The mixed results from experiments with negative interest rate policy in Europe and Japan have led many to conclude that the idea is ill begotten and should be abandoned. To do so would be a serious mistake.

欧洲和日本试行负利率政策产生了好坏参半的结果，这让许多人断定，负利率的想法考虑不周，应该予以放弃。这将是个巨大的错误。

The negative rate policies that are in place certainly have significant limits and it is not clear how much more can be done in the short term. However, policy could be made far more effective in the long run, once a host of institutional constraints are dealt with. The thorniest problem is avoiding a run into zero-interest cash if interest rates become too negative but even this is far from an insurmountable obstacle, given time.

正在推行的负利率政策当然有着巨大的局限性，而且也不清楚短期还能有多大效果。然而，一旦一系列制度约束解除，这项政策长期而言可能有效得多。最棘手的问题是，如果利率进入较大的负值区间，如何避免发生挤提零利率现金的情况，但假以时日，即便该问题也绝非是难以克服的障碍。

In what could turn out to be a protracted era of low “normal” interest rates, the benefits of clearing the way for effective negative rate policy are potentially significant. If central banks had been able to adopt such policies at the height of the financial crisis, for example, it is likely this would have helped stem the fall in employment, output and asset prices.

我们可能正处于一个低利率成为长期“常态”的时代，为有效负利率政策扫清道路具有潜在的巨大益处。例如，如果各国央行能够在金融危机最严重时期出台此类政策，可能就阻止了就业、产出和资产价格的下跌。

True, Janet Yellen, Federal Reserve chair, has argued that the US central bank should not need to rely on negative interest rates to fight the next deep recession. Unconventional monetary policy tools such as quantitative easing and forward guidance should be enough, she believes, if applied widely.

的确，美联储(Fed)主席珍妮特•耶伦(Janet Yellen)辩称，美联储应该不需要依赖负利率来抗击下一场深度衰退。她相信，如果广泛应用的话，量化宽松和前瞻性指引等非常规货币政策就足够了。

One hopes she is right, given there will probably not be time to lay the foundations for effective negative rate policy before the next recession hits. Unfortunately, based on the academic literature and the experience of the past seven years, there is little reason to believe that is the case.

鉴于在下一场衰退来临之前很可能没有时间为有效负利率政策奠定基础，人们会希望她说的是正确的。遗憾的是，从学术文献和过去7年的经验来看，几乎没有理由认为情况的确如此。

Some people argue that negative interest rates are unnatural and unprecedented. This is certainly an emotive topic but we should at least get the facts straight. Negative rates are not unprecedented in any meaningful sense. Before paper currency, monarchs routinely debased money, for example by introducing coins with a lower silver content and using these to repay debts.

一些人声称，负利率是非自然的，而且史无前例。这当然是一个情绪化的话题，但我们至少应该搞清事实。从真正意义上来说，负利率并非史无前例。在纸质货币之前，君主们定期贬值货币，例如推出含有较低银含量的硬币，并用这些货币偿还债务。

The problem of the zero lower bound — the idea that interest rates could not go lower — only really emerged with paper currency, but then governments simply turned to the printing press to debase currency in real terms through inflation. To say that real interest rates caused by inflation are unfortunate but negative nominal rates are unnatural is to promulgate financial illiteracy.

零利率下限——利率不可能低于零的观点——只是随着纸币的出现才出现的，但接着政府开始通过印钞催生通胀来让货币贬值（实际价值）。说实际利率是通胀导致的固然令人遗憾，但说名义负利率非自然是忽悠那些不懂金融知识的人。

The case for negative rate policy becomes all the stronger when one looks at other proposals for stimulating the economy when the zero lower bound constraint is binding. Of course, there is fiscal policy (and everyone agrees on the desirability of debt-financed infrastructure spending).

在零利率下限的约束下，看看能够刺激经济的其他方法，你会发现更有理由推行负利率政策了。当然政府还可以推出财政政策（所有人都同意举债建设基础设施是可取的）。

Beyond that, there is a swath of policies economists might ordinarily consider highly counterproductive but which can sometimes make sense when monetary policy is unable to generate inflation. These include calls for greater protectionism because it raises prices; backpedalling on structural reform because greater efficiency lowers prices, and an outsize role for the government in private credit markets.

除此以外，一系列政策可能被经济学家认为效果完全适得其反，但在货币政策无法产生通胀的时候，这些政策有时也是具有意义的。它们包括呼吁加强保护主义，因为这会提升价格；让结构性改革倒退，因为效率提升会降低价格；以及让政府过度干预私人信贷市场。

But surely protectionism and negative structural reform are potentially far more dangerous than effective negative interest rate policy, were the latter possible? Clear-headed macroeconomic policymaking is hard enough in normal times. It is far more difficult when the zero lower bound clouds the horizon.

但保护主义和结构性改革倒退的潜在风险肯定要比有效负利率政策大得多——假如负利率政策有可能实施。明智的宏观经济政策制定在正常时期就够困难的了。当零利率下限逼近的时候就更加困难。

The steps that need to be taken are clear enough, particularly phasing out the large denomination notes that would be at the centre of any run into cash. This ought to be done anyway as a measure to reduce crime and tax evasion.

需要采取的举措已经非常明显，尤其是废除大额钞票——如果发生挤提现金情况，大额钞票将是挤提的核心。无论如何都应该废除大额钞票，因为这有助于减少犯罪和逃税。

Whenever the next financial crisis comes, central banks should not have to be asking themselves again why they did not think more about the zero lower bound beforehand. The time to get ready is now.

无论下一场金融危机何时来临，央行都不应再次自问，为何它们没有事先更多地考虑零利率下限。现在就应该做准备。