It was to be expected that our present economic traumas would call into question the state of economics. “Why did no one see the crisis coming?”, Queen Elizabeth reportedly asked one practitioner. A seminar at the British Academy tried to answer and the FT has taken up the discussion.

The Queen’s question is understandable, given the subject’s claims on its own behalf. Ever since modern economics started in the 18th century it has presented itself as a predictive discipline, akin to a natural science. Since the future a year ago included the present slump, it is natural that the failure of the economics profession – with a few exceptions – to foresee the coming collapse should have discredited its scientific pretensions. Economics is revealed to have no more clothes than other social science. One cannot imagine the Queen in, say, nine months’ time, asking a leading political scientist: “Why did no one tell me that Labour was going to win the election?” She would understand that this was not a prediction that any political scientist could make with conviction, however much time he had spent studying present and past opinion polls.

Nevertheless, the Queen’s question was wrong, because it accepted at face value the predictive claim of economics – a feature that has distinguished it from all other social sciences. Karl Popper produced a famous argument against the possibility of prediction in human affairs: one cannot anticipate a new invention because, if one could, one would already have invented it. However, this objection can be overcome if one assumes a stable and repetitive universe in which rational actors make efficient use of the information available to them. In this environment, uncertainty disappears to be replaced by calculable risk. Shocks and mistakes may occur but these will cancel each other out, so that, on average, people get what they expect.

An important implication of this view is that shares are always correctly priced. This is the basis of the so-called efficient market hypothesis that has dominated financial economics. It led bankers into blind faith in their mathematical forecasting models. It led governments and regulators to discount the possibility that financial markets could implode. It led to what Alan Greenspan called (after he had stepped down as chairman of the US Federal Reserve) “the underpricing of risk worldwide”.

It has also led to the discrediting of mainstream macroeconomics. The efficient market hypothesis is simply an application of the recently triumphant New Classical school, which preaches that a decentralised market system is always at full employment. In their obsession with getting government out of economic life, Chicago economists claimed that any consistent set of policies will be learnt and anticipated by a population, and will therefore be ineffective. Since people – apparently including the 10 per cent or so unemployed – are already in their preferred position because of their correct anticipations and instantaneous adjustment to change, “stimulus” policies are bound to fail and even make things worse. Recessions, in this view, are “optimal”.

Most of those unversed in New Classical economics assume that John Maynard Keynes exploded these fallacies 70 years ago. Their re-emergence is not just the result of the failure of Keynesian macroeconomic policy to anticipate or deal with “stagflation” in the 1970s. It reflects a persistent bias in economics towards an idealised account of human behaviour; what Joseph Schumpeter called the “Ricardian Vice” of excessive abstraction. It is only by imagining a mechanical world of interacting robots that economics has gained its status as a hard, predictive science. But how much do its mechanical constructions, with their roots in Newtonian physics, tell us about the springs of human behaviour?

One of the most interesting contributions to the FT.com debate was the argument that, after Keynes, economists should have aligned their discipline with other social sciences concerned with human behaviour. Keynes opened the way to political economy; but economists opted for a regressive research programme, disguised by sophisticated mathematics, that set it apart. The present crisis gives us an opportunity to try again.

The reconstruction of economics needs to start with the universities. First, degrees in the subject should be broadly based. They should take as their motto Keynes’s dictum that “economics is a moral and not a natural science”. They should contain not just the standard courses in elementary microeconomics and macroeconomics but economic and political history, the history of economic thought, moral and political philosophy, and sociology. Though some specialisation would be allowed in the final year, the mathematical component in the weighting of the degree should be sharply reduced. This is a return to the tradition of the Oxford Politics, Philosophy and Economics (PPE) degree and Cambridge Moral Sciences.

Beyond this, the postgraduate study of macroeconomics might with advantage be separated from that of microeconomics. Courses in microeconomics should concern themselves, as at present, with the building and testing of models based on a narrow set of assumptions. Their field of applicability lies in those areas where we have reliable views of the future. Macroeconomics, though, is an essential part of the art of government, and should always be taught in conjunction with subjects bearing on this.

The obvious aim of such a reconstruction is to protect macroeconomics from the encroachment of the methods and habits of the mathematician. Only through some such broadening can we hope to provide a proper education for those whose usefulness to society will lie as much in their philosophical and political literacy as in their mathematical efficiency.

How to resolve this crisis in macroeconomics? The field must be revamped fundamentally. Some of its shortcomings are obvious. Before the financial crisis, most macroeconomists were blinded by the idea that efficient markets would take care of themselves. They did not bother to put financial markets and the banking sector into their models. This is a major flaw.

There is a deeper problem, though, that will be more difficult to resolve. This is the underlying paradigm of macroeconomic models. Mainstream models take the view that economic agents are superbly informed and understand the deep complexities of the world. In the jargon, they have “rational expectations”. Not only that. Since they all understand the same “truth”, they all act in the same way. Thus modelling the behaviour of just one agent (the “representative” consumer and the “representative” producer) is all one has to do to fully describe the intricacies of the world. Rarely has such a ludicrous idea been taken so seriously by so many academics.

