In 2006, sociologists built a website where 14,341 people listened to and downloaded 48 songs by unknown bands. Some saw download counts, split across eight parallel “worlds”; others saw nothing. When popularity was visible, success became more unequal and less predictable: the same song could be a hit in one world and ignored in another. The best songs rarely flopped and the worst rarely won, but anything else could happen.
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.