Roots of (scientific) denial
Science is the best way to dig out the truth of the natural world, but that doesn’t prevent many people from denying truths that are inconvenient or contrary to their preconceptions or faith.
In the last month, denial of global warming has subsided in the wake of a string of floods, droughts and heat waves, culminating in the “summer in March,” 2012. Although Americans’ attitudes toward warming ebb and flow, on April 17, a Yale University poll reported that 69 percent think global warming is affecting the weather in the United States.
In the same month, however, a Discovery Channel series called “Frozen Planet” attracted ire when scientists noted that it documented massive melting at the poles, but ignored the “why?” question. Scientists have said for decades that polar warming would be an early sign of global warming.
In the recent past, this phenomenon of “denialism” has also appeared in doubts about issues that have long been settled in the scientific community, such as whether:
HIV causes AIDS;
plants and animals evolve through natural selection;
vaccines prevent disease or cause autism;
refrigerant chemicals destroy the protective ozone layer; and even
whether smoking causes lung disease.
An April conference at the University of Wisconsin-Madison delved into the origin and development of denialism. Is a refusal to face facts growing more common? Are there better ways to explain how the world works?
Denial in the brain
Scientists, by training, are professional skeptics, but if after decades of debate 97 percent of them accept the link between greenhouse gases and global warming, why are so many unconvinced? “The theory is that if we tell people what we know, they will change,” says Arthur Lupia, a professor of political science at the University of Michigan, but that ignores how people really listen and make decisions.
Speaking to a high-level gathering of science journalists in Madison, Lupia said the problem does not reside with the audience. “The problem is us. Our expectations aren’t consistent with how humans react to information, what they will listen to, or what they will remember. People don’t pay attention, or they don’t remember what we said or what we intend them to remember.”
To change an opinion, you must first attract and then hold the audience’s attention, but attention wanders all the time. No matter how important you think your message is, Lupia says, “Biology does not change its rules … about when people will think about things that challenge them. … If I am saying something abstract, that does not connect to your core aspirations,” you may be more interested in counting tiles on the ceiling.
Can you hear me now?
To communicate with a general audience, Lupia says, “You have to make it close, concrete, immediate. I understand the joy of telling the whole story about climate, but there are some audiences that can’t handle it; in their reality, it’s not the most immediate thing. They might be more receptive if you make the conversation about pollution, energy security or energy costs.”
Information is filtered by attention and ideology, Lupia concludes. “Learning is always an away game. All the real action occurs in the audience’s heads,” he says.
Reasoning: Logical or “motivated”?
Ideally, science adheres to logical reasoning: the conclusion must be true if the premises are true.
Premise 1: “All dogs like to roll in dead fish.”
Premise 2: “Bert is a dog.”
Conclusion: “Bert likes to roll in dead fish.”
But psychologists say it’s common to see “motivated reasoning,” the tendency to fit new information into existing attitudes.
New information: The climate is warming.
Existing attitude: People are not changing the climate.
Conclusion: The change must be due to natural variation.
Making a judgment or decision can often involve a “fundamental tension between believing what you want and believing what you have to believe based on the information in front of you,” says Peter Ditto, professor of psychology and social behavior at the University of California-Irvine.
“There is overwhelming evidence” that hopes, fears and social connections affect our judgments, Ditto adds, “but it’s not just that we believe whatever we want. I want to be taller, but I don’t believe that because the data won’t let me.”
Since processing information and making judgments have major emotional components, the standards for evidence are skewed in favor of reinforcing our preconceptions. We are more skeptical about ideas that are new, or that conflict with our thoughts and opinions, Ditto contends.
Over the course of evolution, bad events — but not beneficial ones — forced our ancestors to focus on whether to fight or flee. “People are the same way about information,” says Ditto.
The social element in motivated reasoning surfaced in a 1950s experiment, when six people convinced a seventh, the only real subject, that two lines were equally long. One line was clearly shorter than the other, Ditto says, “But six of them are confederates, and a substantial number of [subjects] go with the obviously wrong answer. That’s the power of having other people who believe as you do. It’s much easier to believe something that does not comport with reality if a whole bunch of others” hold the same erroneous belief.
History of denialism
Although denial of global warming and the erroneous link between vaccines and autism both originated in the 1990s, the organized rejection of evolution dates to the 1920s, when some American Christian fundamentalists promoted creationism — a Biblical explanation for the diversity of life on Earth.
