For over a decade I’ve been researching the history of the seven deadly sins. This is the self-help system, devised in the Egyptian desert over 1,600 years ago, that claimed to identify the basic habits of the mind. It turns out that the medieval wisdom applied to these habits – pride, envy, anger, sloth, avarice, gluttony and lust – can be mapped on to the modern world pretty well. Studying pride taught me how to deal with narcissists, for example. But it was the fourth sin, sloth, that really opened my eyes.