 I'm Stephen Lewandowski, I'm a professor of cognitive science at the University of Bristol in the United Kingdom and I do research on how people think about climate change and misinformation and I'm also doing research on the effects of uncertainty in the climate system. So when it comes to the drivers of belief or acceptance of scientific findings in particular climate change, then what we find is that one of the most important factors is a person's worldview or you can call it a political ideology, their belief in things such as the free market and it turns out that in particular in the case of climate change that people who are very enthusiastic about free markets and who think that government should not interfere with free markets, that they tend to reject the findings from climate change, climate science based on that ideology and it's a very strong effect. It's a huge effect. In some of my data it explains two-thirds of the variance. Now what that means is that if I know somebody's belief about the free markets I can reduce my uncertainty about what their climate change attitude is by two-thirds. So there's a huge correlation there between those two variables and that is one of the main drivers. There are other drivers, one of the smaller ones in terms of statistical magnitude but one that is significant is people's willingness to accept conspiracy theories. Turns out that people, there is an association between people's endorsement of conspiracy theories and their rejection of science. Now that association is quite strong when it comes to vaccinations, for example, that people who endorse various conspiracy theories are quite likely to reject the notion that vaccinations are safe and are saving lives. When it comes to climate change that association is smaller but it is significant and it is significant in particular in the public sphere. A sitting US senator has written a book that's entitled The Greatest Hoax, How the Global Warming Conspiracy Threatens Your Future. Now that's pretty explicit. If you call something a hoax and you talk about a conspiracy, well then you probably think that there is a conspiracy among scientists to invent this hoax called climate change and that is precisely what this person is saying in his book. And that's not an isolated instance. If you look at the discourse on climate change blogs it is suffused with the attributes of conspiratorial thinking. This notion, this overriding suspicion of scientists that scientists are, they're all cheats and they're all making this up and they're all trying to scare you for, well, I don't know why but there is this suspicion and fear and paranoia that people express when they're rejecting climate science. And so that is a small but I think in public life significant driver as well. Well, I've performed a number of studies that looked at the association between acceptance of science and people's tendency to endorse conspiracy theories. And one of those involved visitors to climate blogs and the other one involved a representative sample of Americans, a thousand US representative respondents. And what I found in both studies is the same thing and that is that as people are more likely to endorse various conspiracy theories, for example that MI5 killed Princess Diana or that the UN is trying to create a world government, that sort of thing, the more people tend to endorse that, the less likely they are to accept scientific propositions. Now that association is very strong for vaccinations, for example. People who reject the fact that vaccinations are saving lives and that they're safe. People who reject that tend to disproportionately endorse various conspiracy theories. The same relationship exists for climate change, but it is somewhat smaller statistically in those samples. The response to my studies when they were first published was very, I was delighted by the amount of confirmation that I received in the form of people on so-called skeptic blogs saying things that were entirely conspiratorial. And it was a real eye-opener to actually see that in action directed at oneself. And one of the things about conspiratorial thinking, one of the characteristics of it is that the scope of the conspiracy tends to broaden over time. And that's what happened in the case of my paper very intriguingly because what happened was that people who didn't like my paper complained to my university where I was at the time, the University of Western Australia, alleging all sorts of things, that I wouldn't release my data and that God knows what else I can't even remember. But just anything you can think of was put into these richly formatted letters of complaint with a lot of different fonts and exclamation marks and so on. And the university examined all those complaints and didn't uphold a single one, of course, and said, well, you know, there isn't anything to complain about here. That was properly done research. And now what's happened is that on the blogs, the University of Western Australia is being maligned and smeared and is now pulled into this bigger conspiracy and there were people even expressing the opinion that I'm in cahoots with the Australian government and that I'm a government agent or something trying to suppress free speech, which is interesting in and in itself, but it's also paradoxical because throughout the last couple of years that I've been doing research on this, the people who reject climate science have made every attempt to curtail my freedom of speech and my academic freedom and to basically silence my work. And that is not unusual at all. That is again a chapter in the playbook of science denial. That is how it is done. That is how I have colleagues who do research on tobacco and the health consequences of tobacco and they are subject to exactly the same frivolous attacks and freedom of information requests and complaints to the university as are people working in climate science. As always in these things, there are multiple people working on this and if the evidence is converging on the same conclusion, then we can be more confident that the effect is for real. And so for example, Smith and colleagues have written a paper where they asked respondents to tell them what's the first thing that comes to mind when I say climate change. And it turns out in that study that one of the primary associations that people came up