The best books on Economics and the Environment

Before we look at the books you’re recommending, could you explain the relationship between economics and the environment? One view that I sometimes hear from people who care passionately about the environment is that economics is about GDP growth and that degrowth is the solution—but that’s not where you’re coming from. What’s your perspective on what economics does right, and what it does wrong?

There’s what economics is supposed to do, and there’s what economists actually do, and there’s a distinction between the two. Economics is really just about the allocation of scarce resources. It’s about allocating and making choices where there’s scarcity. The natural environment is, obviously, a scarce resource. It’s the critical building block of an economy and therefore why wouldn’t you be interested in how best to allocate this scarce resource?

So economics and the environment shouldn’t be separate subjects. But they are, because what many economists do is focus on this allocation as if it were a GDP problem. The public representation of economics is often, ‘How can we maximise GDP? How can we have more and more economic growth as defined by GDP?’ That, I think, is very short-sighted and quite a lot of economists now realise that.

But there are deeper problems, too. I’m interested in the longer-term, intergenerational effects. I’m interested in how we make sure that people in the future—citizens, not just consumers—have the ability to choose how to live their lives. Part of what’s required for that is not GDP flow and utility and trying to make people happy; it’s about making sure that these core infrastructure assets—of which natural capital is the most important—are properly maintained and passed on to future generations.

That is all economics, but it’s not economics as most people conceive of it. That’s why quite a lot of my work is critical of the conventional way in which economists address these questions.

From the perspective of a member of the public who’s trying to understand how they should behave, how should I be thinking about the challenges? Is it about who I vote for? Is it about what I do with my trash?

It’s about what you and I do because we are the ultimate polluters. Companies don’t go around thinking at the board table, ‘How can I do some more pollution today?’ Activists go and chain themselves to the railings or doors of oil companies. They think, ‘If only these nasty oil companies would do the right thing and close down fossil fuel production!’

But 80 percent of the world’s energy is fossil fuels. It’s 70-something percent in the UK. You and I buy that stuff. Companies wouldn’t produce the oil unless you used it. They wouldn’t produce the gas, whether it’s in the North Sea or elsewhere, unless you used it. We are the ultimate polluters. It’s us humans that make the world as it is.

We can try to organise in two ways. One is about what you and I choose to do. I choose not to fly. I’ve got loads of hypocritical behaviours that I engage in, but occasionally I try and do the right thing. We should all do our bit. That’s really important.

But it’s also about being aware that, as humans, we’re almost insatiable when it comes to consumption—and we don’t want to pay the costs. That’s why we have governments and laws that set frameworks, within which markets (and you and I) engage in exchange, production, and so on. We want a framework that curtails our insatiable expenditures and that makes us live within our means, save enough for our pensions, repair the potholes in the road and look after the rivers by stopping pollution.

It’s both of those things that we need to do. We can stop a lot of this.

In your recent book, Legacy, you argue that the solutions aren’t rocket science, but it’s going to be expensive. It would be the kiss of death for any politician to mention higher taxes at the next election. Is it more a political challenge than an economic one?

The popular rhetoric now is, ‘It’s all those ghastly politicians! They’re terrible. They’re making the wrong choices. They’re not saving the planet, etc.’ No. Politicians are the ones we elect. They’re very good at working out (for example) that anyone of my generation is thinking about their pension and will vote for the triple lock. We are innately protective of our own self-interest, and we struggle to see the collective one.

What we try to avoid is electing politicians who are going to tell us how it is. We want to be told that renewables are ten times cheaper than fossil fuels. To which my response is, ‘If only!’ If only it were true they were ten times cheaper, we could stand outside Parliament with a placard saying, ‘End renewable subsidies today!’ You don’t need a massive subsidy to get Apple to produce the iPhone 16 (or whatever it is) because it’s economical to do so.

It’s not true that these things are cheap. They’re expensive. What I think is required is some politicians who tell us the truth. At the moment, we haven’t a hope in hell of achieving 1.5 degrees as a maximum warming.

If you’re in the frontline in Ukraine, and you’re President Zelensky, you’re not going to stand up and say, ‘You know what, we’ve got these Russians coming towards us, but it’s not going to cost you anything and you don’t have to change your lifestyle, you don’t have to contribute.’ No, you say, ‘It’s an immediate threat. I’m going to tell you there’s some blood, sweat and tears involved in this.’

“We are the ultimate polluters. It’s us humans that make the world as it is”

I’ve been writing about climate change for fifteen years or more. I’ve always said that if you want to take a wholly fossil-fuel economy and turn it into a low-carbon economy in the space of 25 years, it’s not going to be cheap.

