Leaving aside the cases of individual traders low-balling Libor for bottles of Bollinger, the act of entire banks submitting false Libor rates opens up the Pandora’s box that is 'game theory' – and shows how Barclays played the wrong hand.

Game theory is a mathematical concept developed by Hungarian-American polymath John von Neumann and German-born economist Oskar Morgenstern in the 1940s, which looks at the way in which people react in certain situations.