social psychology course for a reason: it pulls together everything you have learnt about group behaviour, prejudice, aggression and persuasion and asks the practical question, "So how do people actually resolve conflicts?" The material covers why conflicts escalate (social traps, competition, misperception) and what brings hostile parties back to cooperation. If you missed the chapters on prejudice and intergroup relations, skim those first, because the same mechanisms (in-group bias, fundamental attribution error) reappear here in a conflict context. The big payoff is understanding that conflict is not random; it follows predictable social-psychological patterns, which means it can be predicted, managed and sometimes prevented.
Conflict often starts because individuals or groups rationally pursue their own interests, which traps everyone in a worse outcome (the prisoner's dilemma and the tragedy of the commons). Competition over scarce resources, perceived injustice and systematic misperception of the other side's intentions keep conflicts alive. Peace is restored through regulation, communication, smaller groups, changed incentives, superordinate goals and appeals to cooperative norms.
Peace
A condition marked by low levels of hostility and aggression and by mutually beneficial relationships. In simple terms, peace is not just the absence of fighting; it requires that the parties involved are actively better off together.
Social dilemma
A situation in which the most rewarding short-term choice for an individual leads to a collectively poor outcome if everyone makes the same choice. Think of it as: what is smart for one person becomes stupid when everybody does it.
Social trap
A specific form of social dilemma in which conflicting parties, by each rationally pursuing their own self-interest, become caught in mutually destructive behaviour. In simple terms, everyone acts logically on their own, yet the group as a whole ends up worse off.
Prisoner's dilemma
A two-person social trap in which each player must choose to cooperate or defect without knowing the other's choice. Mutual cooperation produces a decent outcome for both; mutual defection produces a poor outcome for both; but unilateral defection is best for the defector and worst for the cooperator. Think of it as: trusting each other pays, but the temptation to cheat is built into the structure.
Tragedy of the commons
The situation that arises when individuals consume more than their fair share of a shared resource, with the cost dispersed across the whole group, until the resource collapses entirely. Classic examples include overfishing, air pollution and groundwater depletion.
Non-zero-sum game (mixed-motive situation)
A game or interaction in which the outcomes need not add up to zero: both sides can win through cooperation, or both can lose through competition. In simple terms, the pie can grow or shrink depending on how people play.
Fundamental attribution error
The tendency to attribute other people's behaviour to their character rather than to the situation they are in. In a conflict context, this means each side sees the other as hostile by nature rather than as responding to the same structural pressures.
Perceived injustice
The subjective sense that one's group is being treated unfairly relative to another group. This perception fuels conflict regardless of whether the injustice is objectively measurable.
Misperception
Systematic distortions in how each side views the other's motives, actions or character. Conflicts are often sustained not by genuine incompatibility of goals but by each side's inaccurate reading of the other.
