Book Summary: How to Talk to a Science Denier

This is a summary of some of the main points from the book How to Talk to a Science Denier by Lee McIntyre (MIT Press, 2021).

The main theme of the book is the exploration of approaches to have a meaningful dialog with people who have adopted certain anti-science beliefs. The focus of the book is on two big problem areas in today’s society: opposition to vaccines and denial of the urgency of action on climate change.

Lee McIntyre is a philosophy professor, social science researcher, and the author of a number of books on the philosophy of science, and more recently, several books on how scientists and non-scientists deal with questions of truth and belief (Post-Truth (2018), The Scientific Attitude (2019)).

In McIntyre’s “science denier” book, he attempts to gain a better understanding of the people who deny scientific facts and research results. He starts with the most extreme and comical (Flat Earth believers) and then progresses to discuss people with more subtle delusions (anti-vaxxers, climate change deniers, and Trumpists).

As a non-scientist (or at least, not as a non-physicist), McIntyre starts his book by recounting his visit to a Flat Earther convention, where he tried to gain a better understanding of how and why these people came to their way of looking at the world. He explained that if he could come up with some approaches to combat the most extreme science deniers, he might learn some techniques that would help address a much larger community of believers in various conspiracy theories.

In the rest of the book, McIntyre outlines some promising approaches for fighting science denial. The primary approach is *not* to convince the deniers of the true facts by giving them more scientific information and expert opinion. Deniers are already dismissing data and opinions that clash with their favorite theories, so more data and more experts won’t sway them. McIntyre discusses the value of engaging in non-scientific discussions to understand the connection between deniers’ sense of identity and their irrational beliefs. There are no easy answers to defeating attacks on science.

Two results from psychological research

McIntyre searched through the literature on “changing people’s minds,” and he found two interesting research results.

First: The idea of the “backfire effect” has been debunked. A few psychological studies (in particular, a 2010 study by Brendan Nyhan and Jason Reifler [“When Corrections Fail: The Persistence of Political Misperceptions”] seemed to indicate that people with a conservative political view not only rejected “corrective data,” it actually triggered them to increase their belief in the old erroneous data - when the corrective data contradicted their conservative values. Their original conclusion: “Some partisans not only refused to give up their original beliefs but held on to them more strongly once they were challenged.”

But a series of later studies failed to repeat these research results, in particular a 2018 paper by Thomas Wood and Ethan Porter [“The Elusive Backfire Effect”]. In fact, Nyhan and Reifler changed their view in 2018, and they worked together with Wood and Porter on new research in this area. They all agreed that partisans are “resistant” to data that contradicts their beliefs, but they haven’t seen that partisans “double down” on their original views in the light of contradictory data.

Second: McIntyre explains that an attempt to argue about facts can turn into an attack on the identity and values of the person holding unscientific views. For example, many Republicans deny climate change and feel that “the truth about climate change” is a threat to their core pro-business ideological identity. It makes it easier for them to say “I don’t trust the source, they hate us.”

There was another 2017 study by Nyhan and Reifler [“The Roles of Information Deficits and Identity in the Prevalence of Misperceptions”] that tried an interesting approach - presenting graphs about climate change instead of text-based information. This seemed to be easier for Republicans to accept. One of the important things to consider is the “manner of presentation” - and perhaps keeping the presentation emotionally neutral will make it more persuasive.

Science denial and the post-truth movement

McIntyre things that science denial has been a contributing cause to the “post-truth” attitudes in parts of society today, especially among conservatives. There are people who resent experts who tell them how they are supposed to think. They identify the experts as members of a self-elected “elite,” and they don't want to be victims. McIntyre cites Tom Nichols’s book, The Death of Expertise, which explains that post-truth culture is mainly about the grievances of the non-experts.

Sources of anti-science beliefs; reasoning errors

McIntyre spends some time in the book discussing the “sources” of science denial - how a science denier comes to believe in crazy things, like a Flat Earth. McIntyre has found two cases where industry groups have created an organized campaign to create doubt in scientific conclusions. The first campaign was about the link between smoking and cancer, and the second was about human-caused climate change.

