I’ve just been listening to this fascinating Reith Lecture by Mark Carney on the BBC.
https://www.bbc.co.uk/programmes/m000qkms
 
He quite correctly identified the main features of the Climate Crisis and some of the ways many people in the worlds of finance and economics are trying to solve this presenting problem, and even to go further to build a sustainable future beyond just stabilising the climate.
He is to be commended for such a salient and well-constructed series of talks, of which this one was the fourth and final one.
He seems to place a lot of confidence in the ability of market mechanisms, operating alongside government policies and regulatory legislation, to provide the shift in investment required to rebalance human activities and reflect changing citizen values on the planet and sustainability.

In my view, if I can be a "critical reviewer" for a moment, he gave only a partial response to the question by Tanya Steel (WWF) – about 42 minutes into the transmission – regarding the lack of valuations being placed on standing rainforests (as opposed to felled forests for land use change into agriculture).  Although he mentioned Natural Capital, he expressed some concerns about using Natural Capital approaches to put a value on nature.  His main concern, which has been expressed by others (including the famous environmentalist George Monbiot), is that putting a value on nature could make it easier (and more attractive) for businesses or individuals to make profits by exploiting those natural assets, in particular by converting them from capital assets into produced goods (eg cutting down trees to make wood and changing the land from forest use into more profitable agricultural use.

This is a well-worn concern about Natural Capital but it can be addressed.  The key thing to realise is that, in most forests, the fact that they are not valued at all as a standing capital asset makes it much easier for them to be exploited for profit than if they had a standing forest value as a capital asset.  This is because the cost of the raw material is currently essentially zero and no economic damage is recognised when the trees are felled.  Placing a value on the standing forest as a capital asset (Natural Capital) would make it clear that felling the trees in an unsustainable way would be destroying value, by reducing the value of that capital asset without a larger compensating value creation from that activity.  The main solution is to emphasise the necessary change of priority from a “flow” model of the economy (as typified by GDP) to a “stock” model, with managing national and global Balance Sheets being more important for a sustainable future than just managing the annual flows (equivalent to a profit and loss account).  

Stock Flow Consistent (“SFC”) economic modelling has been around for several years, and it was a missed opportunity for Mark Carney not to mention this in his lecture. The SFC approach follows the premise that it is important to manage balance sheets as well as income and expenditure if you want your enterprise to have a long-term future.  If that enterprise is an entire country (or the whole world) then we have for too long focussed almost entirely on the income and expenditure (eg GDP) and neglected the national and global balance sheets (incorporating Natural Capital).  SFC modelling is, in fact, one of the most obvious things to explore as part of current moves to implement Natural Capital in National Balance Sheets (in National Systems of Accounts), and ultimately we should be maintaining and enhancing World Balance Sheets over time, including the whole of the Natural Capital of the Earth, as this is what the continued thriving of our species (and many others) depends on.  For more about this concept, see WorldBalanceSheet.com

Steady State Economics might not be the best answer to current and future sustainability challenges.  It might not even be sufficient as a solution, in its current form, as advocated by CASSE (The Centre for Advancement of Steady State Economics). 
It might, however, be a useful stepping stone to better solutions we can’t yet know about, let alone express in economic terms.  Some of the work of Brian Czech, Director of CASSE, and other authors in “Best of the Daly News” (ie Czech, 2020) is examined further below and in my forthcoming book, due to be published  in 2021.  And SSE might be a whole lot better than the current way economies are managed (or left to markets) in most parts of the world today.
However, it's worth setting some wider context first, which will help to explain why this, and other new forms of economic thinking, are a necessary field of thought and practice to address our current predicament. 
 
