When work becomes an obsession, compulsive behaviours develop that can be harmful and even death-producing. As in hoarding money, gambling, sex or any other process addiction, the act itself (working) loses its intrinsic meaning. Although the line between simple overwork and an unhealthy addiction to work is tenuous, it is fairly easy to tell when one has crossed it. The workaholic uses work to avoid dealing with inner and interpersonal life.
During the Middle Ages in England, peasants could work just 150 days a year. Until relatively recently, work was seen as painful toil, and best avoided. But something changed in the 16th century – we started to think that work was morally good.