The natural world is an incredible wonder that inspires us all, but despite our love of wildlife and wild places, there is no doubt that it is facing catastrophic decline, here and abroad. George Monbiot (The UK government wants to put a price on nature – but that will destroy it, 15 May) suggests that in efforts to save the natural world there are grave dangers in putting a “price on nature”.

Yet one reason we are failing to do what is necessary is because nature is still seen as “nice to have”, rather than essential in sustaining our health, wealth and security. Many companies, economists and governments regard environmental destruction as a regrettable but inevitable consequence of economic growth – the “price of progress”. If we don’t change this mindset, then there will be little prospect for the revolution in ideas that is needed to avoid a mass extinction event and disastrous climatic changes.

Nature underpins our economy, society and very existence. Talking about the economic contribution of the natural world does not lead to a price on nature, but rather it helps explain its hidden values. Talking about how we rely on healthy nature does not require conservationists to abandon their love of nature, their spiritual connections with it or the moral case for action. It does, however, add one more crucial argument for the kind of changes we need to secure.

Tony Juniper

Director of advocacy and campaigns, WWF

• George Monbiot says trying to account for the value of nature will inevitably lead to its commodification and destruction. But our global economic system already places economic values on the natural world – and has done so for centuries. The problem is that the price placed on ecosystems and biodiversity is effectively zero. Our economies see these things as worthless because we have failed to measure, understand and account for the true value of nature’s riches. Markets remain largely blind to these benefits, and thus we consume them to the point of destruction.

Monbiot is incorrect when he says that “price represents an expectation of payment, in accordance with market rates”. In fact, price represents the attribution of economic value. Natural capital does not prepare nature for sale; it calls attention to the worth of what is lost. We have argued that all human prosperity rests on nature, and Monbiot is correct to point out that many natural resources are irreplaceable. Unfortunately, until we place a proper value on natural capital, the global economic system will continue to merrily saw away at the branch we’re all sitting on. Decades of well-intentioned conservation have done little; a new approach is required. Properly valuing the huge, irreplaceable natural contributions that we all depend on is a good place to start.

Cameron Hepburn Professor of environmental economics, Smith School, University of Oxford, and director of economics of sustainability, INET, Oxford Martin School, Alex Teytelboym Associate professor, Department of Economics, University of Oxford, Francois Cohen Senior research officer, INET Oxford Martin, Kirk Hamilton Visiting professor, Department of Geography and Environment, LSE

Green Economy Coalition

• I would certainly agree that calculating the value of nature only in economic terms is sterile and meaningless. However, in dealing with a government that demonstrates its only values are driven by economic considerations, the Natural Capital Committee has been a consistent supporter of environmental causes and gained the support of many environmental groups such as the Woodland Trust and Green Alliance. No doubt some conservatives would want the committee to take a narrow approach to their terms of reference, but they have clearly taken as wide an approach as possible and support many of the causes that Monbiot holds dear. Using economic and financial arguments for environmental causes, as Mr Monbiot often does himself, should not be seen as a threat, but as a source of vital support.

Ira Unell

Nottinghamshire

• George Monbiot rightly cites Michael Sandel’s excellent book What Money Can’t Buy. I have found Sandel’s analysis to be enormously helpful in my work with city leaders. After the financial crash of 2008 many advocated new laws to rein in greed and force bankers to act more responsibly. These steps are still needed. But, as Monbiot affirms, Sandel identified an even bigger challenge: “The most fateful change that unfolded during the past three decades was not an increase in greed. It was the expansion of markets, and of market values, into spheres of life where they don’t belong.” Making a stand against market values is now more important than ever.

Robin Hambleton

Emeritus professor of city leadership, University of the West of England

• Jason W Moore in Capitalism in the Web of Life argues that appropriating “cheap nature” (raw materials, energy, food, labour, including women’s reproductive labour) is the fundamental condition allowing capital to extract its surplus from the production process. Forcing up the price of “nature” is therefore one of the best strategies for hastening the demise of capitalism, an outcome devoutly to be wished for all on the green left.

True, putting up a “This is not for sale” notice (fencing off rewilded land, leaving oil in the ground) is one of the best tactics for pushing up prices. But we still need to eat, to reproduce, and to produce the means of subsistence, and sometimes an exorbitant price (for example, on pollinating insects, on childcare or on clean water) might work better. So maybe the best approach is purely tactical: keep both critiques, incompatible as they are, in mind, and apply whichever is more likely in particular circumstances to achieve the desirable outcome.

This approach best reflects the point that actually there is no natural world separate from the sphere of human endeavour; each is the creation of the other, and both market values and intrinsic values are human constructs for us to manage as best we can.

Richard Middleton

Castle Douglas, Dumfries and Galloway

• I think George Monbiot may have missed the point. What if we valued nature at replacement cost? What if we charged palm oil producers the cost of restoring the environment so that numbers of orangutans returned to former levels? What if we valued nature generally at what it would cost to regenerate the passenger pigeon, the dodo, or countless other species of animals, birds, fish and plants – and the ecology on which they would depend? In practical terms, since we have no idea how to do that, the cost and therefore the value would be infinite. Let economists put that in their models and see what happens.

Robert Dimmick

Reading, Berkshire

• If the government and conservation organisations continue to insist that monetary values be ascribed to woodland and wildlife, the risk is that a development scheme that can create value £1 in excess of the supposed worth of your local woods will be economically compelling and will inevitably go ahead, replacing “natural capital” with housing capital or retail capital. Perhaps a solution would be to say that many natural “assets” are of infinite value, being unique locally or having an indefinite past and future (if left alone). People could be encouraged to list their local meadows, riverbanks, etc as being infinitely valuable, and then it would be impossible to mount an economic argument that they should be built upon.

Dominic Rayner

Leeds

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