Last year, as the summer heat broke, a congregation of climate scientists and communicators gathered at the headquarters of the American Association for the Advancement of Science, a granite edifice erected in the heart of Washington, to wail over their collective futility.

Year by year, the evidence for human-caused global warming has grown more robust. Greenhouse gases load the air and sea. Temperatures rise. Downpours strengthen. Ice melts. Yet the American public seems, from cursory glances at headlines and polls, more divided than ever on the basic existence of climate change, in spite of scientists’ many, many warnings. Their message, the attendees fretted, simply wasn’t getting through.

This worry wasn’t just about climate change, but also stem cells. Genetically modified food. Vaccines. Nuclear power. And, of course, evolution: Challenging scientific reality seems to be an increasingly common feature of American life. Some researchers have gone so far as to accuse one political party, the Republicans, of making \”science denial\” a bedrock principle. The authority attributed to scientists for a century is crumbling.

It is a disturbing story. It is also, in many ways, a fairy tale. So says Dan M. Kahan, a law professor at Yale University who, over the past decade, has run an insurgent research campaign into how the public understands science. Through a magpie synthesis of psychology, risk perception, anthropology, political science, and communication research, leavened with heavy doses of empiricism and idol bashing, he has exposed the tribal biases that mediate our encounters with scientific knowledge. It’s a dynamic he calls cultural cognition.

Kahan rarely declines a speaking gig, and he came to the Washington meeting only to end up detonating the audience’s basic assumptions. First of all, he said, sitting on stage, thin, angular, his broom head of hair askew as always, there’s no credible evidence showing a decline in trust. Second, climate skeptics are convinced that scientists are on their side. They believe in science.

Their confusion, Kahan said, is a \”consequence of distrust of a different sort\”—fueled by cultural affiliation and fed by peers. What climate scientists have said didn’t create that confusion, so \”nothing they say is going to dissipate that.\”

The crowd grumbled and barked. During the Q&A, Gavin A. Schmidt, now director of NASA’s Goddard Institute for Space Studies, stood up. An editor of a leading science blog and TED talker, Schmidt is known for his public outreach.

This is a \”slightly nihilistic notion,\” he said to Kahan: that it \”doesn’t matter what you say, everything is determined by culture wars.\”

\”No, no,\” Kahan protested.

Granted, people have different backgrounds, Schmidt continued. \”But it isn’t the case that what we say makes no difference. That what we say has no difference. That’s patently not true.\”

Kahan slumped in his chair. That hadn’t been his point. Of course what scientists say matters. But they do not, as they imagine, whisper into the public’s ear. Scientists are so rigorous in their everyday work, yet when it comes to the public, those practices shrivel.

\”There are more things that are plausible for what’s going on than are true,\” Kahan pleaded. \”The only way to make progress is to use empirical methods to rip from the sea of the plausible the thing that actually matters. Otherwise we drown in storytelling.\”

For years, Kahan has sluiced that sea, pulling up inconvenient truths that expose the roots of scientific conflict. Far from a nihilist, he’s doing more than just showing off the problem. He’s trying to solve it.

Kahan inhabits an odd position: one of the best-known unknown academics in the country. Influential in criminal law, in recent years he’s become a vital bridge between the social and physical sciences, a lodestar in the science of science communication, a nascent field that tackles the gap between what scientists and the public know. He’s a public intellectual, his work closely followed by political elites, yet he remains a creature of draft papers, not TED talks. He practices what he preaches: Scientific communication is not about polish; it’s about process.

When it comes to the role of science in political debates, Kahan is no Pollyanna. While the public gladly accepts scientific advice on most topics—there’s no political debate about the public-health merits of pasteurization—a few issues, like climate change, have become polluted with cultural debris. This pollution defies education and intelligence, he’s shown; such smarts make people even more talented at rearranging facts to fit their views.

Like any good origin story, you could peg the start of cultural cognition to one point, more than a decade ago, when Kahan was struggling to understand debates over concealed-carry laws and their effects on gun violence. There was a deep divide among scholars and the public on how to interpret the evidence, and empirical research seemed unlikely to resolve the question. Something deeper was driving the public discussion.

At the time, two prominent models vied to explain how the public formed its opinions: One followed classical economics in assuming that the public was rational, weighing facts before drawing a conclusion; the other, from cognitive psychology, assumed irrationality, our minds riddled with biases that compromise our judgment. Neither seemed to describe the conflicts Kahan saw.

