And the third is tight restrictions on debt and leverage, especially in the housing market, in order to prevent a credit-fueled price bubble from forming. To these solutions, Keynes would have added a fourth, one known to us today as the “Greenspan put” – using monetary policy to validate the asset prices reached at the height of the bubble.
如今，我们认识到信贷渠道受阻可以导致经济下行。对此也有三个经常提出的应对方案。一是扩张性的财政政策，在私人投资不振的情况下政府把相关责任承担起来。二是提高通胀目标，给与中央银行更多的空间去应对金融冲击。三是对负债和杠杆严加管控，尤其是住宅市场，防止形成由信贷推动的价格泡沫。在这三个之外，凯恩斯会加上第四条，我们如今称之为“格林斯潘对策”——利用货币政策去将泡沫最高峰时的资产价格合理化。