Some psychologists take exception with Epicurus’s focus almost exclusively on pain relief. “Happiness is definitely something other than the mere absence of all pain,” sniffs the Journal of Happiness Studies. Before reading Epicurus, I would have agreed. Now I’m not so sure. If I’m honest with myself, I recognize that what I crave most is not fame or wealth but peace of mind, the “pure pleasure of existing.” It’s nearly impossible to describe such a state in terms other than that of absence.