[...] (Happiness) is what’s there when you remove the sense that something is missing in your life. We are highly judgmental, survival, and replication machines. We are constantly walking around thinking I need this, I need that, trapped in the web of desires. Happiness is that state when nothing is missing. When nothing is missing, your mind shuts down and your mind stops running into the future or running into the past to regret something or to plan something.
Excerpt from Naval Ravikant on Reading, Happiness, Systems for Decision Making, Habits, Honesty and More by Farnam Street