Whenever you move, your brain, especially the cerebellum, predicts the sensations that movement will cause and turns them down. Your own fingers simply can't surprise you. Researchers proved it with a robot: when they added a split-second delay between a person's hand movement and the stroke on their palm, the touch started to tickle again.
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.