In the 1950s, Harry Harlow separated infant rhesus monkeys from their mothers and gave them two substitutes: one made of wire with a milk bottle, the other covered in soft cloth but with no milk. The babies spent most of their time clinging to the cloth mother, visiting the wire one only to feed, and ran to the cloth one when frightened. Comfort mattered more than food, a lesson learned through experiments now considered cruel.
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.