Psychology
The Bystander Effect: Social Inhibition of Helping in Emergencies
Quick fact
In a famous series of experiments, when participants thought they were the only person who could hear someone having an epileptic seizure, 85% helped—but when they believed there were four other bystanders, only 31% helped.
Why this is interesting
You're walking down a busy street and see a person collapse. You look around—dozens of people see it too, yet no one moves. Why don't you help? The answer lies in a puzzling social force: the more people around, the less likely anyone will step in.