with to the word climate change was hoax or conspiracy or other conspiratorial words when they were rejecting the science. So the two tended to go together and there's discourse analyses of the content of newspapers. There's a study done in Australia by Elaine McHughan who found that there are conspiratorial themes in newspaper coverage that is rejecting climate science. That's a very strong theme. And so there are multiple converging lines of evidence and of course all you have to do is you have to look at the title of books as the one that I just read out, The Greatest Hoax, How the Global Warming Conspiracy Threatens Your Future. That was written by a sitting U.S. Senator, I mean you can't be much more explicit than that. So some of the characteristics of conspiratorial thinking or conspiratorial discourse are well understood and there is a number of them. I think the most important one, the most powerful one, is an overriding sense of suspicion. Something that goes beyond skepticism, that goes into suspicion and can approach paranoia even and that is that nothing will be accepted at face value if it comes from somebody who's presumed to be involved in this conspiracy. So it doesn't matter what you say if you're the target of a conspiracy theory because whatever you say will be taken with the greatest suspicion and it will not be seen in the light in which it is intended. So that I think to my mind is the most important one. There are others of course. The second one is this idea that as evidence against the conspiracy becomes available, the conspiracy is just seen to become broader and broader. So rather than like if I complain about somebody an academic and I send a complaint to the university and the university replies saying well sorry there is nothing for you to complain about, then rather than taking that at face value, an element of conspiratorial thinking then would be to say the university is in on the conspiracy. And I have seen that happening firsthand in the response to some of my research that initially I was the target and then it became bigger and bigger and ultimately some people said I'm working for the Australian government and that I was running a media organization in Australia and that the university and the Australian Research Council are all in with Lewandowski to do these things. So that's the second attribute of conspiratorial thinking, this broadening of scope. Another one is that people who are in this world of conspiratorial thinking, they see themselves as victims. They feel victimized. That is very common amongst people who deny the findings from climate science that they are saying gee we're being silenced, we're the victims here, no one is listening to us. When in actual fact they're saying whatever they want to say on their blogs and to my knowledge no one has ever interfered with that. And at the same time they are however actively involved in attacking scientists and trying to silence them and trying to get their papers retracted and to stifle free speech on the part of academics while feeling victimized. So that's another aspect of it. Further aspect is of conspiratorial thinking is that there is this paradoxical belief, this incoherent belief that on the one hand the conspirators, the bad guys are small in number and you can name who they are. But at the same time they're all powerful and they're absolutely everywhere. So you have this interesting contrast between on the one hand identifying specific scientists who are part of this conspiracy such as myself. But then at the same time the few people that are being identified as in the conspiracy they are supposed to be all powerful and we are somehow the two or three of us that are being named. We're somehow running the world government and the United Nations and in my case the Australian government and so on. So there's this paradox of a tiny number of people that are at the same time all powerful and ever present and we're permeating the entire world with our ideas. If I believed anything that people say about me on the internet then I would have to somehow put myself into handcuffs and hide in the basement for the rest of my life. But fortunately I know better than that. One of the interesting things about the rejection of science is that it tends to come in clusters. It tends to be the case that if a person is rejecting the finding from climate science then chances are they're also going to reject some other well established scientific finding. In my studies I find a fairly consistent clustering between beliefs pertaining to science. So somebody who does not accept the findings from climate science is also quite likely or more likely than others to reject the link between tobacco smoking and lung cancer. And that's not entirely surprising if you just look at the websites of some free market think tanks. You will often find that next to each other you have literature that is doubting the link between tobacco and lung cancer and that is questioning the link between greenhouse gas emissions and climate change. And the motivation is the same in both cases. The science is rock solid but the response to the scientific findings might involve regulation of industry or taxation or other things that are anathema to people who believe that the free market is the only thing by which anything should ever be regulated in the world. One of the things we find is that people reject scientific findings because of their political fundamental beliefs about how the world should operate. So climate science is rejected primarily by people who are endorsing free markets to an extreme extent. Most people tend to be more focused on the conservative side of politics and conservatives in turn are more likely to reject the findings from evolution and are instead preferring to view the world not through scientific terms but through religious terms. So there is a clustering between the rejection of evolution and the rejection of climate science based on those political religious beliefs because those things tend to cluster together. Now one crucial question that society is confronting is how to deal with the expressions of denial that are so common on the internet and on blogs. The answer to that I think is that it is absolutely essential to be driven by data, by research, by empirical findings and to look at what the data in cognitive science