In 1980, psychologist Peter Thompson cut the eyes and mouth out of a photo of Margaret Thatcher and pasted them back upside down. With the whole picture inverted, the face looks almost normal. Flip it the right way up and it becomes grotesque. The “Thatcher effect” shows that we read upright faces as a whole, through the relations between features. Upside down, that holistic processing breaks down and the oddities slip by.
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.