Later experiments showed that in an emergency, the greater the number of witnesses, the less it was that any of them would intervene. Each bystander assumed someone else would offer . This collective public to help became known as ‘the bystander effect’. On the contrary, when an faked street accidents for just one bystander, he or she offered help 70% of the time.

An American TV programme called What Would You Do? tests the bystander effect using hidden cameras. Members of the public witness ‘crimes’ such as stealing in a crowded store, and their are filmed. Recent episodes have included not only crimes but moral dilemmas, such as children abusing a homeless person on a busy street. We all like to think of ourselves as people – but could you really beat the bystander effect?