THESE words circulate, often in whispers, whenever people feel alienated from the world—when Death, Famine, Hunger and Plague come, the Four Horses of the Apocalypse.

The virus now spreading from place to place is entirely different in scale to contagions of times past, but once again ‘Who Knows’ resurfaces. Let us take a look: Marchionne di Coppo Stefani’s notes on the terrible plague that attacked Florence in 1348