Monetary policy is an art, not a science; it is the art of taking one’s best guess. And, as the 2008-2009 crisis demonstrated, merely cleaning up after the bubbles burst is very costly and inefficient.
诚然，央行行长无法确切地知道资产价格何时达到了不可持续的高水平。但他们也无法确切地知道通货膨胀何时会突飞猛进。货币政策是一种艺术而不是一种科学；它是“猜准”的艺术。2008—2009年危机表明，仅仅在泡沫破裂后收拾局面事倍功半。