It’s like being in 1938 and saying, ‘Oh my goodness. We’ve got a peacetime economy. We’ve got to be on a war footing to fight the Battle of Britain in 1941. How do we convert between the two?’ We didn’t say, ‘You know what? We’ve got a Second World War coming up. Let’s lower taxes now!’ In fact, taxes on that occasion, believe it or not, went up to 98 per cent. The government took the surplus and invested in what was required.

Now, I’m not proposing that. What I am saying is: tell people the truth. Tell people we’re living beyond our sustainable means. Tell them the world where we live within our sustainable means might be quite painful to get to, but it’s a hell of a lot more painful if we don’t get there. You don’t have an option. You can either hit the brick wall and be made sustainable, or you can opt now to move towards that world. It’s going to be really challenging so don’t tell people it’s all apple pie and custard—it’s not.

The general public gets told this story and then discovers it actually costs you a lot of money to have a heat pump. It’s really quite expensive to buy and run an electric car. There isn’t enough charging publicly available. My bill is going up by another 30/40/50 pounds to pay for the new transmission lines. The public then says, ‘Whoa! I said I was in favour of tackling climate change, but I was told it was free! And suddenly I find it’s not true.’ That’s the crucial point.

But didn’t World War II ultimately lead to quite a lot of economic growth? Didn’t that investment, in some sense, pay off in the long term?

In the short term it certainly didn’t. After the war, in 1945, much of the housing stock was damaged, power stations and the transport system were in a terrible state—we had all the effects of war. We carried on with forced savings in order to extract surpluses from consumers and divert them via the government into investment in these core infrastructures.

From 1945 through to the mid-70s, GDP growth (though it’s not a very good measure) was about 3 percent per year. We were catching up, we were rebuilding. Increased demand for electricity was 7 percent per year. That’s probably what we’re going to have again. We built all the power stations out of customers’ bills. Nobody borrowed to do that.

Borrowing is the new illusion. You can have investment, but don’t worry, it doesn’t cost you anything, because it’s borrowing. What you really mean is, ‘We would like the investment, and to have the benefits from it, but our kids can pay for it.’ Just to remind you, the top rate of tax in 1979 was still 83 percent. Again, people don’t want to vote for that, and you can see why. Because they’ve been told they can have an ever-lower tax economy. Good luck with that!

If you want a lower tax economy, you can have it, but you’ll also have the potholes in the roads, the state of the schools, the houses, etc. Like climate change, none of this stuff is a free lunch, but we’re told it’s a free lunch because we want to vote for a free lunch. We, the voters, want to be told that we don’t have to pay.

Let’s turn to the books you’re recommending. How did you set about choosing them? First up is Predicting Our Climate Future by scientist David Stainforth.

The books I recommended are in two or three blocks. The first two are both about science and technology, in their broadest sense. Predicting Our Climate Future is a wonderful book because it doesn’t try to make it all very simple, but it does make it understandable. Stainforth addresses lots of issues in the book, but a central issue is, ‘This is fundamentally uncertain. If you want certainty—if you want to know exactly how much climate change is going to be, what’s going to happen to the weather, whether it’s going to be wetter next winter—you can’t have that.’

We are condemned to a world of uncertainty but, as he says very clearly in the book, this is a one-shot bet. It’s not as if you can say, ‘Let’s try this out and see if it works, and in 2050 we’ll try something else.’ Nor can we say, ‘Well, we’re not sure how much climate change is going to be, so let’s wait and see.’ You have to make a stab. He makes observations about the uncertainty, about the fact that the world we’re going into is not going to be like the world in the past. It’s not just about extrapolation and induction going into the future.

He spells all this out, but then demonstrates very clearly that these are reasons why we should get on with the problem and address it, rather than pretending it’s all some predictable, planned outcome that we can just work out, scientists will tick the box, and off we go. I think it’s very sobering for those who are certain about everything, and it’s also very clear about the reasons why, in this world of uncertainty, we should act.

What does the book by Mustafa Suleyman, The Coming Wave, bring to the picture?

Like Stainforth’s book, The Coming Wave is about the future. It reminds us that we’re very uncertain about how this will be. That’s the human condition, that’s what makes human life interesting, that we don’t know whether tomorrow is going to be like today, and we’re not sure exactly how it’s going to work. We always have to act in a world of uncertainty.

