To be happy, the ancient Greeks thought they needed to be rich, or powerful, or beautiful. And most people still make the same assumptions.
However, according to the psychologist Mihaly Csikszentmihalyi, what we need is 'flow': a state in which we are fully immersed in a task, and have complete focus. Flow is linked to high performance, particularly in athletes, and also to feelings of contentment and calm.
Csikszentmihalyi's theory has spawned other workplace jargon nuggets, including 'on the ball', 'in the zone' and 'in the groove'. The idea is that, rather than seeking out happiness in shopping malls or by chilling out in front of the TV, we should create it by losing ourselves in a productive activity.
But is flow possible to achieve in the modern workplace? Being a manager in a local authority is not exactly a Zen-like experience.
Recommended strategies include: setting clear goals, having a sense of control and finding an activity which is rewarding. Thus it is easier for Lewis Hamilton or Cristiano Ronaldo to experience flow than it is for someone running a housing department.
It seems likely that retail therapy and evenings spent sprawled in front of EastEnders will be with us for some time to come.