Those of us involved in journalism, education and science like to believe that facts and science illuminate the way through contentious debates. We believe that given ample evidence, thoroughly weighed, we will arrive at some consensus. At the very least, our viewpoints will converge. This devotion to objective facts, the scientific method and the primacy of evidence is the basis for a liberal democracy.

Oh, how very 18th century.

According to Yale professor of law and psychology Dan Kahan in a paper published last year in the journal Nature Climate Change, with greater knowledge of science and ability in rational reasoning, people don’t reach consensus. Indeed, on topics with political overtones, such as global warming, people become more polarized with greater science literacy.

If people disagree with scientists, Kahan and his co-authors state, it’s not necessarily because they lack knowledge, or even that they take intellectual shortcuts to come to their opinions. If that were true, on an issue such as global warming, about which scientists have a great deal of consensus, we’d expect citizens to come to agreement as their knowledge of the issue increases.

Quite the contrary, says the study, which looked at a broadly representative sample of more than 1,500 people and their attitudes toward global warming and nuclear power.

Political conservatives were found to form opinions consistent with an individualistic and hierarchical outlook. The more liberal respondents tended to adopt opinions that support an egalitarian and communitarian framework. This means conservatives will tend to dismiss global warming because to show concern would invite the possibility that we — individuals — aren’t up to the task of preventing it. Likewise, a liberal with distrust of big business is inclined to oppose genetically modified organisms, not necessarily because of evidence, but because GMOs are often developed and sold by big corporations, which are seen as incongruent with egalitarian and communitarian mindset.

Eventually, to act effectively, collectively and decisively, we will need to overcome self-interested reasoning that ignores evidence. Real progress against global warming will require concerted, science-based public action.

As Kahan noted in a follow-up paper, “liberals and conservatives were uniformly prone to ideologically motivated reasoning.” Consciously or unconsciously, we parse evidence to reinforce our views and the views of the groups with which we identify. And the more sophisticated we are, the better we are at it.

This news, of course, is distressing to those of us who thought we lived in an evidence-based world. Turns out, as I write an article — this Voices piece, for example — I can expect a sliver of readers to accept what I write as engaging and informative, and thoughtfully examine the arguments within. But huge chunks of readers on the “right” and “left” (to keep this simple) will reject my arguments and question my motives — not on the basis of evidence or lousy writing, but because they don’t see me as one of them.

In fact, Kahan raises the possibility that communicating science in a politicized environment will only serve to further polarize. If that’s the case, does it make any sense at all to communicate about science as a scientist, teacher or journalist — especially about supercharged topics such as global warming?

I believe it does.

Science and the pursuit of knowledge are terrific stories to tell — stories that shed light on human nature and the nature of the world. They are too good and too interesting in their nuance and complications to leave to the black-and-white world of activists and propagandists. And they are important for creating the critical agreement needed for collective decision making.

We can muddle along without such a foundation for a while. Whether or not we agree that humans have changed the climate, farmers will plant the crops they need to stay in business, and leaders in coastal cities will make real changes to address rising sea levels. Some measure of skepticism and discord can even have a benefit — by forcing thorough examination of an issue before the body politic acts too hastily.

But eventually, to act effectively, collectively and decisively, we will need to overcome self-interested reasoning that ignores evidence. Real progress against global warming will require concerted, science-based public action.

As communicators, we can frame issues in ways that let people see them in a new light that is less threatening to their political predisposition.

Is there hope? Yes. History offers numerous examples in which attitudes eventually change in the face of evidence — especially as that evidence is presented and understood in a new way. Take the slow but steady decline in the number of U.S. residents who smoke and the acceptance of gays and lesbians. In both cases change was accomplished only in part by presenting the “facts” — that smoking causes cancer and heart disease, that homosexuality has little to do with upbringing or choice. Instead, change came more indirectly. Smoking came to be seen as “uncool,” and interventions such as indoor smoking bans and higher taxes made it harder to start, easier to quit and more difficult to continue. Homosexuality came to be seen less as a matter of morality and more as a civil rights issue, even as a libertarian cause. As these issues were framed differently in public discussion, people were able to navigate to a new opinion without contradicting other strongly held beliefs or violating the norms of their social group that Kahan showed can so firmly attach us to scientifically nonviable positions.

What does this mean for an issue such as global warming? We need to dislodge the issue from the burden of its cultural baggage — as Kahan says, “[clean] up that environment once it has been contaminated with polarizing meanings.” And that’s where the scientists, teachers and journalists come in. As communicators, we can frame issues in ways that let people see them in a new light that is less threatening to their political predisposition. For example, we can discuss a move away from coal power plants in terms of the public health threats of emissions rather than climate change. And we can portray carbon taxes as a way to reduce the tax burden elsewhere while reducing the conflicts of land use and pollution associated with fracking for gas, drilling for oil and slicing off mountaintops for coal. In both cases, the climate would benefit even though it’s not the primary motivation for change.

Yes, it may take a long time to turn this ship around, but I’m optimistic that it will turn. As they say, facts are stubborn things. We humans tell stories and make arguments, and eventually the truest of them — whether it’s a sun-centric solar system or a round earth or evolution or anthropogenic climate change — becomes the one we all tell. View Ensia homepage