The Johari Window was invented by Joseph Luft and Harrington Ingham in the 1950s as a model for mapping personality awareness. By describing yourself from a fixed list of adjectives, then asking your friends and colleagues to describe you from the same list, a grid of overlap and difference can be built up.

...play was a sign of the “mind breaking down the determinism of the cosmos”

If you feel you are being watched, you change your behavior.
Big Data is supercharging this effect.

...humor occurs when and only when three conditions are satisfied: (1) a situation is a violation, (2) the situation is benign, and (3) both perceptions occur simultaneously. For example, play fighting and tickling, which produce laughter in humans (and other primates), are benign violations because they are physically threatening but harmless attacks.