All the schools had the same aim: to achieve a way of living known in the original Greek as eudaimonia, often translated as “happiness,” “joy,” or “human flourishing.” This meant living well in every sense: thriving, relishing life, being a good person. They also agreed that the best path to eudaimonia was ataraxia, which might be rendered as “imperturbability” or “freedom from anxiety.” Ataraxia means equilibrium: the art of maintaining an even keel, so that you neither exult when things go well nor plunge into despair when they go awry.

