In March 1964, Kitty Genovese was murdered in New York. The New York Times reported that 38 neighbors watched the attack and did nothing, a story that launched research on the bystander effect. But only a few neighbors saw part of the attack; most had only heard cries in the night, and one neighbor went down to hold her in her arms. In 2016, the paper admitted it had grossly exaggerated.
Remembering is not replaying a recording — it is rebuilding. Each time you recall a memory, it becomes temporarily malleable and can be altered before being stored again. That is why two people can sincerely remember the same event… differently.
In 2003, Johnson and Goldstein compared European countries. Where you must tick a box to become a donor, consent rates ranged from 4% to 28%. Where you're a donor by default unless you opt out, they topped 85%. People aren't more generous on one side; most simply stick with whatever option was chosen for them.