In 1977, students watched a video of a lecturer with a foreign accent, acting either warm or cold. When he was friendly, they rated his looks, mannerisms and even his accent as more appealing; when cold, the same traits annoyed them. Asked about it, they denied his warmth had any influence. One good trait spills over onto all the others: the halo effect.
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.