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Unlock This CourseHave you ever noticed how you're more likely to help someone wearing your school uniform than a stranger from another school? Or how football fans will help each other during matches but ignore supporters from rival teams? This is Social Identity Theory in action - one of the most important explanations for why we help some people more than others.
Social Identity Theory, developed by Henri Tajfel and John Turner in the 1970s, explains how our sense of who we are is largely based on the groups we belong to. This theory suggests that we don't just see ourselves as individuals, but as members of various social groups - and this dramatically affects our helping behaviour.
Key Definitions:
We naturally favour members of our own groups. This means we're more likely to help, trust and show kindness to people we see as "one of us". This isn't necessarily conscious - it happens automatically when we categorise people as part of our group.
The core idea is simple: when we share an identity with someone, we're much more likely to help them. This happens because we extend our sense of self to include other group members. Their success becomes our success, their problems become our problems.
Social Identity Theory identifies three main psychological processes that explain how shared identity leads to helping behaviour:
We automatically sort people into groups - "us" and "them". This happens instantly based on visible cues like clothing, accent, or behaviour. Once we've categorised someone as part of our group, we're primed to help them.
We adopt the identity of groups we belong to. The stronger our identification with a group, the more we're willing to help other group members. A passionate Manchester United fan will go to great lengths to help fellow supporters.
We compare our groups to others, seeking positive distinctiveness. Helping in-group members whilst ignoring out-group members reinforces our group's superiority and strengthens our positive social identity.
During the 2005 London terrorist attacks, strangers helped each other escape from underground stations and buses. Witnesses reported that people didn't ask about each other's backgrounds - they simply saw fellow Londoners in need. The shared identity of being "Londoners under attack" created an immediate bond that triggered widespread helping behaviour, regardless of usual social divisions.
Several important studies have demonstrated how shared identity influences helping behaviour. These experiments show that even the smallest group memberships can dramatically change how we treat others.
Henri Tajfel conducted groundbreaking experiments in the 1970s that showed how easily group favouritism develops. He created completely artificial groups by randomly assigning participants to teams based on trivial preferences (like preferring paintings by Klee or Kandinsky). Even though these groups were meaningless, participants consistently favoured their own group members when distributing rewards.
What this showed: We don't need meaningful connections to show in-group favouritism. Simply being told we belong to the same group as someone else is enough to trigger helping behaviour.
Mark Levine conducted a clever experiment using Manchester United football fans. Participants were asked to walk to another building, but on the way, they encountered someone who had fallen and was calling for help. The key manipulation was what the person in need was wearing:
Results: Participants were much more likely to help when the person wore a Manchester United shirt. They largely ignored the person in the Liverpool shirt, showing how shared identity directly influences helping behaviour.
Researchers Samuel Gaertner and John Dovidio extended Social Identity Theory by suggesting that we can reduce prejudice and increase helping by creating a shared, overarching identity. Instead of seeing "us vs them", we can create a bigger "us" that includes everyone.
Different year groups might compete with each other, but when the school competes against another school, all students unite under their shared school identity. This explains why school sports days create such strong feelings of unity and mutual support.
Not all group memberships are equally powerful. Several factors determine how strongly shared identity influences helping behaviour:
How obvious or important the group membership is in that moment. Wearing team colours makes group membership more salient and increases helping behaviour towards teammates.
When groups face external threats, members band together more strongly. During natural disasters, entire communities often unite to help each other, regardless of previous divisions.
Groups with longer histories and stronger traditions create more powerful shared identities. Military units with proud histories show exceptional loyalty and helping behaviour between members.
During Hurricane Katrina in 2005, researchers observed how shared identity influenced helping behaviour. People were more likely to help others who shared visible group memberships - whether based on neighbourhood, ethnicity, or even shared experiences of the disaster. However, the overwhelming nature of the crisis also created a broader shared identity of "disaster survivors" that led to remarkable acts of cross-group helping.
Like all psychological theories, Social Identity Theory has both strengths and limitations when explaining prosocial behaviour.
Understanding Social Identity Theory has important implications for promoting helping behaviour in society. By recognising how shared identity works, we can design interventions that increase prosocial behaviour.
Schools can promote helping behaviour by emphasising shared school identity whilst reducing divisions between different groups. House systems, school uniforms and whole-school events all strengthen shared identity and increase mutual support between students.
Social media platforms have created new forms of shared identity that influence helping behaviour. People are more likely to share fundraising appeals, offer support and provide help to others who share their online group memberships - whether based on interests, location, or experiences. The #MeToo movement and various charity campaigns demonstrate how digital shared identities can mobilise massive helping behaviour.