“It is quite impossible to unite happiness with a yearning for what we don’t have. Happiness has all that it wants, and resembling the well-fed, there shouldn’t be hunger or thirst.” —EPICTETUS, DISCOURSES, 3.24.17 I’ll be happy when I graduate, we tell ourselves. I’ll be happy when I get this promotion, when this diet pays off, when I have the money that my parents never had. Conditional happiness is what psychologists call this kind of thinking. Like the horizon, you can walk for miles and miles and never reach it. You won’t even get any closer.