Social dilemmas as a root of conflict
Many of the biggest threats to collective welfare arise because individuals or groups pursue self-interest rationally
The structural incentive to defect (act selfishly) exists even when cooperation would leave everyone better off
The prisoner's dilemma
Two players, each choosing independently to cooperate or defect
Payoff matrix (classic version): both confess = 5 years each; neither confesses = 1 year each; one confesses while the other stays silent = confessor goes free, silent partner gets 10 years
The rational individual choice (confess) produces a worse collective outcome than mutual cooperation (stay silent)
Demonstrates the fundamental tension at the heart of social conflict: what is individually rational can be collectively destructive
The tragedy of the commons
Individuals take more than their share of a common resource (clean air, water, fisheries, energy, food supplies)
The cost of each person's overconsumption is spread across everyone, so no single person feels the full impact of their own behaviour
Over time, the commons collapses entirely
Classic example: environmental pollution, where the benefit of polluting is private but the cost is public
Both dilemmas share key features
Fundamental attribution error plays a role: each side attributes the other's defection to character ("they're greedy") rather than to the same structural incentive both face
Motives evolve over repeated interactions, sometimes toward more cooperation, sometimes toward deeper distrust
Both are non-zero-sum games: the total outcome depends on the choices made, so both parties can win or both can lose
Many people do adopt a cooperative outlook and expect others to do the same, which enables collective betterment. The lecture identifies five main strategies for encouraging cooperation:
Regulation
External rules that safeguard the common good (e.g. fishing quotas, emissions caps)
Works by removing the temptation to defect: if overuse is penalised, the rational choice shifts toward cooperation
Reducing group size
Smaller groups make each member feel more personally responsible and more connected to the group's success
People identify more strongly with the outcome when they can see their own contribution matters
Effective communication
When parties can talk to each other (unlike the classic prisoner's dilemma setup), cooperation rates rise sharply
Communication builds trust, clarifies intentions and allows promises
Changing the payoffs
Restructure incentives so that cooperation pays better than defection
This is the logic behind carbon taxes, deposit–return schemes and cooperative bonus structures
Appealing to altruistic norms
Reminding people of shared values, fairness and social responsibility
Works because most people carry internalised norms of fairness that can override narrow self-interest when made salient
Competition as a driver of conflict
Hostilities commonly arise when groups compete for scarce resources: jobs, housing, territory
Perceived threats feed prejudice and conflict, and prejudice in turn amplifies the perception of threat (a self-reinforcing cycle)
Sherif's Robbers Cave experiment (Rattlers vs. Eagles): boys' groups placed in win–lose competition quickly developed intense intergroup conflict, negative images of the outgroup, and strong ingroup cohesion and pride
The experiment demonstrates that conflict can be manufactured simply by structuring the situation as zero-sum competition
Perceived injustice
Conflict intensifies when one or both sides feel they are being treated unfairly
The perception of injustice does not need to be objectively accurate to be powerful; the subjective sense of unfairness is enough to fuel hostility
Misperception
Much real-world conflict is sustained by distorted views of the other side
Each party tends to see its own actions as reasonable responses to provocation, while viewing the other side's identical actions as aggressive or hostile
Mirror-image perceptions: both sides hold the same distorted view of each other simultaneously ("we are peaceful, they are aggressive")
Correcting misperceptions is one of the most effective levers for de-escalation
The tragedy of the commons is the framework behind international climate negotiations: each country benefits from industrialising freely, but the atmosphere is shared, so unchecked emissions degrade the resource for everyone. Fishing quotas, water-use treaties and carbon markets are all practical attempts to solve a commons dilemma through regulation and changed payoffs.
Sherif's finding that win–lose competition manufactures hostility is directly relevant to understanding ethnic and national conflicts where groups compete for limited land, political power or economic opportunity. The same dynamic appears in workplace settings where departments compete for a fixed budget.
Students often think the prisoner's dilemma is only about crime. It is a general model for any situation where two parties must choose between cooperation and defection without coordinating, from arms races to business pricing.
Students frequently confuse the prisoner's dilemma with the tragedy of the commons. The prisoner's dilemma is a two-party, one-shot (or repeated) choice; the tragedy of the commons involves many individuals drawing on a shared resource over time.
A common mistake is believing that competition always produces conflict. Competition becomes destructive specifically when it is structured as win–lose (zero-sum). In non-zero-sum situations, competition can coexist with cooperation.
Students sometimes assume perceived injustice requires actual injustice. In social psychology, the perception alone is sufficient to drive conflict, regardless of whether an objective measure would confirm the claim.
⚠️ Be able to read a prisoner's dilemma payoff matrix and identify the dominant strategy, the Nash equilibrium and the cooperative outcome. Exams often present a novel matrix and ask you to reason through it.
⚠️ Know the five strategies for resolving social dilemmas (regulation, small groups, communication, changing payoffs, altruistic norms) and be ready to apply them to a scenario.