and psychology, what they tell us about the problem. I think it is crucial not to be misled by one's own intuitions about it. Now let me illustrate that by giving you a couple of examples. The first thing is to understand how many people are actually rejecting the findings from climate science and then to look at what the perceptions are that people have of those opinions and let me explain that in some detail using an Australian study done by Zoe Liddiston and colleagues a couple of years ago. Now they surveyed repeatedly 5,000 Australians at representative samples. That was a very large sample. It was done nationally. It was done over again and it gave us a very good insight into what people are thinking about climate change. Now it turns out that in their data consistently the proportion of people who denied that the climate is changing was very small. It was less than 10%. It was somewhere between 5% and 10% plus minus a few points. So it is a very small number of people. Somewhere between 1 in 20 and 1 in 15 is rejecting the fact that the climate is changing. Now what's interesting is that if you ask those people about how many others they think are sharing their opinion, the answer is that they think 50% of the population is sharing their opinion. So the tiny number of people who actually are rejecting climate science, they think that their opinion is shared by half the population. And that inflation of an opinion from what it actually is to what it is perceived to be. So inflation also occurs for people who are accepting the overwhelming scientific consensus on climate change. They too think that 1 in 5 or about 20% of people are rejecting climate change when in fact that's not the case. Now that's extremely important number one to be aware of that, that the number of people who reject the science is actually relatively small. In surveys, representative national surveys. And what follows from that I think is a number of things. First of all it probably is unnecessary in order to do the one thing that matters which is to mitigate climate change. In order to do that you don't have to change the minds or opinions of 5% of the population. That's absolutely unnecessary. Politically unnecessary, it is a waste of resources to try and communicate or convince people who reject scientific evidence because the reason they reject the scientific evidence is not because they've evaluated the evidence rationally. It is because they're motivated to reject it by other variables. So trying to throw more evidence or more data, more scientific knowledge at those people is pretty much a hopeless task. So instead it is important to talk to the other 90% of people who are not denying that the climate is changing. And it is important for them to know first of all that they're in the vast majority themselves. They also have to know that there's a vast consensus among scientists because it turns out that telling people about the consensus makes them more aware of the science and makes them more accepting of the science. We've done that in multiple experiments to show that that is the case. And the final thing that research on misinformation suggests is that you have to explain to the majority of people why there is a small but vocal minority that is denying the science. So I think it's very important for the public to understand that those people are motivated by factors such as personal ideology, that there is this association between conspiratorial thinking and the denial of science. It is also very important to understand that a lot of this opposition to climate science is organized by vested interests and political networks. There's a recent paper by Robert Broly that painstakingly went through tax returns filed by a huge number of so-called think tanks and lobbying outfits in the United States. And what he concluded from his scholarly research is that up to a billion dollars a year goes into a machine, into a propaganda machine, part of which is used to deny climate science. And I think that's absolutely crucial for the public to understand that a lot of this is motivated by money, by vested interests, by ideology, by other psychological factors, and that none of the opposition to climate science is scientific. One of the reasons why it's very difficult to change the mind of people who are committed already to rejecting the science, one of the reasons that's very difficult is because they're challenging their worldviews if you are trying to change their belief about climate change. Now, people reject the science in the first place because it is incompatible with their deeply held worldviews. Most people who reject climate science do so because they fear not for the planet but for the interference with the economy, with the free market, if we did something about climate change. And to do something about climate change, we have to impose taxes, regulations, we have to curb emissions, we have to transition to clean energy. And even though the vast majority of people in surveys actually want that and they want a transition to clean energy, for some people that's incredibly threatening because they think that any taxation or regulation is the first step in a slippery slope towards communism or some other horrible thing. And so that's how they take on this antagonistic stance towards climate science in the first place. Now, if you then, as a researcher or communicator, present them with more evidence that climate science is real, then chances are that the recipients of the message are digging themselves deeper into their existing position and actually believe even more strongly that that is not the case. And we have the experimental data to show that in a lot of different circumstances. It doesn't just have to be climate science. It's whenever people's worldviews are at stake, then presenting them with corrective information can have a so-called backfire effect of making them believe the mistaken information even more strongly. So that is another reason why engagement with people who deny climate science is inadvisable because you're just strengthening and reaffirming their belief if you're not careful with your message. So one of the key issues that faces a communicator isn't just what to say. It is also what to say to whom. The target audience in climate change matters a great deal. And different audiences require a different