The Bottleneck humanity hopes to pass through
 “The Precipice” by Toby Ord (ie Ord, 2020) resonates with my own perspectives on the long-term development of humanity and the risks it currently faces.
Ord points out that humanity is at a critical crossroads, where its power has outstripped its wisdom, resulting in several serious existential risks (including unsustainability of our impacts on nature, rogue AI (Artificial Intelligence), engineered biological agents and conflicts that might, potentially, involve nuclear weapons). 
The finite planetary limits of the biosphere that supports us are like a bottle containing a model ship in the classic “ship in a bottle”.  Our population and civilisation are like the ship.  The human ecological footprint has been growing as we have developed (the ship has been growing in size and complexity inside the bottle).  But we are realising that the finite bounds of the biosphere, and the damage caused by our overshooting sustainable thresholds, is reducing the size of the biosphere and its capacity to support us (the neck of the bottle has been narrowing, as a result of our actions) and the rate of that depletion in biospherical capacity is accelerating. 
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We want humanity to progress further, because our future potential is immense if we can more effectively harness the energy from the sun (the only input from outside the bottle) and if we can access materials from outside the earth system, for example by mining materials on the moon, from asteroids or find even more distant exploitable resources.  After all, the universe outside the bottle is potentially infinite in materials, energy and evolutionary progress for living beings.
Our challenge is to pass through the neck of the bottle, and to pull what we can of the ship, through with us, without destroying the bottle that is humanity’s birthplace. 
It becomes obvious there are two main options for doing this, which are not mutually exclusive. 
Firstly, we can modify our impacts on the natural biosphere, to reduce (and eventually reverse) the rate of degradation of the biosphere’s capacity to support us (slow down, and then reverse, the rate at which the neck of the bottle is shrinking). 
Secondly, we can alter our civilisation and the way it draws resources from the biosphere and uses them, for example adopting circular systems of material and energy flow, such as those advocated in circular economy, or even implementing something along the lines of a steady state economy, a GDP-growth-agnostic economy or something similar (remodel the ship so it will more easily pass through the neck). 
If we can do these things, a bright future awaits and the innumerable future generations of humanity will thank us for our efforts.
If we fail, however, our failure will go down in history as the biggest failure of any known life reaching a state of advanced intelligence and civilisation.
We should use the sense of responsibility this imparts as a spur to action.
The bottleneck analogy is used also, extensively, in White and Hagens (2020) “The Bottlenecks of the 21st Century”.
 

I think Daniel Yergin's "The Commanding Heights" is an excellent and highly relevant book, published in 1998 but still highly relevant today.  I find myself dipping into it again and again, as it tracks the ebb and flow of the balances (and imbalances) in many nations and globally between 'the market' and 'the state' or (occasionally) global governance mechanisms.  Although he seems (mostly) to fall on the side of supporting market approaches, at the end of the book he hints at the possibility of a resurgence of 'the state' and its role as regulator of things like environmental protection and climate change where markets fail or generate damage and harm.  

The following is from page 390: 
“Yet if the market is seen to fail on either of those two grounds - results and restraint - if its benefits are regarded as exclusive rather than as inclusive, if it is seen to nurture the abuse of private power or the specter of raw greed, then surely there will be a backlash - a return to greater state intervention, management, and control.  The state would again step forward to expand its role as protector of the citizenry against the power of private interests, whether exercised through monopoly, wanton behaviour, fraud and deception, or exploitation and direct harm." 
Was Yergin hedging his bets, or expressing some real concerns and fears that markets, insufficiently fettered, would be likely to wreak havoc with the planetary biosphere and climate, throwing us well beyond sustainability thresholds and requiring increasingly drastic national and international government and governance actions?

Tietenberg (2018) provides similar conclusions:
“In summary, the record compiled by our economic and political institutions has been mixed. It seems clear that simple ideological prescriptions such as “leave it to the market” or “let the government handle it” simply do not bear up under a close scrutiny of the record. The relationship between the economic and political sectors has to be one of selective engagement, complemented in some areas by selective disengagement. Each problem has to be treated on a case-by-case basis. As we have seen in our examination of a variety of environmental and natural resource problems, the efficiency and sustainability criteria allow such distinctions to be drawn, and those distinctions can serve as a basis for policy reform …
Our examination of the evidence suggests that the notion that all of the world’s people are automatically benefited by economic growth is naïve. Economic growth has demonstrably benefited some citizens, but that outcome is certainly not inevitable for all people in all settings.”
  
The "commanding heights" of the economy (nationally and globally) continue to be a vital piece of context for the challenge of transitioning (or 'transcending') to sustainability, and our money systems play a key part in that.
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Maintenance and reform of money systems are a legitimate role for the state.
These issues transcend party politics.  Indeed, I think the vision of achieving global sustainability and social justice is often damaged when it becomes co-opted by political movements, as these often result in polarisation of debates, and unnecessary conflicts.