This column is a lead commentary in the VoxEU Debate "What's the use of economics? "
The simple question that was raised during a recent conference organised by Diane Coyle  at the Bank of England was to what extent has - or should - the teaching of economics be modified in the light of the current economic crisis? The simple answer is that the economics profession is unlikely to change. Why would economists be willing to give up much of their human capital, painstakingly nurtured for over two centuries? For macroeconomists in particular, the reaction has been to suggest that modifications of existing models to take account of ‘frictions’ or ‘imperfections’ will be enough to account for the current evolution of the world economy. The idea is that once students have understood the basics, they can be introduced to these modifications.
A turning point in economics
However, other economists such as myself feel that we have finally reached the turning point in economics where we have to radically change the way we conceive of and model the economy. The crisis is an opportune occasion to carefully investigate new approaches. Paul Seabright hit the nail on the head; economists tend to inaccurately portray their work as a steady and relentless improvement of their models whereas, actually, economists tend to chase an empirical reality that is changing just as fast as their modelling. I would go further; rather than making steady progress towards explaining economic phenomena professional economists have been locked into a narrow vision of the economy. We constantly make more and more sophisticated models within that vision until, as Bob Solow put it, “the uninitiated peasant is left wondering what planet he or she is on” (Solow 2006).
In this column, I will briefly outline some of the problems the discipline of economics faces; problems that have been shown up in stark relief during the current crisis. Then I will come back to what we should try to teach students of economics.
Entrenched views on theory and reality
The typical attitude of economists is epitomised by Mario Draghi, President of the European Central Bank. Regarding the Eurozone crisis, he said:
“The first thing that came to mind was something that people said many years ago and then stopped saying it: The euro is like a bumblebee. This is a mystery of nature because it shouldn’t fly but instead it does. So the euro was a bumblebee that flew very well for several years. And now – and I think people ask ‘how come?’ – probably there was something in the atmosphere, in the air, that made the bumblebee fly. Now something must have changed in the air, and we know what after the financial crisis. The bumblebee would have to graduate to a real bee. And that’s what it’s doing” (Draghi 2012)
Illustration by Rick Billings
What Draghi is saying is that, according to our economic models, the Eurozone should not have flown. Entomologists (those who study insects) of old with more simple models came to the conclusion that bumble bees should not be able to fly. Their reaction was to later rethink their models in light of irrefutable evidence. Yet, the economist’s instinct is to attempt to modify reality in order to fit a model that has been built on longstanding theory. Unfortunately, that very theory is itself based on shaky foundations.
Economic theory can mislead
Every student in economics is faced with the model of the isolated optimising individual who makes his choices within the constraints imposed by the market. Somehow, the axioms of rationality imposed on this individual are not very convincing, particularly to first time students. But the student is told that the aim of the exercise is to show that there is an equilibrium, there can be prices that will clear all markets simultaneously. And, furthermore, the student is taught that such an equilibrium has desirable welfare properties. Importantly, the student is told that since the 1970s it has been known that whilst such a system of equilibrium prices may exist, we cannot show that the economy would ever reach an equilibrium nor that such an equilibrium is unique.
The student then moves on to macroeconomics and is told that the aggregate economy or market behaves just like the average individual she has just studied. She is not told that these general models in fact poorly reflect reality. For the macroeconomist, this is a boon since he can now analyse the aggregate allocations in an economy as though they were the result of the rational choices made by one individual. The student may find this even more difficult to swallow when she is aware that peoples’ preferences, choices and forecasts are often influenced by those of the other participants in the economy. Students take a long time to accept the idea that the economy’s choices can be assimilated to those of one individual.
A troubling choice for macroeconomists
Macroeconomists are faced with a stark choice: either move away from the idea that we can pursue our macroeconomic analysis whilst only making assumptions about isolated individuals, ignoring interaction; or avoid all the fundamental problems by assuming that the economy is always in equilibrium, forgetting about how it ever got there.
Exogenous shocks? Or a self-organising system?
Macroeconomists therefore worry about something that seems, to the uninformed outsider, paradoxical. How does the economy experience fluctuations or cycles whilst remaining in equilibrium? The basic macroeconomic idea is, of course, that the economy is in a steady state and that it is hit from time to time by exogenous shocks. Yet, this is entirely at variance with the idea that economists may be dealing with a system which self organises, experiencing sudden and large changes from time to time.
There are two reasons as to why the latter explanation is better than the former. First, it is very difficult to find significant events that we can point to in order to explain major turning points in the evolution of economies. Second, the idea that the economy is sailing on an equilibrium path but is from time to time buffeted by unexpected storms just does not pass what Bob Solow has called the ‘smell test’. To quote Willem Buiter (2009),
“Those of us who worry about endogenous uncertainty arising from the interactions of boundedly rational market participants cannot but scratch our heads at the insistence of the mainline models that all uncertainty is exogenous and additive”
Some teaching suggestions
New thinking is imperative:
- We should spend more time insisting on the importance of coordination as the main problem of modern economies rather than efficiency. Our insistence on the latter has diverted attention from the former.
- We should cease to insist on the idea that the aggregation of the choices and actions of individuals who directly interact with each other can be captured by the idea of the aggregate acting as only one of these many individuals. The gap between micro- and macrobehaviour is worrying.
- We should recognise that some of the characteristics of aggregates are caused by aggregation itself. The continuous reaction of the aggregate may be the result of individuals making simple, binary discontinuous choices. For many phenomena, it is much more realistic to think of individuals as having thresholds - which cause them to react - rather than reacting in a smooth, gradual fashion to changes in their environment. Cournot had this idea, it is a pity that we have lost sight of it. Indeed, the aggregate itself may also have thresholds which cause it to react. When enough individuals make a particular choice, the whole of society may then move. When the number of individuals is smaller, there is no such movement. One has only to think of the results of voting.
- All students should be obliged to collect their own data about some economic phenomenon at least once in their career. They will then get a feeling for the importance of institutions and of the interaction between agents and its consequences. Perhaps, best of all, this will restore their enthusiasm for economics!
Some use for traditional theory
Does this mean that we should cease to teach ‘standard’ economic theory to our students? Surely not. If we did so, these students would not be able to follow the current economic debates. As Max Planck has said, “Physics is not about discovering the natural laws that govern the universe, it is what physicists do”. For the moment, standard economics is what economists do. But we owe it to our students to point out difficulties with the structure and assumptions of our theory. Although we are still far from a paradigm shift, in the longer run the paradigm will inevitably change. We would all do well to remember that current economic thought will one day be taught as history of economic thought.
Buiter, W (2009), “The unfortunate uselessness of most ‘state of the art’ academic monetary economics ”, Financial Times online, 3 March.
Coyle, D (2012) “