There is a long list
of culprits when it comes to assigning blame for the financial crisis.
At least in this instance, failure has just as many parents as success.
But among the guilty parties, economists played a special role in
contributing to the problem. We are duty bound to be part of the
solution (see Coyle 2012). Our role in the crisis was, in a nutshell,
the result of succumbing to an intellectual virus which took hold of the
body financial from the 1990s onwards.
One strain of this
virus is an old one. Cycles in money and bank credit are familiar from
centuries past. And yet, for perhaps a generation, the symptoms of this
old virus were left untreated. That neglect allowed the infection to
spread from the financial system to the real economy, with near-fatal
consequences for both.
In many ways, this
was an odd disease to have contracted. The symptoms should have been
all too obvious from history. The interplay of bank money and credit
and the wider economy has been pivotal to the mandate of central banks
for centuries. For at least a century, that was recognised in the design
of public policy frameworks. The management of bank money and credit
was a clear public policy prerequisite for maintaining broader
macroeconomic and social stability.
Two developments
– one academic, one policy-related – appear to have been responsible for
this surprising memory loss. The first was the emergence of
micro-founded dynamic stochastic general equilibrium (DGSE) models in
economics. Because these models were built on real-business-cycle
foundations, financial factors (asset prices, money and credit) played
distinctly second fiddle, if they played a role at all.
The second was an
accompaying neglect for aggregate money and credit conditions in the
construction of public policy frameworks. Inflation targeting assumed
primacy as a monetary policy framework, with little role for commercial
banks' balance sheets as either an end or an intermediate objective.
And regulation of financial firms was in many cases taken out of the
hands of central banks and delegated to separate supervisory agencies
with an institution-specific, non-monetary focus.
Coincidentally or
not, what happened next was extraordinary. Commercial banks' balance
sheets grew by the largest amount in human history. For example, having
flatlined for a century, bank assets-to-GDP in the UK rose by an order
of magnitude from 1970 onwards. A similar pattern was found in other
advanced economies.
This balance sheet
explosion was, in one sense, no one’s fault and no one’s responsibility.
Not monetary policy authorities, whose focus was now inflation and
whose models scarcely permitted bank balance sheets a walk-on role. And
not financial regulators, whose focus was on the strength of individual
financial institutions.
Yet this policy
neglect has since shown itself to be far from benign. The lessons of
financial history have been painfully re-taught since 2008. They need
not be forgotten again. This has important implications for the
economics profession and for the teaching of economics. For one, it
underscores the importance of sub-disciplines such as economic and
financial history. As Galbraith said,"There can be few fields of human
endeavour in which history counts for so little as in the world of
finance." Economics can ill afford to re-commit that crime.
Second, it
underlines the importance of reinstating money, credit and banking in
the core curriculum, as well as refocusing on models of the interplay
between economic and financial systems. These are areas that also fell
out of fashion during the pre-crisis boom.
Third, the crisis
showed that institutions really matter, be it commercial banks or
central banks, when making sense of crises, their genesis and aftermath.
They too were conveniently, but irresponsibly, airbrushed out of
workhorse models. They now needed to be repainted back in.
The second strain of
intellectual virus is a new, more virulent one. This has been made
dangerous by increased integration of markets of all types, economic,
but especially financial and social. In a tightly woven financial and
social web, the contagious consequences of a single event can thus bring
the world to its knees. That was the Lehman Brothers story.
These cliff-edge
dynamics in socioeconomic systems are becoming increasingly familiar.
Social dynamics around the Arab Spring in many ways closely resembled
financial system dynamics following the failure of Lehman Brothers four
years ago. Both are complex, adaptive networks. When gripped by fear,
such systems are known to behave in a highly non-linear fashion due to
cascading actions and reactions among agents. These systems exhibit a
robust yet fragile property: swan-like serenity one minute, riot-like
calamity the next.
These dynamics do
not emerge from most mainstream models of the financial system or real
economy. The reason is simple. The majority of these models use the
framework of a single representative agent (or a small number of them).
That effectively neuters the possibility of complex actions and
interactions between agents shaping system dynamics.
The financial system
is an archetypical complex, adaptive socioeconomic system – and has
become more so over time. In the early years of this century, financial
chains lengthened dramatically, system-wide maturity mismatches widened
alarmingly and intrafinancial system claims ballooned exponentially.
The system became, in consequence, a hostage to its weakest link. When
that broke, so too did the system as a whole. Communications networks
and social media then propagated fear globally.
Conventional models,
based on the representative agent and with expectations mimicking
fundamentals, had no hope of capturing these system dynamics. They are
fundamentally ill-suited to capturing today’s networked world, in which
social media shape expectations, shape behaviour and thus shape
outcomes.
This calls for an
intellectual reinvestment in models of heterogeneous, interacting
agents, an investment likely to be every bit as great as the one that
economists have made in DGSE models over the past 20 years. Agent-based
modelling is one, but only one, such avenue. The construction and
simulation of highly non-linear dynamics in systems of multiple
equilibria represents unfamiliar territory for most economists. But
this is not a journey into the unknown. Sociologists, physicists,
ecologists, epidemiologists and anthropologists have for many years
sought to understand just such systems. Following their footsteps will
require a sense of academic adventure sadly absent in the pre-crisis
period.
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