Then he met Donald Braman. At the time, Braman was an anthropology graduate student, and Kahan was a widely cited authority on criminal law. A lean marathoner, Kahan cut a distinctive path around Yale, zipping through campus on a scooter and walking his cat, Ann Richards, on a leash. (Richards remains a fixture in Kahan’s slides, and is known for surprising office guests from her cat tower.)

Braman pinged his ethnographic work to Kahan, who quickly responded: \”Do you want to collaborate?\” It’s a frequent question from Kahan, who ignores cant or status in favor of good, productive talk. He’ll host a post from a high-school science teacher on his blog, and one of his first questions to me, when conversation veered to the problems of science journalism, was: \”Do you want to write a guest post on it?\”

Braman also sent Kahan the work of Mary Douglas, an anthropologist who, several decades earlier, had developed a cultural theory of risk assessment. Social norms, above all else, informed how people judged risks, she said. The public divided along two spectra: one measuring their support of social structure, running from egalitarian to hierarchical; the other, their devotion to individualism or communitarianism. The scales combined for four essential \”worldviews.\”

Kahan looked past controversy over Douglas’s work—in particular, a 1982 book she co-wrote that attacked environmentalists (whom she saw as extremely egalitarian and communitarian, and motivated by contempt for industrial society)—and saw a powerful tool. He had already dipped into psychological research showing how we engage in \”motivated reasoning,\” shaping facts around our beliefs, especially in situations that threaten our identities. Perhaps the worldviews described by Douglas were shaping those biases and causing conflict? A believer in free markets might balk at climate change, given the predominant warming narrative aimed at curbing economic growth; an egalitarian-communitarian, meanwhile, would find the centralized authority demanded by nuclear power unbearable.

This sounded good to Kahan and Braman, who is now an associate professor of law at George Washington University, but these were stories. To get anywhere, they’d have to hold Douglas’s theories up against real-world measures. First, using responses from an existing survey that seemed to measure worldviews, they found that those views could explain a participant’s position on gun control more completely than any other fact, be it religion, fear of crime, geography, political ideology, or party. The hierarchs and individualists opposed gun control, while the egalitarians and communitarians supported it.

Senior legal scholars immediately objected, the start of a long line of smart people affronted by Kahan’s findings. Their protests boil down to a gut reaction: \”This couldn’t possibly apply to me!\” There are many exemplars of the genre, with The New York Times’s Paul Krugman providing an excellent case this year, skewing Kahan’s work to fit his belief that Democrats value science more than Republicans do. Few people can admit that they let their cultural values trump facts. Could you? \”We get a lot from our communities,\” Braman says. \”They help us think through problems.\” This was Douglas’s basic insight, and it explains why campaigners have spent decades arguing over cultural fault lines. The notion that truth can’t resolve a factual debate—it’s threatening.

Douglas, however, was also troubled, and evasive on what questions might elicit worldviews, a vagueness, Braman says, that also \”allowed her to apply the theory to whatever she wanted.\” Douglas (who died in 2007) told them she had not meant to describe fixed personality traits; to her, worldviews were fluid. At work, you may behave like a hierarchical individualist, but in your softball league, you may turn communitarian. The work is fine, she eventually told Kahan, but it’s not cultural theory as she intended it. They should get a new name.

Undeterred, Kahan and Braman held focus groups on divisive topics. Sparks from those yielded statements for their first original survey, which respondents rated for agreement: \”Society as a whole has become too soft and feminine.\” \”People should be able to rely on the government for help when they need it.\” The study showed that, in addition to guns and abortion, issues like nuclear power and global warming broke along worldview lines. Subsequent experiments would reaffirm that. Accepted scientific facts—that nuclear waste can be stored safely; that global warming is human-caused—were not reliably getting through those cultural filters.

This was in 2005, when a narrative had begun to form about a Republican war on science. A vast divide seemed to be opening up on topics like evolution, stem cells, and climate change. Kahan was the first to look at it diagnostically, says Edward W. Maibach, director of the Center for Climate Change Communication at George Mason University. This wasn’t just about the Republicans, and Kahan’s work moved the field away from blaming conservatives. \”It encouraged us,\” Maibach says, \”to look at our own practices as being the problem.\”

Many scientists continued unaware, however, content to dwell in the idea that if members of the public just got the right information, they would change their minds on climate change—the information-deficit model, as it’s called. As one researcher told me, geo­scientists have often thought \”like Englishmen talking to foreigners: The solution is to talk more slowly and more loudly.\” That began to change in 2009, when a batch of stolen emails from climate scientists gave contrarians a new outlet for criticism; misconstrued, the letters could make it seem that the researchers were being underhanded in how they handled their data. The backlash had begun.

