A 1988 study claimed that holding a pen between your teeth, forcing a smile, made cartoons seem funnier. In 2016, 17 labs reran it with nearly 1,900 participants: no effect. A large international collaboration in 2022 confirmed the pen trick fails, though deliberately mimicking a smile nudged mood up very slightly.
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.