Fischhoff and Beyth had students estimate the odds of various outcomes before a major diplomatic trip. Afterwards, they were asked to recall their own forecasts. They remembered assigning higher odds to whatever had actually happened. Hindsight bias quietly edits your past predictions so they match the outcome, which is why everything feels obvious once it's over.
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.