I’m told that the cliché du jour in financial markets involves reference to ‘uncharted territory’. It’s things like the GDP figures which are responsible for that. We’re deep in the land of Rumsfeld’s unknown unknowns. (Why, incidentally, was he so widely mocked for talking about the difference between known and unknown unknowns? It seems to me an immensely useful distinction, not least as a way of describing the difference between what economists call risk, which markets can measure and therefore like, and uncertainty, which they can’t and therefore hate.)

John Lanchester

But it can’t be a useful distinction, John — Donald Rumsfeld made it.