That incident, in part, prompted the National Academy of Sciences to convene a symposium, in 2012, on the science of science communication. Kahan was a featured speaker. All the ideas you have about how the public understands science aren’t working, he told the audience, as leaders of the scientific establishment shifted uncomfortably behind him. It’s time to test your assumptions.

It was a bold talk, a coming-out moment.

Kahan is the son of scientists: his mother a microbiologist, his father a pharmaceutical chemist at Merck. Born near Harvard, he spent his first few years in New York City and then moved with his mother to Michigan’s Upper Peninsula, where he cultivated a love of skiing and a Midwestern practicality and openness. He read The Brethren, a book on the Supreme Court, and thought he’d really like to be a clerk. He was interested in how people, as a rule, knew what they knew— society, as he often says, isn’t \”sufficiently astonished by how amazing it is that people can recognize what’s known.\” Studying law provided one way to explore that.

At Harvard Law, he was known as a mild communitarian, a former classmate, Sheryll D. Cashin, told me. He got a reputation for his restless intellect, but most of all Cashin remembers his appeal during elections to the Law Review to cut down on \”chicanery.\” He cared about fairness, she says, and that, in a testosterone-saturated environment, helped him emerge as the consensus choice for president. Kahan had his choice of Supreme Court clerkships, and he joined Thurgood Marshall, drawn to his deep sense of justice. A proud moment for Kahan came in Marshall’s dissent in Payne v. Tennessee. By overturning a precedent on victim-impact statements with limited new evidence, he wrote, the court was making plain that its currency was not reason, but power. His office is decorated with Marshall photos, and he named his first child after the justice.

Kahan found his way, in 1993, to the University of Chicago, one star in a constellation of ambitious young law professors: Elena Kagan, Lawrence Lessig, Cass R. Sunstein, Tracey L. Meares, Anne-Marie Slaughter. The behavioral economist Richard H. Thaler was there, too, and the ferment was about undermining notions of rationality that drove Chicago’s traditional law-and-economics approach. The New Yorker even ran a story about the divide between \”old\” and \”new\” Chicago. Kahan, it noted, cast a write-in vote for Bernie Sanders in the 1996 presidential election, and had a bumper sticker in his office that read: \”SUBVERT THE DOMINANT PARADIGM.\”

The new faces at Chicago were interested in social norms and how they intersected with criminal law, particularly in their crime-plagued city. Kahan worked closely with Meares on how constitutional theory might better consider the rights of communities over individuals, like the desire of public-housing residents to let police search their buildings without a warrant in response to deadly gunfire, an idea that found the two scholars facing off against the ACLU—risky for untenured professors. Kahan also gained notoriety for his support of public shaming as an alternative punishment to prison for low-level crimes, and he was perplexed by the heated response he got: Why so much resistance?

But the neat boxes provided by the behavioral economists didn’t work for him. His work would go on to resist their excesses, their emphasis on irrationality, as much as it would reject the classic Chicago school. When people subvert facts to fit their worldviews, they are using reason. \”It’s not about too little rationality—it’s too much!\” Kahan says. Meares remains close to Kahan, and while she was surprised with how his work shifted, she sees his goals as fundamentally the same: \”It’s understanding how to give people a voice and how to get people to listen to each other.\”

Kahan left for Yale in 1999. Meares inherited his office, and he left behind two gifts: a Toy Story mousepad and his bumper sticker.

It’s not easy running Kahan down; letters disappear deep into his inbox, lost forever. Interview him at a conference, and the only free time involves following him to his hotel room as he tosses belongings into a worn roller bag. He’s often perched on his blog and Twitter account, and was an early adopter of digital preprints; many of his papers sit for years online before he publishes them. The reward of original thinking is endless demand: He has collaborations with Boston’s Museum of Science, the Nature Conservancy, the producers of the television show NOVA, the Annenberg Foundation, and Sencer, a science-education research group, among others.

\”The amount of work he does in a day is just embarrassing to the rest of us,\” Braman says. \”He doesn’t intend this, but it’s just brutally humiliating.\” Kahan wrote a book on the norm of reciprocity but lost interest and never published it. He has bouts of frustration when debating researchers who have not kept up with best statistical practices; if you should know better, he’ll let you know it. He still spends much time on the law: He built a Supreme Court clinic at Yale and teaches a course on evidence. He’s a restless teacher; student cartoons of Kahan feature a smoke puff zipping around a classroom.

