We must stop saying ‘The science demands…’

‘To say that the science demands a certain policy response to climate change is just a wrong reading of the relationship between science and policy.’

Mike Hulme, professor of climate change in the School of Environmental Sciences at the University of East Anglia, is a passionate advocate of science. Yet, as he tells spiked, when it comes to climate change, too many people expect too much of science. Physics and ethics seem to have become conflated in the climate change debate. We see politicians expecting science to determine policy; we see environmental campaigners, armed with peer-reviewed papers, expecting it to win all the arguments; and, in turn, we see so-called sceptics expecting their science to refute the green vision of society. But for Hulme, author of Why We Disagree About Climate Change, science cannot, and should not, be expected to do these things. It is no substitute, he argues, for politics or for moral judgements.

‘The phraseology that I object to – because it’s inappropriate – is “the science demands this” and “the science demands that”, as though the making of climate policy, or policy in general in fact, is a simple process of translating scientific evidence or scientific knowledge claims directly into policy. In no area of policy is that the case – least of all in climate change, where the making of policy has to bring in a much wider range of pieces of evidence and also political and ethical considerations.’

So how should we grasp the relationship between science and policymaking? ‘I do think that scientific knowledge about climate change is very important’, says Hulme. ‘Science is a unique and very powerful way of bringing understanding to bear on how the physical world works. Scientists have been able to reveal the fact that humans are an influence on the climate system and are likely to continue to be so. And that evidence, that knowledge, should be brought into public and policy deliberations. But it then has to be interpreted alongside these other considerations – political, ethical, moral and so on.’

Hulme is keen to point out the limits to what climate science can tell us about the future: ‘Scientific knowledge around climate change can only speak with large uncertainty margins about what may or may not happen. Yes, climates will continue to change in the future because of human emissions. But putting exact numbers on changes, and therefore predicting what risks lie ahead, is extremely difficult for science to do. So it’s important for scientific knowledge to be adequately hedged in public debate and policy discussion with appropriate caveats and caution about uncertainty.

‘That is not the same as saying that this knowledge is not useful or that it should be ignored. Most scientific knowledge is uncertain. Most scientific insights are hedged with caution or uncertainty. But that’s exactly why judgement – political, ethical, moral judgement – has to be used for making policy.’

He goes further still: just as science cannot make decisions for us, he says, so the arguments about climate change today ought not to be grasped as being scientific in origin: ‘I certainly think politics and ethics explain why people have so many different positions on climate change. I think that deeper-seated issues [inform the arguments]: different cultural perspectives on the relationship between humanity and the natural world; different attitudes to, for example, the responsibilities that humans have as opposed to those of the divinities that people believe in – the role of religion becomes important here.

‘Even in a secular setting, people have very different attitudes that inform their relationship to climate change. For instance, some see nature, and therefore the planet, as something that is fragile and easily dislocated. Others see that nature is actually quite robust and resilient. And then there are different attitudes – secular or religious – to technology. People have very different views on the ability of technology to mitigate against risk and danger. Some people see technology as inherently loaded with further problems and complications and unintended side effects.’

Given evident disagreements about climate change, and climate change-driven policy, how should we understand the meaning of a scientific ‘consensus’? ‘In science’, Hulme says, ‘phrases such as “the scientific consensus” or “the IPCC consensus” are frequently used. I do think it’s important to understand what this process of consensus-making in science is all about. There are criticisms from both sides of the debate around this thing called scientific consensus. Some people criticise it by saying, “Well, science doesn’t work by consensus, science works by testing, by experimentation, by falsification. It’s not a democracy. Ninety-nine per cent of scientists can be wrong and one per cent might be right.” So actually, some people criticise the IPCC process because it’s using an inappropriate method for producing knowledge claims. Other people, meanwhile, actually interpret consensus as meaning certainty. I think it’s important to unpack what is meant by consensus in science.’

Ironically, he says, the search for a consensus on the science of climate change is evidence of deep divisions on this issue. ‘Consensus in science only makes sense if there is disagreement amongst experts’, he says. ‘If all the experts agreed, you wouldn’t need to go through this process of consensus-making. Hence we don’t need to go through a process of consensus-making around the laws of gravity. But a process of consensus-making around climate change is important because there is disagreement. So actually consensus assumes disagreement amongst scientists.