message. If you want to talk to scientists from other disciplines who are not in climate science, then presumably presenting them with scientific information is the way forward. But if you're talking to the public at large, talking a bit more about atmospheric chemistry is probably not going to do the trick because, frankly, they might not understand it. I don't understand all the nuances of atmospheric chemistry. So why should the public? So what the public has to do is they sit there and they have to make a choice about there's all these messages out there, who am I going to trust, what am I going to listen to, what am I going to believe? It turns out that most people in survey after survey after survey in the entire western world, one of the groups of people they rank most highly on a trust scale, the people they find most to be trusted in society are scientists. Way ahead of politicians, lawyers, used car salespeople, even ahead of clergy in most societies. And so if the public knows that the scientists have formed a consensus on climate change, then that allows them to rely on that trust that they have in scientists anyway and to accept the fact that, yeah, we have a problem and we should do something about that. And it turns out that there is a number of studies that have looked at this. And in pretty much all cases that I know of over and over again, if you tell people that there is a scientific consensus on climate change, then that is affecting their acceptance of the science. And we know that people's perception of the consensus is related to their policy preferences. The more people think there is a strong consensus among scientists, the more likely they are to support mitigation measures. Now, one of the interesting things in this whole area is that the people who deny climate science call themselves skeptics. And that's quite interesting because their actions aren't skeptical at all because they will accept with great gullibility pretty much any false information about climate science that's out there, even if it is mutually incoherent. One of the intriguing attributes of climate denial is that very often the very same people will start out denying that it's getting warmer. Then five minutes later they will say, oh, but the warming is all natural, even though they just deny that there is any warming at all. And then the next day they'll say, ah, yeah, but the warming is good for us. So there is this sort of incoherence of messages within the denial community, any one of which is being latched upon. It's the sort of quantum cognition where anything goes at any time, provided I can deny the implications of climate science. That's not skepticism. That's being extremely gullible because you're believing anything that will fit into your worldview. Now, true skeptics are different because true skeptics reject things that are false, but they're also endorsing things that are true. And that is the most important distinction between skepticism and the rejection of science. And some of my own work has shown that skeptics have a what we call a greater signal to noise ratio. That is when they're presented with information that has a mix of signal, true stuff, and a lot of noise misinformation, then skeptics are less likely to believe things that are false, but they're also more likely to believe things that turn out to be true. So they're differentiating more between true and false information. So being skeptical doesn't mean you say no to everything. Being skeptical means you look at things, examine them, and then you say, well, hang on, I'm skeptical of this. No, I'm not going to believe that. But at the same time, you're saying, hang on, that looks right. I'm going to believe that. So skepticism allows you to choose between what is likely to be true and what's likely to be false. And of course, skepticism is the underlying principle of science. We as scientists are skeptical about things. We try to knock theories on the head and try to show what's wrong with them. That is what science is about. And the whole process of peer review, that you have to subject your work to skeptical review by other experts. I mean, that skepticism is built into the scientific process. And that is why scientists skeptically on the basis of the evidence have come to the conclusion that the globe is warming from human greenhouse gas emissions. So it's very challenging to correct misinformation. And it is challenging for a number of reasons. And one of them are fundamentally cognitive. That is, even before we get to ideology, worldview or your self interest or anything else that might affect your belief, the very act of trying to change your mind and update your memory is very difficult. It is cognitively challenging and complex. So we can do experiments. We've done this countless times over the last 10 years or so. We can do experiments in the laboratory where we give people a story about some fictitious event and halfway through the story, we say, oh, by the way, what you just heard was false. And then a little while later, we ask people some questions about what they made of this story. And it turns out that even though we tell people something, hang on, that was false, they still rely on that information later on to draw inferences from the story. And what's even more intriguing is that they do that even though when we ask them, they can tell us that the story had been corrected. So they will know that we said the moon is not made of green cheese. But later on, they're still going to act as though the moon is made of green cheese when we ask them inference questions. Why is that? Well, it's because as you're listening to a story, you're building an event model, a mental model of the event as it is unfolding. And if all of a sudden you find out that something is false after you've already built a model of the story in your head, then you're confronted with having to put a big hole into that story. You know, you think you know what's going on, and all of a sudden somebody tells you, hey, that's false. And then you sit there, you go, wow, OK, great, you told me it's false. But you don't quite know how to update your event model. If all you're given is the information that something is false. Now, if you tell people not only is this false, but this is the alternative that is actually true, then they can update their event