Social Psychology
Prosocial Behavior
Helping, sharing, cooperating — and why we sometimes don't
Prosocial behavior is action intended to benefit others — helping a stranger, donating, cooperating, comforting. Altruism is the subset done without expectation of reward. The Kitty Genovese murder (1964) prompted Latane and Darley's bystander effect research showing people help less when others are present, due to diffusion of responsibility and pluralistic ignorance. Daniel Batson's empathy-altruism hypothesis argues genuine altruism exists when empathy is felt; otherwise helping is egoistic. Toddlers help spontaneously by 14 months (Warneken and Tomasello), suggesting prosocial tendencies are partly innate.
- Major researcherBibb Latane and John Darley (bystander effect)
- Trigger eventKitty Genovese murder (1964, New York)
- Diffusion of responsibilityMore bystanders → less individual help
- Empathy-altruismDaniel Batson — genuine altruism via empathy
- DevelopmentalHelping by 14 months (Warneken and Tomasello)
- Cross-culturalUniversal but culturally moderated by ingroup vs outgroup
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Why prosocial behavior matters
- Emergency response. Bystander training counters diffusion of responsibility.
- Charity fundraising. Identifiable victims raise more than statistics.
- Workplace cooperation. Reciprocity and ingroup framing build teams.
- Public health. Vaccination, blood donation, organ donation depend on it.
- Education. Cooperative learning improves outcomes via prosocial norms.
- Conflict resolution. Empathy induction reduces intergroup hostility.
- Evolutionary biology. Kin selection and reciprocity explain cooperation across species.
Common misconceptions
- True altruism is impossible. Batson's experiments support genuine altruism via empathy.
- People are basically selfish. Spontaneous helping appears in toddlers worldwide.
- More witnesses means more help. Bystander effect: more often means less help.
- Genovese is the proof. The case was misreported; the science is from Latane-Darley experiments.
- Helping always feels good. Costly helping can produce stress, regret, compassion fatigue.
- Prosocial behavior is purely cultural. Evolutionary roots (kin selection, reciprocity) operate across species.
Frequently asked questions
What's the bystander effect?
People are less likely to help in emergencies when others are present. Latane and Darley (1968) staged emergencies — smoke filling a room, a confederate having a seizure — and found that with one observer, help came quickly; with five, it often didn't come at all. Two mechanisms: diffusion of responsibility (someone else will act) and pluralistic ignorance (others' inaction signals the situation isn't an emergency).
Was Kitty Genovese the textbook story?
Partially. The 1964 New York Times reported 38 witnesses watched her murder without acting. Later analysis showed the number was inflated; some did call police. But the case sparked Latane and Darley's research, which established the bystander effect as real even if Genovese's specific case was misreported. The myth and the real phenomenon are now usefully separated.
What's the empathy-altruism hypothesis?
Daniel Batson's claim that empathy produces genuinely altruistic motivation — concern for the other's welfare for its own sake. His experiments offered easy escape from helping; without empathy, people fled; with induced empathy, they stayed and helped even when escape was easy. Critics propose alternative egoistic explanations (mood-elevation, aversive arousal reduction) but Batson's experimental designs increasingly rule them out.
How early does helping appear?
Warneken and Tomasello (2006) showed 14- to 18-month-olds spontaneously help adults who drop objects or struggle to open doors. The toddlers had not been trained or reinforced. Chimpanzees show similar instrumental helping, suggesting the foundation predates human-specific culture. Sharing food and comforting emerge slightly later. By age 2, sharing increases when watched — reputation effects begin early.
What's kin selection?
Hamilton's (1964) inclusive fitness theory: helping kin promotes shared genes. Hamilton's rule — help if r·b > c (relatedness times benefit exceeds cost) — predicts more help to closer relatives. Field studies confirm: humans help siblings more than cousins, run into burning buildings for children more than acquaintances. This is the evolutionary scaffold under prosocial behavior, though humans extend it well beyond kin.
What's reciprocal altruism?
Trivers (1971) — helping an unrelated other pays off if they help you back later. Vampire bats share blood with non-kin who shared with them. Humans extensively cooperate with strangers via reputation, repeated interactions, and institutions. Reciprocal altruism explains why even economic strangers help, especially in repeated games. Tit-for-tat, the simplest reciprocal strategy, wins many evolutionary tournaments.
How can prosocial behavior be increased?
(1) Reduce diffusion — designate specific people ("you in the red shirt, call 911"). (2) Model helping — observed prosociality is contagious. (3) Increase identifiability — single victims attract more help than statistics ("identifiable victim effect"). (4) Build empathy via perspective-taking. (5) Foster ingroup framing across boundaries. (6) Public recognition exploits reputation incentives. (7) Reduce time pressure — Darley and Batson's "Good Samaritan" study found rushed seminarians stepped over a confederate.