When I wrote this,
I was reminded of a rather different but clearly related argument that I have
seen the Oxford philosopher (but also economist) John Broome make,[1]
although its fullest exploration is probably by Duncan Foley (pdf)[2].
The Stern report
clearly suggests that incurring the costs of mitigating climate change today will
raise the utility of future generations by more than it reduces ours.[3]
However the current generation appears unwilling to incur these costs.[4]
Let us call the ‘status quo’ the situation where nothing much is done to
prevent climate change, and so future generations suffer as a result.
Broome and Foley suggest that a Pareto improvement is
possible compared to the status quo. (A Pareto improvement is
a change where some people are better off, but no one is worse off.) This would
involve taking measures today to mitigate climate change, but getting future
generations to pay for it. How can this trick be pulled off? Following the
logic of the arguments I discussed here
and here
- that government debt involves a transfer between generations - we could pay
for climate change mitigation by issuing government debt, which would be
redeemed by future generations. Reducing CO2 emissions would not cost us
anything, because the money to pay for it would come from selling government
debt to the young. The cost would fall on future generations, who would have to
pay the higher taxes to either service the extra debt or pay it off. The Stern report
suggests future generations would prefer this outcome to the status quo,
because they would be prepared to pay to reduce climate change. It is therefore
a Pareto improvement compared to the status quo. Let’s call this the ‘debt
solution’.[5]
Now there is one immediate and powerful objection to the
debt solution, which is that future generations have to pay for something that this
generation is doing. It violates the polluter pays principle. This makes the
debt solution unfair or unjust. It would be fairer if the current generation
incurs the cost of mitigating climate change, just as it is right for a
company that pollutes a river to pay to clear up the pollution. Let us call
this the ‘just solution’.
The Stern review recommends that we move from the status quo
to the just solution. Unfortunately so far most governments, individually or
collectively, seem unwilling to do this. In these circumstances should we
instead at least start by implementing the debt solution, and then work on
achieving the just solution? Broome suggests “we should not encumber the
process of controlling climate change with the quite different matter of
transferring resources to future people.” That is a controversial suggestion:
many will feel that giving governments that option will reduce the chances of
achieving the just solution. But perhaps this is an example of where the best is the enemy of
the good.
[1]
Broome’s paper is mainly about how we value the hopefully small chance of total
catastrophe, but the argument discussed in this post is made early on in that paper.
[2] Foley,
D. 2007. The Economic Fundamentals of Global Warming. Working paper
07-12-044. Santa Fe, New Mexico: Santa Fe Institute.
[3]
Stern argued that it was ethically wrong to value the utility of future generations less than our own. He values their consumption less, because they will be
better off and so require more consumption to achieve a certain level of
utility. Stern’s report was controversial among many economists because they
prefer to follow the supposed ‘revealed preference’ of the current generation to discount the utility of future generations.
[4] The
qualifier ‘appears’ is important here. My own, relatively uninformed, view of
the politics is that policy in this area is guided by particular vested
interests, rather than the collective view of the current generation. If it was
the case that the current generation was simply unwilling to make a present
sacrifice for future benefit, why is so much money spent on trying to discredit
the evidence about climate change?
[5] Government
debt probably crowds out productive capital to some extent, but this could be
offset if the money spent today involves increasing capital, in the form of
renewable energy generation for example.