⚠️ Sherif's Robbers Cave experiment is a staple exam question. Know the design (two phases: competition, then superordinate goals) and the findings at each stage.
⚠️ Misperception and mirror-image perceptions are frequently tested. Be able to explain how both sides in a conflict can hold the same distorted belief about each other simultaneously.
True or false: In the prisoner's dilemma, mutual cooperation produces the best outcome for each individual player. (False. Unilateral defection produces the best outcome for the defector; mutual cooperation produces the best collective outcome.)
Fill in the blank: The tragedy of the commons occurs when the ______ of overusing a shared resource are dispersed across the group while the ______ are kept by the individual. (costs; benefits)
True or false: Sherif's Robbers Cave experiment showed that mere contact between groups was enough to reduce hostility. (False. Contact alone was not sufficient; superordinate goals were needed.)
Fill in the blank: The tendency to attribute another group's behaviour to their character rather than their situation is called the ______. (fundamental attribution error)
True or false: In a non-zero-sum game, one side's gain must come at the other side's expense. (False. Both sides can gain or both can lose.)
Q: Define a social trap and give one real-world example.
A: A social trap is a situation in which conflicting parties, by each rationally pursuing self-interest, become locked into mutually destructive behaviour. Example: nations in an arms race, where each country arms itself for security, yet the collective result is greater danger and expense for all.
Q: In the classic prisoner's dilemma, why is mutual defection the likely outcome even though mutual cooperation would leave both players better off?
A: Each player's dominant strategy is to defect, because defection yields a better personal outcome regardless of what the other player does. Without the ability to communicate or enforce agreements, rational self-interest drives both toward defection, producing the Nash equilibrium of mutual defection.
Q: Explain two strategies for resolving social dilemmas and describe how each works.
A: (1) Regulation: external rules (laws, quotas, penalties) change the incentive structure so that defection is punished and cooperation becomes the rational choice. (2) Reducing group size: in smaller groups, individuals feel more personally responsible and identify more strongly with the group outcome, which increases voluntary cooperation.
Q: How did Sherif's Robbers Cave experiment demonstrate the role of competition in intergroup conflict?
A: Sherif placed two groups of boys (the Rattlers and the Eagles) in a series of win–lose competitions. The result was rapid development of intergroup hostility, negative stereotyping of the outgroup, and heightened ingroup cohesion and pride, showing that zero-sum competition is sufficient to generate conflict between previously neutral groups.
Q: What is the difference between the prisoner's dilemma and the tragedy of the commons?
A: The prisoner's dilemma involves two parties making a single (or repeated) binary choice to cooperate or defect. The tragedy of the commons involves many individuals continuously drawing on a shared resource. Both illustrate how individual rationality can produce collective harm, but they differ in the number of actors and the nature of the resource at stake.
This chapter connects directly to the material on prejudice and intergroup relations (Chapters 9–10): the same ingroup–outgroup biases that drive stereotyping also fuel conflict escalation. Sherif's work bridges both topics.
The fundamental attribution error, covered in the attribution chapter (Chapter 3), reappears here as a mechanism that sustains conflict: each side misreads the other's behaviour as dispositional rather than situational.
The discussion of altruistic norms ties back to the prosocial behaviour chapter (Chapter 12): the same motivations that drive helping behaviour can also be leveraged to promote cooperation in social dilemmas.
conflict resolution, peace making, peacemaking, social dilemma, social trap, prisoner's dilemma, prisoners dilemma, tragedy of the commons, commons dilemma, non-zero-sum game, mixed-motive situation, zero-sum competition, fundamental attribution error, FAE, attribution bias, perceived injustice, relative deprivation, misperception, mirror-image perception, Sherif, Robbers Cave experiment, Rattlers and Eagles, intergroup conflict, ingroup bias, outgroup hostility, cooperation vs competition, regulation of commons, altruistic norms, superordinate goals, social psychology NYU, Chapter 13 social psych