model. So let me give you an example. If I talk you through a story about this jewelry theft, you know, somebody goes on vacation, they leave the window open, they come home from their vacation and the diamonds are gone. And then I tell you that the police are they think it's an inside job and the main suspect is their own son who was supposed to be house sitting, you know, and so on. If I then tell you that, oh, the police have cleared the son of this suspicion, then guess what's going to happen? What's going to happen later at test is that you will still act as though the son was the thief, despite the fact that you were told no. However, if I give you the same story, but I add to the correction that not only was the son cleared of the suspicion, but somebody else, a neighbor was arrested for the crime and has confessed. Then the son will be psychologically exonerated. You will no longer act as though it was him who did it because you have an alternative. And that is why it is so crucial when you're dealing with climate change and climate change disinformation. That is why when you when you rebut something, you also have to explain to people why it is that they shouldn't believe this misinformation and what is true instead. And so providing an alternative is crucial. And making people skeptical of the source of misinformation is crucial, which is why it is so important to explain to the public why people are denying the science and what's behind that and what's driving that. I took my first psychology course in 1977 in the sort of Jurassic period of modern civilization. And well, at first I thought I was going to learn something about dreams and what makes people take and all our fears and phobias. And I don't know, maybe I thought that was a good way to learn that. I had to talk to women or something. But then I discovered that psychology wasn't about that at all. And it was about something far more exciting, namely trying to do science and trying to understand how the human mind works. And so I got hooked on that. And then somebody told me something about computers back in 1977. It wasn't at all obvious that I mean, you know, half of us students didn't know what a computer was. And then somebody told me and I thought, gee, that's kind of funky. And so I enrolled in computer science and introductory programming in Fortran 3, I think, on punched cards. And then I thought, gee, this is really, really cool. And actually most of my undergraduate, much of my undergraduate education was in computer science and maths, not in psychology. And then I combined the two and I have been pursuing both computer science and maths and psychology ever since for the next 30 years or so. And that's what's known as cognitive science. That is what cognitive scientists do. We use computational tools to try and understand the mind. We use experimental methods to test our hypotheses. And when I became interested in climate change because of my work on skepticism five years ago or so, I learned that geophysicists do things a lot. A lot of times, in exactly the same way as cognitive scientists, they are trying to model a complex system and they test their predictions by experimentation. And so it was a very natural blend for me to model cognition and now to model on a small scale the climate system and to publish in climate science as well. The most interesting question to me is quite possibly not psychological in nature, but it is basically political. And that is to find a political path by which people can learn that we do have a problem, that it is a solvable problem, but that to solve it we have to ignore the opinions of a lot of very vocal people. And we have to find a way to prepare people for change, for a transition to a sustainable economy and clean energy. And we have to find a way of illustrating that and finding a path to the future. Well, I think the most important thing to my mind is for scientists, climate scientists, to realize that the public sphere is a wash with agents who are not acting in good faith, but who are not interested in dialogue, who are pursuing their own interests, whatever they may be, and for whatever reason, and who will not respond to communication in the same way that you and I would engage in the dialogue. I think that's a crucial realization that people have to, scientists have to, unfortunately, come to that realization. And certainly tobacco researchers know that. AIDS researchers know that, that there are some actors out there who are just not talking the same language and never will. And climate scientists, I think, have to realize that to understand what's going on. And some of them do very much, but others may not. The second thing I think is that I think climate scientists should reinforce what it is we do know and then say explicitly what it is that we don't know. At the moment, the public discussion of science and I think climate scientists themselves focus entirely on the uncertainties and the things we don't know. And of course, for a scientist, that's a natural thing to do. I do this all the time in my professional work. I don't talk about things I know about human cognition unless I'm being interviewed. When I talk to other scientists, I'm talking about the problems I'm working on and by definition, they're the things we don't know. It's the frontier of knowledge. But in public discourse, that's often mistaken for a lack of knowledge. Just because you're discovering new things doesn't mean you don't know anything. Quite on the contrary, it means you're building on a large body of knowledge trying to add to that by discovering new things. And so, in terms of public communication, I think it's quite important and strongly recommended for scientists to say, well, we actually know this, that, and that, and that is enough for us to act. I think those are the crucial messages that people have to get across. Climate science is 150 years old. We know that CO2 is a greenhouse gas. And if that were false, then airplanes would fall out of the sky because the rest of physics would be false. But it isn't. Airplanes fly and CO2 is a greenhouse gas. We know that has thermal properties. We know that's going to warm the planet with further fossil fuel emissions. There's absolutely no doubt about that happening. And the consequences are going to be not too good unless we do something about that.