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The Behavioural Expert: Bestselling author Cass R. Sunstein on nudging and climate change

The Harvard academic and bestselling author talks to AIQ about the power of social conformity and what behavioural economics can teach us about tackling climate change.

8 minute read

Cass R. Sunstein
Cass R. Sunstein, Harvard University Professor and Founder and Director of the Program on Behavioral Economics and Public Policy at Harvard Law School

Why do we think the way we think, and believe the things we believe? What is the relationship between freedom of choice and human well-being? How do we weigh the interest of the individual against the interest of society?

These are some of the profound questions that Cass R. Sunstein, Robert Walmsley University Professor at Harvard, has addressed over his long career in academia and policymaking.

Described by The New York Times as “the most influential liberal legal scholar of his generation”,1 Sunstein is arguably best known as an expert in human behaviour. Working with the Nobel Prize-winning economist Richard Thaler, he co-authored the million-bestseller Nudge (2008), which draws attention to how small environmental tweaks can encourage individuals to make better decisions. And Sunstein put these principles into practice in government, serving under President Obama as Administrator of the White House Office of Information and Regulatory Affairs from 2009 to 2012.

In his most recent book, Conformity: The power of social influences, Sunstein turns his attention to the interaction between the individual and the crowd, arguing that our inherent desire to conform lies behind a range of societal ills, from the spread of fake news to the rise of political populism and the failure to tackle climate change.

In this interview, Sunstein speaks to AIQ about the behavioural drivers of conformity, the role of technology in fostering tribalism and how nudging might just help save the planet.

You write that conformity brings us all sorts of social benefits, but it can also “crush what is most precious and most vital in the human soul”. How can conformity be so nourishing, and at the same time so damaging?

There are reasons why conformity can be good. If you look outside and see people are carrying umbrellas, it gives you useful information about the world – it’s probably going to rain today. And conforming provides a kind of social glue. If you wear the kind of clothes other people wear at work, for example, you will be avoiding a risk of opprobrium or ostracism.

Non-conformist thought, action and statements are important as they add to the information that any group has

The problem is that sometimes the group is missing something. Maybe the weather report the other people listened to was inaccurate, and it’s not going to rain. There are more serious examples. I work with private and public organisations, and often conformity pressures prevent them from getting original ideas. There may be someone who is just starting out with the business who knows a new direction would be better, but because she is a conformist – she may be afraid of looking like an idiot or a malcontent – she won’t point out an error in the proposed direction. The reason non-conformist thought, action and statements are important is that they add to the information that any group has.

How should we think about the role of modern communications technology in influencing social conformity? Social media prods people towards greater conformity through creating echo chambers, but it also provides a platform for dissent.

Like the automobile or the nuclear reactor, no simple story would be sufficient. There are great things and not so great things associated with any new technology.

The internet has been a terrific boon. You can learn a lot from websites and social media

With respect to the information a group, country or company has access to, the internet has been a terrific boon. For example, if you are suffering from depression or anxiety, you can learn a lot from websites and social media about how people have coped with their own issues. That can give you comfort – through the realisation that a problem you thought you were alone in suffering is a common one – and information about how to handle it. This is helpful in a society that otherwise encourages you to conform by hiding the problems you face.

It’s also the case people are able to speak out online in a way that can get information into the social bloodstream. During the #MeToo movement, people who might have stayed silent about their experiences due to conformity pressures started to speak out because social media gave them a kind of permission slip to do so. That’s great.

The problem with social media is that it also fuels tribalism

The problem with social media is that it also fuels tribalism. It encourages a kind of “clubbing” by producing a very salient tribal identity. It may be that your self-understanding is no longer, say, as a citizen of the United Kingdom, but instead as a supporter of Brexit. That identity can be a signal not only about how you’re supposed to think of other citizens, but also how you’re supposed to think about 12 other questions that have nothing at all to do with Brexit. The tribal identity works as a shorthand way of figuring out what you think about a wide range of things, diminishing your independence of mind.

What can individuals do to resist the power of conformity? Should we actively seek out those who disagree with us or think differently?

