"Happiness is equal to or greater than your perception of the events of your life minus your expectations of how life should behave. Which means that if you perceive the events as equal to or greater than your expectations, you're happy -- or at least not unhappy.
"But here's the tricky bit: It's not the event that makes us unhappy. It's the way we think about it that does."
- Mo Gawdat, Solve for Happy