What The Coming Wave does is tell you that if you think the future is uncertain, you ain’t seen nothing yet. The book describes what AI and synthetic biology are bringing. We actually live on the cusp—or are already in the middle of—a much greater revolution in technology and technical change than humans have ever seen.  It’s very bracing and challenging.

The book argues that synthetic biology and genetics mean that even what it is to be human is not actually going to be that clear. We can now manipulate the stuff of life. Add AI to this, and just think it through. I don’t recall if The Coming Wave deals with this, but Elon Musk’s company has now got to the point of inserting a chip in the brain and controlling that from a computer. This is just a slight insight into what’s potentially coming. If you add quantum computing on top of AI, our capacity to handle data, to understand stuff—it’s an enormous opportunity. It’s not clear how it’s going to work out.

The added piece that comes from The Coming Wave is the recognition that almost all scientific progress is two-edged. The analogy is the case of nuclear, where it may be possible to have energy one day that’s too cheap to measure. Fusion offers that possibility going forward. But it also has the capacity to destroy the world in a couple of minutes. When Putin speculates about battlefield nuclear weapons, I’m reminded that, in the language of The Coming Wave, we don’t have a way of containing these technologies. We just don’t know how to do it. It’s true that we haven’t had a nuclear war, or a nuclear engagement since Hiroshima, but my view is that’s probably luck.

So, you have these challenges going forward, and it’s a two-edged sword. They need to be addressed. This is the world in which we have to think through our environmental problems. It’s not the world that most environmentalists think about, in which it’s all about existing technologies.

That’s why I like this book, even though it’s got a lot of hype in it (as you would expect). Stainforth’s book is very carefully referenced and grounded. We need both. We need an imagination of the future of the world and, also, a recognition of the uncertainty we confront.

Mustafa Suleyman was at DeepMind, wasn’t he—he’s someone who knows what he’s talking about, I guess.

He’s been at the forefront of this. He was at DeepMind, but he’s now taken up a new role as the CEO of Microsoft AI. He’s an entrepreneur and he writes like an entrepreneur. Sometimes that’s really infuriating, and sometimes it’s just bracingly good. We academics tend to turn our noses up at people who write like that; I think we should take them a bit more seriously.

Let’s turn to the Milton Friedman biography, Milton Friedman: The Last Conservative, by historian Jennifer Burns. How does this fit in?

The next two books are about capitalism. One of them is this excellent biography of Milton Friedman. The book reveals that Friedman is an old-fashioned, classical liberal, not a conservative. But that’s just a slight gripe with the subtitle.

The book is reminding us what the case for capitalism is. Everyone’s anti-capitalist nowadays, but when you stand back and look at the issue, what exactly is it they’re against? As we go into this world where people are much more critical of capitalism, it’s important to recognise the arguments.

In the book, Jennifer Burns illustrates that Milton Friedman was much more than a brilliant academic, which I think everyone would agree he was: he got a Nobel Prize for economics. He was highly controversial, and many of his views, particularly on monetarism, are subject to debate. But he was much more a policy person, thinking about the architecture of policy. Of course he had a big role in the framework of Reagan and Thatcher.

As a general rule, I think people should read things about people they disagree with. I think it’s fatal to go around and say (not that I am), ‘Oh, I’m a Keynesian, so I’ll read lots of books by good Keynesians.’ No! When I was an undergraduate a long time ago, like most students I thought Marx was brilliant, and I made myself read Hayek.

The book also frames the debate about what firms and corporations are for in capitalism. Friedman’s view was that company directors and businesses should pursue profit, full stop. That’s often quoted in the text of ESG (environmental, social and governance) corporate purpose literature—it starts by saying Friedman is wrong.

A view shared by the author of your next book, Capitalism and Crises: How to Fix Them.

Yes, it’s by Colin Mayer, who is a friend and colleague over a long period (I actually worked with him in business, too). His book is a challenge to that view that Friedman had about corporations.

Friedman had lots of ideas: he wanted universal benefits; he wanted negative income taxes. But he wanted the state to do the public goods stuff. He didn’t want us to do what Colin Mayer would like us to do, which is to get the boards of companies to act beyond narrow profit maximisation to choose wider objectives, and to set a purpose for the business that meets social objectives as well as just private greed. I’m paraphrasing Colin badly—but that tension between those two books is very interesting.

