Central banking has much in common with chess and fencing. What others think you will do – and to which they pre-emptively react – may matter more than what you yourself actually do in the pursuit of victory. Winning strategies involve feints, signals and the art of calmly manoeuvring opponents to where you want them. Some times the ability to force another’s hand is far more effective than making your own move.

Such thoughts may have been on the minds of the world’s two most important central banks’ governing committees this week. Strictly speaking, the Federal Reserve and the European Central Bank did nothing. But their respective leaders, Ben Bernanke and Mario Draghi, showed how doing nothing is far from being inactive.

Messrs Bernanke and Mr Draghi of course face different predicaments. The US economy, while hardly in top shape, is at least plodding ahead, while the eurozone is wobbling on the edge of a cliff. Both men disappointed investors hoping for more aggressive monetary action. Rather than detonating additional monetary powder, the ECB used its monthly press conference to show that it actually has some powder left, while the Fed’s statement was designed to signal that its powder is still dry.