... what we’re talking about here is nothing new, in terms of kind. Nathan Rothschild built a significant chunk of his fortune by using a system of couriers who told him the result of the Battle of Waterloo a full day before anybody else in London knew it. And my own employer, the Reuter news agency, was founded on sending financial information between Brussels and Aachen using carrier pigeons.

What’s new is that billions of pounds can be made by having access to information not a day in advance, or an hour, or even a second, but even just a millisecond or two. Stock exchanges aren’t physical places where human beings bargain with each other any more: they’re racks of computers in places like Mahwah, New Jersey, where the cables are carefully measured to be exactly the same length so that no one has an infinitesimal advantage thanks to the amount of time it takes information to travel an extra few millimeters down a wire.