My take is that, although I would not think of myself as in any way sympathetic with the bulk of monetarism as Friedman advanced it, I would question whether or not I really want to live in a society where people in the C-suite (the top executives—the CEO etc) decide what the public interest is. I’ve done a lot of work in advising businesses and in the private sector, and I’m not a critic of people who are executives of business. They achieve a great deal. But I’m very sceptical about them deciding what’s good for my community. Normally, the sorts of businesses that do this are businesses that have market power. They’ve got money they can extract from their consumers to spend in certain ways.

Colin and I have sparred on these issues for a long time, and the book is brilliant. You must read it.

“It’s not true that these things are cheap. They’re expensive”

The sophisticated argument of Mayer’s book, from my point of view, is that what companies should do is pursue enlightened self-interest. In other words, pursuing a purpose. Rather than saying, ‘How do I make short-term profits?’ it may well be that producing the best vacuum cleaner (for example) is the most profitable route. James Dyson made a lot of money because he was obsessed by making something that was special.

Mayer’s book tells you what really serious long-term profit maximisation would look like. If you’re being charitable, that’s also what Friedman said: ‘You’re set in a role; you should pursue profit maximising.’ Reading those two books together, you’ll find that there’s more common ground than many of the more popular writers on this subject would suggest.

Colin Mayer’s approach to the purpose of business is very smart, very clever and very well argued. The book’s extremely well written. It’s not the radical manifesto that many of the anti-capitalists would advance. Colin is not arguing is for abolishing capitalism. He’s not an anti-capitalist.

He’s writing a book showing how capitalism could be much more sophisticated, and I think that’s right in the context of private equity and the short-termism that’s gone on which, in my view, he doesn’t attack enough. The financial capitalism we’ve had bears much more criticism. I think Friedman would have probably been quite critical, too.

What’s the solution? Does it involve legislation?

It would be nice if the world was run by altruists, if you and I behaved more environmentally responsibly, if all the directors of companies had studied PPE at Oxford and thought more about wider social requirements. That would be a bonus.

But I want to design a world for average human beings—people with flaws, people who aren’t always the nicest people on the planet. I want to make sure that the rules under which competition operates—the rules of capitalism—are properly set. For me, it’s about more politics, more democracy, more framing the context of what we can do. Part of that’s saving us from our own personal insatiable desire to consume, part of it is protecting us from behaving in ways that are selfish to the degree that they’re self-destructive.

We live in a society. We’re not abstract individuals—in the way that, actually, Friedman thought we were, and Thatcher, too. We’re part of a society. Society sets the rules. Some of them are formal laws, some of them are cultural, some of them are about institutions. That’s where I would like to see more of the effort going. Indeed, that’s where I’d like to see the effort in not just capitalism and social organisation generally, but in respect to the environment specifically.

That’s why I like carbon taxes, for example, that make you pay for the pollution you cause.

One other thing about Colin’s book: he talks about Adam Smith and how we shouldn’t only be reading The Wealth of Nations, we should also be reading The Theory of Moral Sentiments. One person we interviewed on Five Books a few years ago was Karl Rove, George W Bush’s policy adviser. Rove said the same thing. Interesting that they both express those views.

Yes, though for me the Adam Smith issue between The Wealth of Nations and The Theory of Moral Sentiments is more fundamental than either of them probably indicate.

Most economists are utilitarians. They believe that we should maximise utility and that all there is to life is utility.

In The Theory of Moral Sentiments, that leans in the direction of ‘positive freedom.’ The way I put it in my Legacy book, what we should be doing is empowering future citizens to choose how to live their lives, by making sure that they inherit a set of assets at least as good as we did, including the natural environment.

I didn’t try to make my children happy. I’m keen that they are happy, but what I did was try to make sure they had the wherewithal to choose how to live their lives. That’s how we should think about the next generation. It’s crazy to think, ‘Let’s make sure they have lots of utility!’ It’s a bit like Brave New World.

What I want to do is make sure they’ve got a decent education, a health system that supports them, a natural environment that is good around them. We want to make sure the rivers are clean, there’s access to broadband, to power, to sewerage and water systems that work. Then, they can choose how to live their lives. That’s positive freedom.

That is Amartya Sen, who is not a utilitarian. I betray my origins here: he was my doctoral supervisor. It’s the Sen view of the world—positive freedom—and the notion of the idea of justice within that frame, coined in the context of citizens, not consumers, which drives me to focus on the assets that are required and not the utility.

Most of Adam Smith goes in the direction of utilitarianism. He just likes to throw in some moral constraints on utilitarianism. I want to throw utilitarianism out the door and start with citizens and their entitlements.

And that’s all laid out in your book, Legacy?

