What is the right course for monetary policy? The International Monetary Fund seems to answer with forked tongue. Its latest World Economic Outlook urges that monetary policy should stay loose to stimulate growth. Yet its Global Financial Stability Review warns that loose monetary policy risks creating financial instability, which could crimp growth. In fact the best policy is to print money and raise interest rates. That sounds contradictory, but it is not.

The global economy is suffering the hangover from many decades of excessive private-sector credit growth. In 1950 private credit in advanced economies was 50 per cent of gross domestic product; by 2007 it was 170 per cent. After the 2008 crisis, households and companies began trying to pay back what they owed. This depressed consumption and investment, generating large fiscal deficits as tax revenues fell and social expenditure rose. It then seemed essential to balance public sector accounts, which has depressed growth further and made deleveraging harder. Debt owed by the public and private sectors has actually increased as a proportion of GDP, from 170 per cent five years ago to 200 per cent today. Weak demand has led to below-target inflation in all major economies.

Economists agree that this is how we got into the current mess, but they disagree about how to get out of it. Some, such as Paul Krugman and Lawrence Summers, argue for more relaxed fiscal policies. Cutting taxes or increasing public expenditure is the most certain way to stimulate demand. In Milton Friedman’s words it is an injection directly “into the income stream”. But this route out of recession would increase public debt even further. It seems blocked.