…There is a well-known joke about economic methodology. Two friends are walking along when one spots a €50 note on the floor. “Look!” he says, “Let’s pick up the money.” His friend, an economist, replies: “No, don’t bother. If it were really there, somebody would have picked it up already.” The joke of course is about the lack of realism in the assumptions economists conventionally make in order to analyse the real world….
In practice, the version of this assumption used in applied analysis is rarely as strong. In practice, it is more like: given the limited information available to them, and the various transaction costs they face in taking certain courses of action, and given that the future is very uncertain, we’ll assume people act broadly in their self-interest, however they would define that. I would strongly defend the use of this contingent version of the standard assumption as it’s a powerful analytical tool…. Modern institutional economics, which is a thriving area of research, is founded on the use of the rationality assumption as a tool of analysis. If people do not seem to be making the rational choice, then looking at the difference between what would happen if they did so and the reality is instructive….
I would defend using the assumption of rational choice as long as one realises that it is not a description of reality. But there is one area where for 30 years economists – and others – have been making that mistake. That is, unfortunately, of course, in the financial markets. Practitioners and policy makers acted as if the strong form of the Efficient Markets Hypothesis held true – in other words that prices instantly reflect all relevant information about the future – even though this evidently defies reality. What’s more, a political philosophy valuing limited government leapt on what was taken as proof that markets left to themselves deliver better economic outcomes. This was translated as the deregulation of markets, especially financial markets, and became entwined with the growing importance of the finance sector in the economy globally. So politics fed the trend. The computer and communications technologies fed the trend as well, by making more and more financial transactions possible.
I think an honest conventionally-trained economist has to at least acknowledge that we grew intellectually lazy…. A particular ideological version of economics became the framework for analysing public policy, and very few mainstream economists challenged that. We got on with our work and ignored the importance of the public rhetoric….
A looser version is that a public sphere founded on the world view of narrow, rational choice economic models has over time led people to behave like the selfish, calculating beings assumed in those models. If regulations assume that you are going to behave in a certain way, there must surely be a temptation to live up to the assumption. I don’t know if this theory of economic performativity is true; perhaps the causality runs the other way, and a period of free-market politics especially in the US and UK changed the character of economics? We can’t test these alternatives, but this criticism is worth considering….
The financial and economic crisis [thus] spells a crisis for certain areas of economics, or approaches to economics. Financial economics and macroeconomics are particularly vulnerable. They are the subject areas where the consequences of the standard assumptions have been most damaging, because they are actually least valid. Financial market traders are not remotely like Star Trek’s Mr Spock, making rational calculations unaffected by emotion or by the decisions of other people. Macroeconomics – the study of how millions of individual decisions aggregate into economy-wide measures – is essentially ideological. How macroeconomists answer a question like ‘What will be the effect of cutting the budget deficit on growth next year?’ depends on their political views. This is not remotely a scientific area of the discipline….
I can’t omit here a few other problems with economics as it has been practised… the economics curriculum in universities… gives too much time to macroeconomics, on which as I just argued there is no professional consensus…. They have little sense of economic history…. Students are also not systematically taught new aspects of the subject…. Undergraduates are also taught as if they are all planning to go on to study for a doctorate and become academic economist…. Finally, many of these under-cooked economics graduates go on to work in government…. There are some good reasons for this special status – I’m about to come on to those – but the influence economists have in government needs seasoning with a corresponding degree of humility. One side-effect of the crisis may be to make economists a bit more humble, which would be a good result.