It’s crucial that Legacy isn’t just about GDP, why that’s wrong and how to do the accounts. It starts from, ‘What do we mean by making sure the next generation has good options? What are our duties to the next generation?’

What I do in that frame is say, ‘Let’s treat the next generation as the next set of citizens and look at their access to society, their capacity to perform, the capacity for the economy to function. That’s about these assets, which include the climate and ecosystems, but not just that. It’s about the basic infrastructure.

Our duty to them is to ensure we fix the potholes in the road, do the maintenance, fix the school roofs, fix the climate, fix Thames Water and the state of the rivers. Those are capital maintenance requirements. What’s wrong with what’s going on now is all that capital maintenance is treated as an investment. It isn’t. It’s a day-to-day obligation on us, out of our current consumption, to fix those holes.

Because when you treat it as an investment, then both political parties say, ‘Oh, you can just borrow to invest.’ What you’re really saying is, ‘Okay, we will fix the potholes eventually, when all other options have been exhausted. We’ll finally get rid of them. But, by the way, you future people can pay for it, because we’ll borrow from you. We’re not actually going to put money aside now to deal with it.’ That’s the difference.

Are you talking about literal potholes or metaphorical ones?

Both. Because a citizen having access to things at the most basic level, for quite a lot of people, especially in urban areas, means it has to be possible to cycle without killing yourself. Outside my house, the roads of West Oxfordshire touch on the edge of Gloucestershire (where they do resurface roads). You wouldn’t go on a bicycle round where I am—you’d get killed! You’d come off and have an accident. There are just gaping potholes.

It’s a metaphor for the state of the school roofs, the hospitals, the railway lines, the bridges that are failing along the Thames, for the state of the sewers that are putting the rubbish in the rivers. But it’s also literal. You need transport. It’s a basic access right that citizens need.

Every generation’s job is to hand those over, as good stewards, to the next generation. That means we have to pay for it. It’s not investment—it’s capital maintenance. That’s what I would engrave on the front page of every manifesto for a political party for the coming election: ‘It’s the capital maintenance, stupid!’ As opposed to: ‘It’s the economy, stupid!’ That would be a good starter.

Your last book recommendation is Stuck Monkey: The Deadly Planetary Cost of the Things We Love by James Hamilton-Paterson. Great title. I read the first chapter, about how we really should not have pets.

It’s a fantastic book. It’s not an academic book, but it is written by a really good and long-time writer in these areas. You want everyone involved in economics and climate change to just be pulled up short every now and then and ask, ‘What’s going on here?’

The monkeys, of course, are us. At the beginning of the book, James Hamilton-Paterson describes this tribe of hunters who hunt monkeys and eat them. The way they do it is they put a banana in a jar with a narrow entrance, and the monkeys can’t resist the banana. They put their hand in, and even though they could get their hand out, they don’t because they’re just addicted to it.

What he is essentially saying is, ‘Look, before you get too carried away with various other explanations, remember there’s something fundamental about us humans and what we’re doing. That’s why our planet is going the way it’s going.’ Essentially, it’s about the fact that deep in our human nature is an insatiable desire to consume. We just can’t resist it.

He goes through pets; through flying and transport; through fast fashion. He points out, in each of these areas, how destructive these activities are, how much damage they’re doing. It brings home, at a personal level, what we humans are up to.

Several years ago, I went past a demonstration outside an oil company, and there were school kids there on a climate strike. It was wonderful. These were bright kids, really caring passionately, prepared to get out on the street and engage. But I wondered how many of them were flying off on holiday, by themselves or with their family, to a beach somewhere, and doing all the consumption that’s involved in flying. I read somewhere that the traveling footprint of environmentalists compared to everybody else is roughly the same.

It’s this disconnect between what you’re doing and what you’re protesting about—blaming these ghastly companies.

“Deep in our human nature is an insatiable desire to consume”

In the book, Hamilton-Paterson does fall, at the beginning, into the trap of saying it’s these giant corporations. It isn’t! The book actually tells you it isn’t them—it’s us that’s doing the damage. It really brings it home to you. It ultimately poses the question that nobody really wants to address (and he doesn’t really answer it), which is: ‘Are we doomed? Is the reason we’re destroying our planet because human nature plus technology is going to do this, that we’re just programmed to do this, that evolution has made us like this? Or are we capable of constructing a framework to constrain and confine our natural predilection to consume more and more and more?’

I think that’s an open question. I think all environmentalists have to think quite hard about setting a frame that constrains the pollution that you and I and everybody else does in a socially just way—rather than simply think it’s someone else’s fault.