It depends on who we are. If we are leaders in an organisation, to create a norm by which people feel free to add the information they have is a great idea. I noticed that, in government, after I got confirmed by the US Senate and was effectively the boss of an organisation, I suddenly got really smart. I didn’t: I was suddenly perceived as being smart. That was bad because people who worked for me were less forthcoming than they would otherwise be. I learned to be quiet and establish my own receptivity. I also made it clear that being a team player meant providing new ideas, not to echo mine. Leaders can create a norm by which people feel it’s good to say something different.

For each of us, it’s a good idea to try to be ten per cent bolder than we are today

For each of us, it’s a good idea to try to be ten per cent bolder than we are today. All of us, at least once in a while, think to ourselves: “The group is going in the wrong direction, but I might be wrong; and why should I trouble everyone – let alone myself – by expressing an opposing view?” To censor that thought, and say what you think, is a good direction to go in.

You write about how conformity leads certain information or behaviours to “cascade” through groups. How does this work?

Most of us have no direct or personal knowledge of a zillion things that are relevant to our survival. For example, I recently travelled to a place I’d never been before, and went swimming in the water, having been assured there were no sharks there. I had no reason to know this was true, I just relied on others who seemed trustworthy.

Many of the things we think are just a product of what’s been said by people we think we can believe

Many of the things we think are just a product of what’s been said by people we think we can believe. And if a lot of people say something, we would have to have a lot of private information to form the basis of the belief that they’re wrong. That simple point shows how ten or a thousand or sometimes millions of people can be convinced of something just because they are relying on the beliefs of others, forming a very loud chorus. People add their own voices to this chorus through conforming.

Can you give an example of the cascade effect in modern society?

I’ll use an example that has a little controversy associated with it: genetically modified (GM) food. The scientific consensus, and there’s no reason to think it is wrong, is that GM food poses no health risks (there’s also near-consensus that the environmental risks are very modest, although there are some people who think there’s a really small risk of serious ecological harm). Notwithstanding that, there are a lot of smart and educated people in democratic nations who think that they will get sick if they eat food with GM organisms in it. That pervasive belief is the product of a cascade; people are following the signals given by relevant others, people they trust, like their neighbours or friends.

People are following the signals given by relevant others, people they trust, like their neighbours or friends

Nuclear energy is another example. Many people believe that nuclear power is dangerous, but the fear of nuclear power appears excessive compared to the real risks, in my view. Of course, it’s possible my own view is also the product of a cascade effect.

Climate change would seem to pose a particular problem when it comes to conformity and social behaviour, as action depends on people trusting in climate science – a dry and technical discipline in which most have no expertise.  

Climate change is the largest “conforming problem” the world faces today, so let’s try to unravel it a little bit.

The human mind just isn’t wired to think that burning fossil fuels is going to lead to carbon in the air, which is going to lead to a warmer planet

The idea that human activity makes the planet hotter just isn’t intuitive. We are the products of evolution and our evolutionary heritage is well-suited to certain kinds of dangers – lions and tigers for example – but it is not suited to the climate change problem. The human mind just isn’t wired to think that burning fossil fuels is going to lead to carbon in the air, which is going to lead to a warmer planet. It’s a very complicated mental operation.

There are a few things going on that aggravate the problem. One is the collective action problem. If an individual does something to reduce their greenhouse gas emissions, the impact on global warming is very modest, and people get that. To overcome that you’d need a social norm that says: “This just isn’t the kind of thing we do, we are not going to rely on excessive amounts of energy or use coal for our energy rather than solar or wind.” Another problem is that, at least until very recently, in many parts of the world the cost of switching from greenhouse gas-emitting energy sources to cleaner sources has been high.

The way the human mind works, and the way social influences work, make it very hard to combat climate change with the kind of artillery that’s needed

Add to this the conformity pressures. If you are surrounded by and trust in people who think climate change isn’t a big problem, or isn’t going to affect you directly, or isn’t a high priority over other problems, you will think the same. And that makes for the mother of wicked problems. The way the human mind works, and the way social influences work, make it very hard to combat climate change with the kind of artillery that’s needed.

What kind of artillery is needed?