The tobacco industry created an effective misinformation campaign to deny scientific research in the 1950s and 1960s about the negative health impacts of smoking. In the 2000s, a similar campaign against climate change research tried to counter the mounting evidence of carbon dioxide’s impact on climate - this campaign was launched by the fossil fuel industry. In both of these campaigns, the attacks on science fell into five different categories:

This list comes from a paper by Phillip Schmid and Cornelia Betsch [“Effective Strategies for Rebutting Science Denialism in Public Discussions,” Nature Human Behavior, 2019]. Schmid and Betsch have found that the best way to mitigate denialist beliefs is to take each anti-scientific argument and connect it to one of the these five science-denial techniques. They see this “rebuttal” process as an easier way to fight scientific misinformation, whether or not you are a scientist.

The idea is to *listen* to a science skeptic: ask open questions and get the skeptic to explain their thought processes and evidence. Some misleading arguments are pretty easy to head off.

There are many other areas of science denial that are not the product of an organized industry campaign, just an undirected grass-roots campaign spread through news stories and social media. One example is anti-vaccination beliefs, which has a wide-ranging set of adherents (people who have an anti-big-government bias, are suspicious of the pharmaceutical industry, or are fixated on possible vaccine side-effects), and they find backing from many sources (liberal or conservative celebrities who campaign against vaccines, stories on social media, papers and studies from fringe scientists). For some vaccines, there is a political divide: anti-vax sentiment for the COVID-19 vaccines have become intertwined with arguments about mask mandates and other public health measures.

But even if anti-vax beliefs are not being directed by a single industry campaign, the “five categories” of anti-science attacks are still being employed to convince people to deny science.

Liberal science deniers

McIntyre points out that people with liberal political beliefs are capable of science denial. His book includes a chapter about GMOs (genetically modified organisms - otherwise known as genetically engineered foods).

Almost all of the research on GMOs has found that they are safe, but many people don’t accept the scientific evidence. In the debate about GMOs, there are some legitimate policy questions about GMO copyrights and reduction in genetic diversity, but naysayers are still citing studies with cherry-picked data, fake experts, and unreasonable standards of scientific proof.

McIntyre’s observation: “It wasn’t that anti-GMO activists were piggybacking on some suspicious scientific finding. Instead, the original opposition to GMOs occurred before any empirical evidence was available, and continues to this day despite the fact that there is still no evidence they are harmful.” McIntyre agrees with the opinion of historian Mark Lynas [from his book Seeds of Science] - the moral objections to genetic engineering came first, and the opponents of GMOs are motivated to misread the results food safety studies. Also, anti-GMO activists continue to insist that there is a conspiracy lead by large biotech companies.

McIntyre lays out the evidence that opposition to GMOs is a kind of science denial, and he concludes with a challenge: “If the folks who insist that GMOs are dangerous or unsafe no matter what the scientific evidence says are not denialists, is there any such thing as denialism at all?”

Listening to science deniers

McIntyre believes that conversations can help build trust, but you have to be careful not turn the conversation into an “us against them” argument. The discussion doesn’t need to be completely cold and rational: many science deniers will not be convinced by reeling off a set of unsupported facts. And it isn’t easy to rebut every scientific misperception. A more humble approach is better.

McIntyre points out a parallel between COVID denial and climate change denial. “For both the coronavirus and global warming, the denialist position has followed these steps:

McIntyre offers a set of “tools” to use in discussions with science deniers:

  1. Graphs, charts, and tables work.
  2. Emphasizing scientific consensus works.
  3. Personal engagement is powerful.
  4. Content rebuttal and technique rebuttal can be effective tools.

How do these work?

McIntyre’s conclusion: “The most effective way to talk to a science denier is to try to build trust through direct personal engagement, showing humility and respect, while demonstrating transparency and openness about how science works.”

Last modified: April 10, 2022
Dennis Mancl -

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