‘But what the process of forming a consensus does do is establish where the centre of opinion lies, given the spectrum of views and judgements. So it’s not just about consensus knowledge, it’s about the spectrum of beliefs. And those two things actually work together: there’s a wide spectrum of beliefs about aspects of climate change, but nevertheless this is where the centre of gravity lies. And that’s a slightly more subtle position than simply saying “the IPCC consensus is this or that”.’

Yet if consensus is predicated upon disagreement, why, politically, is there so much anxiety about anyone appearing to challenge the consensus, with people branded as ‘deniers’ and modern-day heretics if they dare to question what some greens mistakenly consider to be concrete agreement amongst leading experts? ‘One of the reasons for that’, says Hulme, ‘is because of this belief that there is a specific relationship between scientific knowledge and policy. As a result, it is argued that you have to have clear and certain scientific knowledge that will translate into clear and certain policy. And if the science is presented as being not clear and not certain, then the whole argument, or the whole policy, breaks down.

‘And that’s why so many of the battles, so many of the ideological battles, are fought through the proxies of science and scientists – because people think that if you win that battle, then you’ve won the policy battle. This again is an inappropriate understanding. Actually, the ideological battles, the policy battles, have to be held on the territory of politics, ethics, worldviews and beliefs. That’s where the legitimate battle should be held.’

Hulme cites the 2007 Stern Review as an example of the worrying effacement of political and ethical debate in favour of apparent scientific facts: ‘It offered a very powerful economic case for early and urgent action on climate change. But actually what didn’t get debated in the Stern Review – and it should have been – was the ethical dimension that underpinned the economic analysis. There was just so much focus on the numbers. But the argument should have been held around the ethical decisions that Lord Stern’s team made about discounting the future at very low discount rates or using inequality of risk parameters that seemed to give very little weight to the contemporary poor in favour of the unborn poor. Those are not matters of science, they are matters of ethical judgement. And you can get a radically different set of policy pronouncements depending on where you fall on that ethical spectrum.

‘So really, what the Stern Review should have catalysed is a major public debate on how we value the future, how we value the present, how we value the contemporary poor versus the unborn poor. And Stern took a very particular ethical line. And you can agree with it or you can disagree with it, but it should have been centre-stage. Instead, the final arguments were drawn from economics again, as though that provides the one single route for policy development.

‘The battle, the argument, the public debate’, Hulme argues, ‘should be around these matters – values, beliefs and ethics – rather than continually reverting back to the science to try to provide the certainty and the clarity. Because science, particularly in this area of complex systems, like the Earth system, is never going to provide that kind of certainty.’

All of which raises the question: why isn’t the battle, the argument and the public debate about the Good Life, about how we should organise society, being had in its own terms? Why is it being had through the prism of climate science?

‘This question opens up a much bigger set of issues which don’t just pertain to climate change’, he answers. ‘People have been thinking and writing about this in the much wider context of the political, cultural and ideological mood at the end of the twentieth century and the beginning of the twenty-first. It involves the erasure of ideological difference in political life and the accompanying trivialisation of politics. It involves the unwillingness of Western liberal democracies to engage in debates and arguments about fundamental questions of value, purpose and meaning, because, to an extent, we’ve all bought into the liberal capitalist model which delivers very comfortable lives for most of us.

‘So I think that it’s the wider cultural phenomenon in which climate change sits that helps to explain why we’d rather argue about whether this is good science or bad science or whether a scientist is being influenced by oil companies or by environmental alarmists. We’d rather have those sorts of arguments because they seem more comforting and less challenging than arguments about the scandal of global poverty in a world of affluence, or the question of whether we can really secure unfettered capitalist growth at three per cent of GDP per annum for the next 300 years. Those much more challenging and unsettling arguments we’d rather not have. And so the convenient arguments, the much more narrowly bounded ones about good and bad science, take their place.’

Mike Hulme is professor of climate change in the school of environmental sciences at the University of East Anglia. He is author of Why We Disagree about Climate Change, published by Cambridge university Press. (Buy this book from Amazon(UK).

Tim Black is senior writer at spiked