The Bystander Effect. Why nobody helps, and how to break it.

In a crowd, everyone assumes someone else will act. The more people present, the less likely any one of them is to help. This has been measured in experiments since the 1960s. The fix is specific: point at one person and give them a task. "You, in the blue shirt, call an ambulance."

• Naming a specific person breaks the diffusion. Responsibility that belongs to everyone belongs to no one.
• If you need help in a crowd, do not shout "someone help." Pick one person and speak to them directly.