In 1978, a family of Russian ‘Old Believers’ living in a supposedly uninhabited part of the Siberian taiga were discovered by a team of geologists. They had fled Stalinist persecution, and for half a century had lived in isolation in a ‘low, soot-blackened log kennel’ with a floor made of potato peelings and crushed nutshells, one tiny window, a fire, a single rushlight, and one item of furniture — an axe-hewn table.