All the schools had the same aim: to achieve a way of living known in the original Greek as eudaimonia2, 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.