Over the past few years, Kahan’s work has moved toward testing cultural cognition and its interplay with knowledge and psychological phenomena. Two of his recent studies have shown that numerically talented people are more likely to correctly evaluate evidence on whether to use something like a skin cream, but they’re also more likely to be polarized about climate change or gun control. It’s the curse of too much rationality. On encountering such a culturally contaminated topic, Kahan says, they open \”a confabulatory escape hatch from the trap that logic would otherwise be placing them in.\”

I saw evidence of that escape hatch earlier this year, when I finally persuaded Kahan to sit still for a day in New Haven. Wearing his standard navy-blue hoodie, Kahan was running through some new polling results with several graduate students in a law-school meeting room, the marble tiles of Yale’s Beinecke Library visible through the room’s stained-glass windows.

The survey data, which arrived the night before, seemed to show that people’s scientific knowledge had little to do with whether or not they accepted climate change. The public got the technical climate questions posed by Kahan right or wrong regardless of their values; four-fifths of the respondents most likely to be climate skeptics said the melting of Arctic sea ice would cause the ocean to rise. That’s wrong—otherwise we’d all worry about our cups overflowing when ice melts—but heartening in a way: These people knew that \”scientists say\” climate change contributes to a host of environmental risks, including rising sea levels.

But there was a catch. When Kahan went back to the more basic questions on climate change—the world is getting hotter, and that heating is caused by humans—his subjects shifted back into their polarized positions. They were not responding on the basis of the knowledge they had just demonstrated. Instead they were answering a far simpler question: \”What kind of person are you?\”

Some of the graduate students at the meeting had taken his new course, first offered last year, on the science of science communication. The course was meant as a call to arms. This is wide-open territory, he told them. The students are now fanning out to expand his work. One is studying journalism—a discipline not known for testing its methods—trying to tease out the line where a story goes from informing readers to kick-starting their biases. Another is looking at invoking curiosity, which might protect readers from motivated reasoning. Kahan will lead the course again this spring and is eager to teach it elsewhere.

As his collaborators spread out, they will encounter a world not always eager to embrace Kahan’s work. Some social scientists can\’t get past his ties to Mary Douglas; either they hold a grudge from her book or they echo her concern that worldviews don’t really exist in individuals. Others question the validity of cultural cognition in other countries, saying it reflects particular American values. Some seem to object to Kahan as an interloper. He’s \”an outsider to all those subdisciplines,\” says Matthew C. Nisbet, an associate professor of communications at Northeastern University. \”He doesn’t necessarily have an allegiance to one network or paradigm.\”

In particular, Kahan’s work doesn’t capture the political forces that may spur cultural cognition, says Robert J. Brulle, a sociology professor at Drexel University. What drives Congressional votes on climate? Not psychology. \”The best single predictor is the percent of electricity from coal in their district,\” Brulle says. Billions have gone into exploiting the psychological vulnerabilities Kahan has defined, by casting doubt on the science. If we had known how cultural cognition worked back in the 1980s, when warming came on the scene, could such campaigns have been rendered ineffective? Brulle doubts it. When huge economic factors are at play, that may be impossible, he says. \”You can’t expect a several-trillion-dollar industry to fold itself up.\”

Kahan concedes that point. People can be manipulated, and he’s not yet sure they can be protected against it. It’s frustrating for the many NGOs that come asking for his advice. \”He’s not going to come out and sell you an approach,\” Nisbet says. Kahan shares that frustration: \”I’m sick of showing reason being humiliated,\” he told me over breakfast in New Haven. He’s demonstrated the problem, so why run new studies showing different versions of it?

He’s taken some steps to test how his insights can be applied. Already influential is work he did on climate engineering, which found that when global warming was posed as a problem that could be solved through human ingenuity, not by limiting growth, hierarchical-individualists were more likely to support action. The implication: Meet people where they are. It’s not about changing their values, or changing Republicans to Democrats. \”The more pluralistic the solutions and technologies on the table to address a problem or a risk like climate change,\” Northeastern’s Nisbet says, \”the more likely people across the ideological spectrum are to accept those risks.\”

Kahan is also taking a new approach. For the past couple of years, he’s quietly assisted county planners in adapting to rising sea levels, testing how cultural cognition could prevent the climate debate from polluting their work. Perhaps he could prevent the need for escape hatches and let reason work. Not one for small ambitions, Kahan has done this in one of the most politically dysfunctional states of all: Florida.