In a 2009 survey, 87 percent of scientists, but only 32 percent of all Americans, agreed that organisms have evolved over time through natural processes. Thirty-one percent of Americans thought humans and other living things “have existed in the present form since the beginning of time.”
Much of the attention to the issue comes from battles over teaching of evolution or creationism in public schools, but there is “a lot of misunderstanding,” about the anti-evolution movement in the United States, says Ronald Numbers, a professor of the history of science at the University of Wisconsin-Madison, and longtime student of the movement.
Although creationism is commonly considered a backlash against science, “Virtually nobody in the movement [in the 1920s] thought of themselves as anti-scientific,” Numbers says. “They were denying the scientific status of evolution.”
The dictionary defines science as “organized, certain knowledge about nature, and they said, ‘Nothing is certain about evolution, nobody has seen it.'”
During the 1970s, primarily in response to court decisions, creationism morphed into “creation science” or “scientific creationism,” Numbers says. “The anti-evolutionists realized that evolution had a great deal of scientific support … so their approach was that they, too, were scientific.”
Unlike most anti-evolutionists in the 1920s, the new creationists used a literal interpretation of the Bible to date creation to less than 10,000 years ago. But this created a problem, Numbers says, since according to the Bible, on the sixth day, “God created the animals and Adam named them all.”
No way Adam could rattle off the more than 1 million names of the modern species so quickly, but Numbers notes that the Bible refers to “kinds,” not “species.” If those “kinds” — created in Eden and saved on Noah’s ark — were equivalent to taxonomic families, they could have evolved into the profusion modern species.
“So creationists can accept evolution within the family, and all the evidence for speciation is welcome, because in only about 4,300 years since the flood, they have to have evolution of all the species,” says Numbers. “It’s evolution in fast-forward,” but only among closely related species.”
Even if “kind” equals family, anti-evolutionists exempt humans from this reasoning, allowing them to reject human descent from apes — our fellow hominids.
“It’s strange, I know,” says Numbers. “They are anti-evolution, but most of the evidence evolutionists use against them, they are happy to embrace! One thing that has not been true for 50 years, but lingers in the popular mind, is that creationists deny all forms of evolution.”
The manual of denialism?
Evolutionary biologists regard evolution through natural selection as the organizing principle of biology. Yet for 30 or 40 years, surveys have shown a substantial fraction of Americans, even a majority, who do not “believe in” evolution, Sean Carroll, vice-president for science education at the Howard Hughes Medical Institute, told the denial conference.
Carroll, who like many biologists is aghast at the effort to squeeze evolution into a biblical straitjacket, says, “The denial of evolution was my introduction to denialism.”
Typically, biologists have approached the evolution debate by amassing evidence, but “it’s never been about the data,” maintains Carroll, who is also a professor of genetics at the University of Wisconsin-Madison. “And if it’s not about the data, what are we talking about?”
An earlier example of denialism occurred in the 1950s, after Jonas Salk developed the polio vaccine, a breakthrough that halted a dreaded, paralyzing disease.
Many chiropractors, Carroll found, opposed vaccines since they negated the central premise of chiropractic — that all disease results from misalignment of the vertebrae. “It shocked me. They actively opposed, disputed the efficacy of the polio vaccine. The opposed the March of Dimes, and federal and state efforts to get everybody vaccinated.”
Five hallmarks of denialism
The opposition continued — even after the polio epidemic tapered off as a result of the mass vaccination that started in 1955, says Carroll. And he identifies the tactics used then as a “playbook” of science denial that is echoed in more recent struggles over evolution, vaccines and global warming:
1. Doubt the science:
- • “CDC statistics make clear that polio was disappearing anyway.”
- • “There is no real evidence that evolution is occurring; evolution is not science at all.”
2. Question the motivation:
- • “The vaccine manufacturers are just interested in profits.”
- • “Climate scientists are only interested in more grant money.”
3. Exaggerate normal scientific disputes:
- • Cite gadflies as authorities even though they are a tiny minority.
- • Insist on “balanced coverage” even when almost all of the experts are on one side of the issue.
4. Exaggerate the potential harm:
- • “We cannot control global warming without destroying our economy.”
- • “Darwin’s talk about the struggle for existence lead to the Nazi Holocaust and World War II.”
5. Appeal to personal freedom:
- • “Students should be able to opt out of classes on evolution.”
- • “We support each individual’s right to freedom of choice” on vaccines (American Chiropractic Association, 1998).
We just don’t agree!
Add it up, and the theme is this: The science must not be allowed to endanger a key philosophy, Carroll says.
