A smartphone app pinged over 2,000 adults at random moments: what are you doing, what are you thinking about, how happy are you? Their minds were elsewhere 47% of the time, whatever the activity. And people were less happy when their thoughts drifted, even toward pleasant topics. In the authors' words, a wandering mind is an unhappy mind.
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.