A GROWING movement wants to radically change how we live. The people behind it say it will make us healthier, happier and more productive. It will put a massive dent in carbon dioxide emissions and ease the pressure on nature. And it will make countries richer and more equal. But are we really ready for a four-day week?

In the UK, at least, the idea is gaining ground. Some trade unions have come out in support , the Labour party and the Scottish National …