The deliberative model has not been tried and tested in anger for the full gamut of societal decisions. As put, that is true. Yet there is at least one domain of public policy where this model has been tried and tested (both literally and metaphorically) for a wide range of societal decisions over many centuries: the judicial system. Many judicial systems draw on both expert (judges) and non-expert (juries) opinion, like the Athenians. Non-experts are drawn randomly from the population, as in Athens. There is a clear process for deliberation among participants, as in the boule. This system is the nerve-centre of decision-making on a defined set of issues, as in Ancient Greece. The English judicial system has already lasted for almost 1,000 years, more than twice as long as the Greek Empire. The Next Revolution  Against this backdrop, what concrete steps might central banks take to build an improved infrastructure for engagement with the general public? Can it build on others’ experience in engaging wider society, in ways which improve the public’s and policymakers’ understanding of the economy? Let me offer some suggestions, which are motivated by recent initiatives at the Bank of England aimed at doing just that. 19  All speeches are available online at www.bankofengland.co.uk/speeches  19  (a)  Minding Your Language  Historically, the language of central banks has often been pitched at a level which has made it difficult for most non-experts to understand. This has contributed to the public’s understanding and trust deficits.
The sample period is relatively short so our conclusions need to be cautious. And forecast accuracy is not the same as policy acumen. Nonetheless, Chart 3 suggests that, in a complex forecasting task, there is little to choose between experts and 37  non-experts. Tetlock’s second key point, which qualifies his first, is that not everyone can be a super-forecaster. A randomly-chosen panel of non-experts cannot by itself be expected to outperform the experts. Chart 3 demonstrates that. Super-forecasting is not simply a law of large numbers. Tetlock shows that non-expert super-forecasters have particular characteristics, including inquisitiveness and independence of mind. Only those with these characteristics consistently outperform the experts. We do not have a clean test of this hypothesis for our inflation forecasts. But just imagine the Bank had been able to identify in advance one “super-forecaster” among the pool of outside forecasters. How much would that have improved its forecasts over the sample period? The gap in two year-ahead forecast errors between the MPC and the best external forecaster in the panel of outside forecasters is around ¼ percentage point. 20/20 hindsight is a wonderful thing, but this gives some measure of the scope for forecast improvement. 38  If we take Tetlock’s points together, they suggest that there is real value in seeking the views of non-experts to help inform difficult decisions. But there are limits to these benefits. It is unrealistic to expect everyone to become a super-forecaster.