Tag: known unknowns

Many UK coal mines closed in the 1970s and 80s. Coal extraction was too expensive in the UK to compete with cheap imported coal and many consumers were switching away from coal to cleaner fuels. Today many shale oil producers in the USA are finding that extraction has become unprofitable with oil prices having fallen by some 50% since mid-2014 (see A crude indicator of the economy (Part 2) and The price of oil in 2015 and beyond). So is it a bad idea to invest in fossil fuel production? Could such assets become unusable – what is known as ‘stranded assets‘?

In a speech on 3 March 2015, Confronting the challenges of tomorrow’s world, delivered at an insurance conference, Paul Fisher, Deputy Governor of the Bank of England, warned that a switch to both renewable sources of energy and actions to save energy could hit investors in fossil fuel companies.

‘One live risk right now is of insurers investing in assets that could be left ‘stranded’ by policy changes which limit the use of fossil fuels. As the world increasingly limits carbon emissions, and moves to alternative energy sources, investments in fossil fuels and related technologies – a growing financial market in recent decades – may take a huge hit. There are already a few specific examples of this having happened.

… As the world increasingly limits carbon emissions, and moves to alternative energy sources, investments in fossil fuels and related technologies – a growing financial market in recent decades – may take a huge hit. There are already a few specific examples of this having happened.’

Much of the known reserves of fossil fuels could not be used if climate change targets are to be met. And investment in the search for new reserves would be of little value unless they were very cheap to extract. But will climate change targets be met? That is hard to predict and depends on international political agreements and implementation, combined with technological developments in fields such as clean-burn technologies, carbon capture and renewable energy. The scale of these developments is uncertain. As Paul Fisher said in his speech:

‘Tomorrow’s world inevitably brings change. Some changes can be forecast, or guessed by extrapolating from what we know today. But there are, inevitably, the unknown unknowns which will help shape the future. … As an ex-forecaster I can tell you confidently that the only thing we can be certain of is that there will be changes that no one will predict.’

The following articles look at the speech and at the financial risks of fossil fuel investment. The Guardian article also provides links to some useful resources.


Bank of England warns of huge financial risk from fossil fuel investments The Guardian, Damian Carrington (3/3/15)
PRA warns insurers on fossil fuel assets Insurance Asset Risk (3/3/15)
Energy trends changing investment dynamics UPI, Daniel J. Graeber (3/3/15)

Confronting the challenges of tomorrow’s world Bank of England, Paul Fisher (3/3/15)


  1. What factors are taken into account by investors in fossil fuel assets?
  2. Why might a power station become a ‘stranded asset’?
  3. How is game theory relevant in understanding the process of climate change negotiations and the outcomes of such negotiations?
  4. What social functions are filled by insurance?
  5. Why does climate change impact on insurers on both sides of their balance sheets?
  6. What is the Prudential Regulation Authority (PRA)? What is its purpose?
  7. Explain what is meant by ‘unknown unknowns’. How do they differ from ‘known unknowns’?
  8. How do the arguments in the article and the speech relate to the controversy about investing in fracking in the UK?
  9. Explain and comment on the statement by World Bank President, Jim Yong Kim, that sooner rather than later, financial regulators must address the systemic risk associated with carbon-intensive activities in their economies.

Economic journalists, commentators and politicians have been examining the possible economic effects of a Yes vote in the Scottish independence referendum on 18 September. For an economist, there are two main categories of difficulty in examining the consequences. The first is the positive question of what precisely will be the consequences. The second is the normative question of whether the likely effects will be desirable or undesirable and how much so.

The first question is largely one of ‘known unknowns’. This rather strange term was used in 2002 by Donald Rumsfeld, US Secretary of Defense, in the context of intelligence about Iraq. The problem is a general one about forecasting the future. We may know the types of thing that are likely happen, but the magnitude of the outcome cannot be precisely known because there are so many unknowable things that can influence it.

Here are some known issues of Scottish independence, but with unknown consequences (at least in precisely quantifiable terms). The list is certainly not exhaustive and you could probably add more questions yourself to the list.