We need a new science of macroeconomics. A science that starts from the assumption that individuals have severe cognitive limitations; that they do not understand much about the complexities of the world in which they live. This lack of understanding creates biased beliefs and collective movements of euphoria when agents underestimate risk, followed by collective depression in which perceptions of risk are dramatically increased. These collective movements turn uncorrelated risks into highly correlated ones. What Keynes called “animal spirits” are fundamental forces driving macroeconomic fluctuations.

The basic error of modern macroeconomics is the belief that the economy is simply the sum of microeconomic decisions of rational agents. But the economy is more than that. The interactions of these decisions create collective movements that are not visible at the micro level.

It will remain difficult to model these collective movements. There is much resistance. Too many macroeconomists are attached to their models because they want to live in the comfort of what they understand – the behaviour of rational and superbly informed individuals.

To paraphrase Isaac Newton, macroeconomists can calculate the motions of a lonely rational agent but not the madness of the crowds. Yet if macroeconomics wants to become relevant again, its practitioners will have to start calculating this madness. It is going to be difficult, but that is no excuse not to try.

March 2, 2009

Remember the good old days, when we used to talk about the “subprime crisis” — and some even thought that this crisis could be “contained”? Oh, the nostalgia!

Today we know that subprime lending was only a small fraction of the problem. Even bad home loans in general were only part of what went wrong. We’re living in a world of troubled borrowers, ranging from shopping mall developers to European “miracle” economies. And new kinds of debt trouble just keep emerging.

How did this global debt crisis happen? Why is it so widespread? The answer, I’d suggest, can be found in a speech Ben Bernanke, the Federal Reserve chairman, gave four years ago. At the time, Mr. Bernanke was trying to be reassuring. But what he said then nonetheless foreshadowed the bust to come.

The speech, titled “The Global Saving Glut and the U.S. Current Account Deficit,” offered a novel explanation for the rapid rise of the U.S. trade deficit in the early 21st century. The causes, argued Mr. Bernanke, lay not in America but in Asia.

In the mid-1990s, he pointed out, the emerging economies of Asia had been major importers of capital, borrowing abroad to finance their development. But after the Asian financial crisis of 1997-98 (which seemed like a big deal at the time but looks trivial compared with what’s happening now), these countries began protecting themselves by amassing huge war chests of foreign assets, in effect exporting capital to the rest of the world.

The result was a world awash in cheap money, looking for somewhere to go.

Most of that money went to the United States — hence our giant trade deficit, because a trade deficit is the flip side of capital inflows. But as Mr. Bernanke correctly pointed out, money surged into other nations as well. In particular, a number of smaller European economies experienced capital inflows that, while much smaller in dollar terms than the flows into the United States, were much larger compared with the size of their economies.

Still, much of the global saving glut did end up in America. Why?

Mr. Bernanke cited “the depth and sophistication of the country’s financial markets (which, among other things, have allowed households easy access to housing wealth).” Depth, yes. But sophistication? Well, you could say that American bankers, empowered by a quarter-century of deregulatory zeal, led the world in finding sophisticated ways to enrich themselves by hiding risk and fooling investors.

And wide-open, loosely regulated financial systems characterized many of the other recipients of large capital inflows. This may explain the almost eerie correlation between conservative praise two or three years ago and economic disaster today. “Reforms have made Iceland a Nordic tiger,” declared a paper from the Cato Institute. “How Ireland Became the Celtic Tiger” was the title of one Heritage Foundation article; “The Estonian Economic Miracle” was the title of another. All three nations are in deep crisis now.

For a while, the inrush of capital created the illusion of wealth in these countries, just as it did for American homeowners: asset prices were rising, currencies were strong, and everything looked fine. But bubbles always burst sooner or later, and yesterday’s miracle economies have become today’s basket cases, nations whose assets have evaporated but whose debts remain all too real. And these debts are an especially heavy burden because most of the loans were denominated in other countries’ currencies.

Nor is the damage confined to the original borrowers. In America, the housing bubble mainly took place along the coasts, but when the bubble burst, demand for manufactured goods, especially cars, collapsed — and that has taken a terrible toll on the industrial heartland. Similarly, Europe’s bubbles were mainly around the continent’s periphery, yet industrial production in Germany — which never had a financial bubble but is Europe’s manufacturing core — is falling rapidly, thanks to a plunge in exports.

If you want to know where the global crisis came from, then, think of it this way: we’re looking at the revenge of the glut.

And the saving glut is still out there. In fact, it’s bigger than ever, now that suddenly impoverished consumers have rediscovered the virtues of thrift and the worldwide property boom, which provided an outlet for all those excess savings, has turned into a worldwide bust.

One way to look at the international situation right now is that we’re suffering from a global paradox of thrift: around the world, desired saving exceeds the amount businesses are willing to invest. And the result is a global slump that leaves everyone worse off.

So that’s how we got into this mess. And we’re still looking for the way out.