In 1990, Elizabeth Newton asked volunteers to tap the rhythm of well-known songs on a table. Tappers predicted half of listeners would name the tune. In fact, only 3 songs out of 120 were identified, a mere 2.5%. The tapper hears the melody in their head; the listener hears knocking. That's the curse of knowledge: once you know something, you can't imagine not knowing it.
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.