But the cost of denialism is high, Carroll maintains. “It’s difficult, as an evolutionary biologist, to realize that half the county is deaf to anything you have to say, especially if the story you have to tell is about a magnificent achievement, understanding the complex relationship of living things on the planet, the deep history of our species.”
To reach young people, Howard Hughes has begun producing and giving away a series of videos on evolution called The making of the fittest.
The idea is to engage in storytelling — to help people understand and remember facts by putting them into a narrative framework, Carroll says. As a professor, he’s seen the power of a story. “When I got lost, off-topic, and students see me years later, they say they still remember some of those stories, and I know they don’t remember any of the genetics. Stories count.”
Time (dis)honored tactics
Naomi Oreskes, a professor of history and science studies at the University of California at San Diego, has written about the “merchants of doubt.”
The message, she says, is simple: The facts are not all in. We need to hold judgment until the scientists agree.
This kind of corrosive doubt — in the face of scientific certainty — is “very depressing” if you “believe that knowledge is power,” Oreskes says. “Knowledge is not powerful enough — an ideology is more powerful still. It’s about ideas, not facts.”
During the last half-century, she says, “Political powers are willing to attack rational truths, and those who deliver them.”
There is also money at stake in many of the issues, especially in the case of climate change, which threatens the fossil-fuel industry.
The model for such campaigns, Oreskes said, came from the tobacco industry in the 1960s. Facing growing evidence linking their profitable product to lung cancer, the industry settled on a strategy of promoting “Questions, manifested in a memorable maxim: “Doubt is our product.”
And for decades, doubt helped big tobacco deride and deny a tidal wave of evidence that cigarettes cause lung and heart disease.
The same strategy, Oreskes says, was adapted to undermine “nuclear winter” (the discovery that huge clouds of ash and dust released during nuclear war could freeze and starve the planet), the dangers of the insecticide DDT, acid rain caused by power-plant pollution, the ozone hole, and global warming.
The tactics were to “challenge the evidence, claim the science is not settled, cherry-pick the data, to demand balance from journalists and threaten to sue if they don’t,” says Oreskes.
Changing the climate change story
The basic physics of global warming have been known for 100 years, Oreskes said. Scientists started exploring the subject with early computerized climate models in the 1980s.
In 1992, Oreskes said, the first President George Bush, “Called for concrete action to protect the planet. We had political leadership that committed us to doing something, yet we never did take the concrete steps that Bush called for. It’s a story about political challenges, selling uncertainty, about science in the age of denial.”
The doubters, funded by the oil industry, included some prominent Cold-War physicists who had been advocates for Ronald Reagan’s anti-missile defense system. “They said the science was unsettled, that it would be premature to act,” says Oreskes, who was intrigued to find that one of those physicists, Frederick Seitz, had been a consultant to the R.J. Reynolds tobacco company.
In 1998, Seitz organized a petition against the Kyoto Protocol, the first international agreement to control greenhouse gases.
Seitz and his fellow doubters, Oreskes says, “Found a new enemy: environmental extremism. You see anxiety about environmentalists as socialists, using climate change as a lever to effect social or economic change.”
What began with a handful of people with roots in the Cold War has since spread to “a range of free-market think tanks, including the Cato Institute and the American Enterprise Institute,” Oreskes says.
The arguments against the settled scientific debate over warming, she adds, “are not just different interpretation of the data; that’s a normal part of scientific life. This is not about normal scientific claims. These are the scientific equivalent of saying Belgium invaded Germany during World War I.”
Why deny? Because it works, Oreskes implies. Almost 25 years after the scorching summer of 1988 brought global warming into the public sphere, the United States has yet to get serious about controlling greenhouse gases.
“We ignore the facts of nature at our peril,” says Oreskes. “Ignoring them is not going to make them go away.”
— David J. Tenenbaum
Terry Devitt, editor; S.V. Medaris, designer/illustrator; Molly Simis, project assistant; David J. Tenenbaum, feature writer; Amy Toburen, content development executive
- Recap. of the Science Writing in the Age of Denial conference ↩
- What is Motivated Reasoning? How Does It Work? Dan Kahan Answers ↩
- Basic concepts of logical reasoning ↩
- Extreme weather and climate events ↩
- AIDS denialism ↩
- Retracted autism study an ‘elaborate fraud,’ British journal finds ↩
- Resources for understanding evolution ↩
- Scientists Quantify Global Warming’s Threat to Public Health ↩
- Chiropractors v. Vaccination ↩
- Merchants of Doubt, by Naomi Oreskes and Erik M. Conway ↩