Hamilton-Paterson’s book is so well written. It’s confronting everyone’s prejudices. He deliberately starts off with pets because people like pets. The book is in your face, in a very easy-going way. I thought it was a brilliant book. And it’s sobering. That’s the word I would use.

Finally, in terms of your own books—for anybody who is new to your work—could you say a bit about them?

I never intended to write anything other than academic books, but a publisher came to see me in about 2010 or 2011 and said, ‘I’ve read all your stuff. This is the book you should write. It’s all about climate change and why we’re getting it wrong.’I was completely bowled over by this but thought, ‘OK, I’ll rise to the challenge!’

I wrote a book called The Carbon Crunch, which was designed around the question: ‘Why, after (at that stage) twenty years of effort, have we achieved so little?’ Indeed, a lot of what I’ve subsequently written is still about, ‘Why have we achieved so little?’

I got distracted in 2012, when I was asked by David Cameron to chair the Natural Capital Committee. I’m very unpolitical. If a politician asks me to do something and they’re elected, I’ll do my best. We had a remit in the Natural Capital Committee to develop natural capital thinking and work out how to impose that. We worked on the 25 Year Environment Plan, the Environment Act, the Agriculture Act (with Michael Gove) and that whole programme.

While I was doing it, I thought, ‘I quite liked writing The Carbon Crunch!’ The first part of the Natural Capital Committee was about what natural capital means, so I wrote a book—which is deliberately designed to be accessible—called Natural Capital. I stand by it all, still, now.

As we went on, we got to the application and the development of the 25 Year Environment Plan. It’s about the only thing I’ve ever done that’s now in law. I wrote a book called Green and Prosperous Land to explain how we could do it, what agriculture would look like, what our cities would look like, etc—again, for a popular audience.

After that I thought, ‘I’m finished. I’ve written everything I want to write.’

But then I read the introduction to a climate change committee report by John Gummer, its chairman. It was their advice to government about whether to adopt a 100 per cent net zero target. He wrote that when we get to the net zero, we’ll no longer be causing climate change. I was so angry because this is so obviously not true.

The way we measure net zero is on terrestrial carbon emissions, so if we just close down some more industries, it will look better. If you deindustrialise, the home emissions will be lower—but you’ll import all the stuff instead. ‘Today, we’re closing Port Talbot and Grangemouth refineries. Great! Our emissions go down. What heroes we are!’ Actually, climate change will be worse because we’re going to import the steel from China and the petrochemicals from elsewhere. I was angry, so I wrote my book about net zero, and what net zero should actually mean in terms of carbon consumption, etc.

Legacy, which took me a bit longer to write, is really saying, ‘Okay, so I’ve looked at climate change, I’ve looked at natural capital, and it’s very obvious that what we’re doing is not sustainable.’ This isn’t going well on climate change. We’re not going to do 1.5 degrees; we’re probably not even going to do 2. On biodiversity, it’s a disaster.

I kept telling people, ‘Do you all agree this is not sustainable?’ Everyone says, ‘Yes, of course it’s not.’ But people are never willing to draw that to its conclusion. That’s my strapline: ‘What is unsustainable will not be sustained.’

What I set out in Legacy is a blueprint of what the economy would look like if it were sustainable. It’s bracing to people who look at the current world and think, ‘If we just tweak it a little bit here or there, we’ll get there.’ It isn’t. It’s not a disastrous world. It’s still a world with growth because technology marches on. But it’s fundamentally different from what we’re doing.

Of course, there’s an obvious conclusion to this, which is, ‘If you think that we’re going to carry on being unsustainable because we won’t do what we need to do, how does it end?’

That’s what I’m writing now. How does it end if we carry on with climate change and biodiversity damage as we are? What does that world look like? What does the rest of this century and the next century actually look like? I can easily say to you, ‘We’re never going to do 1. 5, we probably won’t do 2.’ But what is our world like if it’s 2.8? What is it like if we wipe out half the species on this planet? Nature doesn’t care at all. The planet won’t cease to exist. It’s us that’ll reap the consequences.

It’s a sort of game between optimists and pessimists. The optimists tell you, ‘Don’t worry about it, technology will solve it all.’ There are plenty of these ‘new enlightenment’ people around. The pessimists tell you, ‘We’re all going to die.’ Neither of them is helpful. It’ll be somewhere between the two. Every time I do a presentation someone asks, ‘Are you an optimist or a pessimist?’ It makes me so angry. I’m a realist!