Even before humans put our foot on the warming accelerator, the seas fought to reclaim Florida. Containing floods and storm surges there is like trash collection: something government is just supposed to do.

Six years ago, Florida’s southern counties thought it would help to coordinate their responses to the rising ocean. At the least, they should be working from common projections. So they proposed the Southeast Florida Regional Climate Change Compact, covering all the land from Palm Beach to Key West. It seemed a logical response. But the atmosphere shifted rapidly, as Republican skeptics like Rick Scott and Marco Rubio came to dominate Florida’s discussion of global warming. After a few years, a plan that would have extended some of the coordination to the three counties north of Palm Beach was undermined by furious crowds of Tea Party supporters swarming into public meetings. All three counties withdrew from the plan. There were concerns that Palm Beach, the most right-leaning county in the existing climate compact, might similarly abandon the project.

A couple of years ago, Kahan approached the compact, offering free help. (His work there has been supported by the Skoll Global Threats Fund, an NGO financed by a former president of eBay.) Kahan’s only condition was that, in the future, they’d package their findings about how to communicate effectively for other planners to use in a knowledge base he calls Grand Central. Until then he’d share little; Kahan doesn’t want to be the story. \”It’s just rude,\” he says. He respects the public too much. As a result, despite pleading on my part, what I can share about his Florida work is circumscribed.

Kahan does remember when he first met the compact’s collaborators. What should they do? they asked. \”You tell me,\” he replied. He’d share his research and ask them how it fit into their best practices. Then he’d take those ideas and test them, using focused surveys of county residents. With results in hand, officials would figure out how to convey the utter banality of planning for sea-level rise. They were not out to subvert the political process—there is no bigger believer in politics as the fundamental force in settling value differences than Kahan—but were just hoping that their research would get through if a curious citizen came across it. Of course, most wouldn’t.

Planners use the data Kahan has produced for them, says James F. Murley, executive director of the South Florida Regional Planning Council and senior adviser to the compact. They stay aware of values, and present their data free from partisan language and frames. \”We try to heed that, though it’s frustrating,\” he says. Murley thinks about it in terms of tribes. If tribes sniff a threat, \”they’re going to do what tribes do,\” he says. But \”there are ways to get around that and not trap yourself in that, by the language you use and the way you engage people.\”

The compact’s campaign, in the end, was not about messaging or finding magic words. Its communication strategy was its process. Through dozens of forums, Kahan says, many led by business and community leaders, the compact flooded Southeast Florida with exactly the information that ordinary people use to know what’s known to science: the example of people they trust using science to assist their decisions. And when a radio host, serving as a panel moderator, tried to inject tropes of the national climate debate into the meetings (\”What do Republicans in Washington have against science?\”), local leaders gently pointed out that three of the four counties have Republican mayors, or that 100 local businesses support the plans because they can see what’s happening. \”I don’t think it is about party,\” they’d say. \”I think it is about understanding what the problems are and fixing them.\”

All that normality paid off in April, when five county staffers stood before Palm Beach’s board of commissioners to testify in neutral language on the compact and its 110 mitigation and adaptation strategies for climate change: moving coastal roads, protecting freshwater supplies, fortifying fire stations. There were no protests, no Tea Party swarms. The council—five Democrats and two Republicans—voted unanimously to adopt the action plan. It was normal. Boring. Collecting the garbage.

Kahan plans to stick around in Florida even if his financing runs out—this is the luxury of holding an endowed chair. But he does seem to be straining against the limits of what one researcher can do. Braman, his longtime collaborator, thinks it’s absurd that Kahan is still a lone researcher. Ohio, Texas, Colorado, Minnesota have all invited him to help them and add that experience to Grand Central. \”They should just build an institute around him and staff him up with people,\” Braman says. \”And I’m kind of surprised that hasn’t happened.\” Kahan’s egalitarian mind-set can work against him. He’s not seeking status, Braman says. If he’s going to have that institute, someone must force it upon him.

For now, in Florida, dangers still loom. There’s a gubernatorial election this fall, and Tom Steyer, a billionaire pushing for climate action, has attacked Rick Scott with a fleet of ads, some based on climate change. The attacks were unlikely to invoke a pluralistic response to global warming. \”It probably won’t be great for our approach,\” Murley says. \”It’s probably going to make a mess.\” The tide of the national climate debate was rumbling in. Would they hold it back?