A carbon tax would be a pretty sensible initiative, but even governments like the one in which I worked, the Obama administration, were very cautious about a carbon tax. The immediate cost of a carbon tax is tangible – you feel it – while the benefit of a carbon tax isn’t something you can feel: People have to trust it will eventually be felt.

Based on your theory, could a social cascade lead to shifts in behaviour at the scale needed to make a difference on climate change? Can cascades have positive outcomes?

There can be cascades that lead in directions that turn out to be correct. The idea that coal-fired power plants create serious health risks – which is now widespread – is true, but it is also the product of a cascade, in that large numbers of people have come to trust the expert view that particulate matter a) is dangerous and b) comes from coal-fired power plants. On these important public policy issues, a nation’s direction will turn on the formation (or not) of a large cascade.

How could this work on climate change?

Two examples come to mind.

What drove it was some combination of activism and technical expertise operating hand-in-glove, in a way that was inspiring

One is the Montreal Protocol. Not terribly long ago, the depletion of the ozone layer was thought to be a very difficult problem to solve. Many people thought of it in the way that climate sceptics now think about climate change. The idea that there was a hole in the ozone layer – and that we were going to tax or phase out products that use ozone-depleting substances – seemed like a bizarre, science-fiction notion. But, almost on a dime, that changed. Margaret Thatcher and Ronald Reagan led the charge to phase out ozone-depleting chemicals. The reason they did it is that there was a cascade in which ordinary citizens and policymakers, specialists or not, taking signals from one another, concluded it was worth it. What drove it was some combination of activism and technical expertise operating hand-in-glove, in a way that was inspiring. As of now, the ozone-depletion problem is close to being solved, compared with where it looked like it would be in the early 1980s. Something like that could happen on climate change.

My second example is closer to our topic: the Paris Agreement. I was in the Barack Obama administration for four years and had a connection with it for all eight years; as late as 2010, the notion we could get the Paris Agreement would have seemed somewhere between “very optimistic” and “maybe you’ve been drinking too much”. But it happened. One reason was that the Chinese government was affected by an internal cascade related to air pollution. This was about particulate matter rather than greenhouse gases, but the energy sources that produce one tend to produce the other, so scaling them back makes a difference. The people of China were demanding it and the Chinese government, though not a democracy, listened. Who would have anticipated that? Within the US there was already sufficient support for something like Paris, so with China and European leadership, and getting India on board, suddenly you’re at a point where you can make it happen worldwide.

Now, the Paris Agreement isn’t getting us where we need to be, and the Trump administration’s scepticism on climate change has been a real problem. But to turn Paris into something that looks like “Paris on steroids” is possible – don’t be surprised if something like that happens within the next five to ten years.

Your book Nudge brought attention to the power of behavioural solutions to ingrained social and economic problems. Could “nudges” make a difference on climate change?

If we can get each person to cut their carbon footprint by a non-trivial amount, then significant progress towards less destruction across the planet will be made

Absolutely. Automatic enrolment onto green energy tariffs, for example, can create very significant movement when it comes to reliance on green energy sources. We know this from one of the world’s leaders on climate, Germany, where a number of energy companies are nudging people to use clean energy by automatically enrolling them in solar and wind. People have the opportunity to opt out and go for coal-powered energy, but the data shows they don’t, even if the green option is a little more expensive. If that can happen in Germany, it can happen all over the world.

There are other small things that, if aggregated, can make a big difference. When hotels say they are not going to wash your towels or sheets every day unless you ask them to – that’s a nudge. The reduction in greenhouse gas emissions that come from that sort of thing, now that large numbers of hotels are doing it, are non-trivial. So much of the carbon emission problem is the product of individual consumers’ behaviour, aggregated across large populations. If we can get each person to cut their carbon footprint by a non-trivial amount, then significant progress towards less destruction across the planet will be made.

No single intervention can do what needs to be done.  But if you aggregate the number of interventions which are usable, including energy efficiency regulations capable of massively reducing the amount of energy used by refrigerators, microwave ovens or washer-dryers, and combine them with regulations that can dramatically reduce emissions from automobiles, and restrictions on emissions from coal-fired power plants, then huge progress can be made.

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