Will independence result in lower or higher economic growth in the short and long term?
Will there be a currency union, with Scotland and the rest of the UK sharing the pound and a central bank? Or will Scotland merely use the pound outside a currency union? Would it prefer to have its own currency or join the euro over the longer term?
What will happen to the sterling exchange rate with the dollar, the euro and various other countries?
How will businesses react? Will independence encourage greater inward investment in Scotland or will there be a net capital outflow? And either way, what will be the magnitude of the effect?
How will assets, such as oil, be shared between Scotland and the rest of the UK? And how will national debt be apportioned?
How big will the transition costs be of moving to an independent Scotland?
How will independence impact on Scottish trade (a) with countries outside the UK and (b) with the rest of the UK?
What will happen about Scotland’s membership of the EU? Will other EU countries, such as Spain (because of its concerns about independence movements in Catalonia and the Basque country), attempt to block Scotland remaining in or rejoining the EU?
What will happen to tax rates in Scotland, with the new Scottish government free to set its own tax rates?
What will be the consequences for Scottish pensions and the Scottish pensions industry?
What will happen to the distribution of income in Scotland? How might Scottish governments behave in terms of income redistribution and what will be its consequences on output and growth?

Of course, just because the effects cannot be known with certainty, attempts are constantly being made to quantify the outcomes in the light of the best information available at the time. These are refined as circumstances change and newer data become available.

But forecasts also depend on the assumptions made about the post-referendum decisions of politicians in Scotland, the rest of the UK and in major trading partner countries. It also depends on assumptions about the reactions of businesses. Not surprisingly, both sides of the debate make assumptions favourable to their own case.

Then there is the second category of question. Even if you could quantify the effects, just how desirable would they be? The issue here is one of the weightings given to the various costs and benefits. How would you weight distributional consequences, given that some people will gain or lose more than others? What social discount rate would you apply to future costs and benefits?

Then there are the normative and largely unquantifiable costs and benefits. How would you assess the desirability of political consequences, such as greater independence in decision-making or the break-up of a union dating back over 300 years? But these questions about nationhood are crucial issues for many of the voters.


Scottish Independence would have Broad Impact on UK Economy NBC News, Catherine Boyle (9/9/14)
Scottish independence: the economic implications The Guardian, Angela Monaghan (7/9/14)
Scottish vote: Experts warn of potential economic impact BBC News, Matthew Wall (9/9/14)
The economics of Scottish independence: A messy divorce The Economist (21/2/14)
Dispute over economic impact of Scottish independence Financial Times, Mure Dickie, Jonathan Guthrie and John Aglionby (28/5/14)
10 economic benefits for a wealthier independent Scotland Michael Gray (6/3/14)
Scottish independence, UK dependency New Economics Foundation (NEF), James Meadway (4/9/14)
Scottish Jobs and the World Economy Scottish Economy Watch, Brian Ashcroft (25/8/14)
Scottish yes vote: what happens to the pound in your pocket? Channel 4 News (9/9/14)
What price Scottish independence? BBC News, Robert Peston (12/9/14)
What price Scottish independence? BBC News, Robert Peston (7/9/14)
Economists can’t tell Scots how to vote BBC News, Robert Peston (16/9/14)

Books and Reports
The Economic Consequences of Scottish Independence Scottish Economic Society and Helmut Schmidt Universität, David Bell, David Eiser and Klaus B Beckmann (eds) (August 2014)
The potential implications of independence for businesses in Scotland Oxford Economics, Weir (April 2014)


  1. What is a currency union? What implications would there be for Scotland being in a currency union with the rest of the UK?
  2. If you could measure the effects of independence over the next ten years, would you treat £1m of benefits or costs occurring in ten years’ time the same as £1m of benefits and costs occurring next year? Explain.
  3. Is it inevitable that events occurring in the future will at best be known unknowns?
  4. If you make a statement that something will occur in the future and you turn out to be wrong, was your statement a positive one or a normative one?
  5. What would be the likely effects of Scottish independence on the current account of the balance of payments (a) for Scotland; (b) for the rest if the UK?
  6. How does inequality in Scotland compare with that in the rest of the UK and in other countries? Why might Scottish independence lead to a reduction in inequality? (See the chapter on inequality in the book above edited by David Bell, David Eiser and Klaus B Beckmann.)
  7. One of the problems in assessing the arguments for a Yes vote is uncertainty over what would happen if there was a majority voting No. What might happen in terms of further devolution in the case of a No vote?
  8. Why is there uncertainty over the amount of national debt that would exist in Scotland if it became independent?