The AP stylebook, bible to journalists everywhere, has made an official ruling on the perpetually vexing question of what to call that hardy band of (mainly older, white, conservative, American) folks who reject the findings of mainstream climate science.

For a long time they were called "skeptics," but eventually that started to irritate climate scientists. Science is, after all, just operational skepticism. But when one retains skepticism long after it is warranted, one is no longer a skeptic, one is in denial.

So then "denier" became the term of art among the more sharp-elbowed climate hawks. But that irritated climate deniers, who claimed that the term is meant to associate them with Holocaust deniers, and if climate deniers hate anything, it's unfair comparisons with Nazis or mass murderers.

AP, in its Solomonic wisdom, has elected to eschew both terms. Instead it's going with "climate change doubter," or alternatively, "those who reject mainstream climate science," which trips right off the tongue.

Predictably, this pleased no one, as the replies under this tweet illustrate:

AP Style tip: For those who don’t accept climate science or dispute world is warming from man-made forces, use climate change doubters. — AP Stylebook (@APStylebook) September 22, 2015

My hot take: It doesn't really matter. Nothing of particular consequence rests on what journalists choose to call these people. Certainly nothing that would justify the endless hours of debate that have been devoted to it.

Personally, I like the term "climate truthers," which better captures the flavor of the thing. It's not like "those who reject mainstream climate science" all have the same story about why they reject it. There are dozens of varieties of counter-theories, as many as there are theories about Kennedy's assassination. What unites them all is a conviction that the official story can't be right, that it's covering for a nefarious agenda, that the truth is out there.

But really, use whatever term you want. All the huffing and puffing and language policing is tiresome.

What is important is properly comprehending the phenomenon itself. And key to that is understanding that it's not primarily about climate science at all, but about tribal affiliations, reinforced through a process called motivated reasoning.

Conclusions are usually the beginning, not the end, of human reasoning

The popular conception of reason is that it poses a question, gathers evidence, weighs the evidence, and draws a conclusion. But that turns out to be a highly idealized conception, tracing back to positivism and the Enlightenment.

In fact, human beings are not primarily rational creatures. We are primarily social creatures. We are born into specific social contexts, overlapping tribes from which we absorb our worldviews and values. We stitch our identities together out of those tribal affiliations. Most of what we believe, we do not conclude. We do not reason to it at all. We inherit it.

Those inherited beliefs are often tribal markers, conditions of approbation, even acceptance, among our tribes. Because belonging to tribes is fundamental to our well-being, those markers become very important to us. Protecting them is adaptive behavior, among our most basic instincts.

And protect them we do, via what social scientist Dan Kahan calls "identity-protective cognition." (Ezra Klein wrote about it here.) We are primed to resist information that casts doubt on our core beliefs and values. Such resistance is deeply rooted, often operating at a level beneath conscious awareness.

So reasoning in the real world is usually the opposite of the idealized conception. Rather than ask questions and reason to conclusions, what most of us do, most of the time, is begin with conclusions and reason to justifications. We use our cognitive powers to build a case for what we are already inclined, for reasons of tribal affiliation, to believe. To use the analogy favored by psychologist Jonathan Haidt (via Chris Mooney), we think we're being scientists, but we're actually being lawyers.

That's motivated reasoning. It's not a flaw, a weakness, or an exception. It's likely what cognition is for. After all, why would evolution select for a species of pure reasoning machines? Beyond our ability to successfully navigate our immediate surroundings, we don't really need accurate information, certainly not at the level of basic worldviews. It doesn't have a ton of adaptive value.

What does have adaptive value is our ability to access the benefits of community, to enter into reciprocal relationships with others around us for mutual benefit. That's what evolutionary pressures are likely to select for — the master to which reasoning is a servant.

This is not to say that inquiry is futile. It is possible to make self-criticism and self-correction themselves tribal values, to encourage the cognitive effort (and cushion the social risk) of skepticism. It is possible for individuals to develop, through practice, the mental habits of self-analysis and openness to revision. And science itself is, of course, an attempt to formalize those mental habits and be rigorous in their use. But it's difficult to reason that way, exhausting both intellectually and psychologically, so most people, most times, don't.

Now, motivated reasoning is strikingly easy to recognize ... in other people, who disagree with you. It is much more difficult to recognize when you and your cohort do it. But all tribes are guilty of it.

Nonetheless, it's facile to conclude that "everyone does it" and leave it there. Some tribes and individuals are more prone to it than others, and in varying amounts on different issues and in different circumstances.

Climate denialism is identity protection on the American right

Which brings us back to the climate truthers. What's happened is that rejection of mainstream climate science has become a powerful tribal marker in the US conservative movement.

And it is mostly the US conservative movement. As Jonathan Chait pointed out in his recent piece, there are smatterings of similar science rejection in Australia and in European splinter parties, but nowhere else in the developed world has climate, er, doubt taken over a major political party. It is, as he says, "a regional quirk in the most powerful country on Earth."

The question of how exactly the truthers' disposition toward climate science might best be described — skepticism, doubt, paranoid hostility, whatever — is beside the point; what's going on has little to do with how they assess climate science. The story of climate trutherism is not primarily about science at all, or even about climate change. It is part of something much larger, a story of how the US right became radicalized, aggrieved, empowered, and epistemically insular. It is the story of asymmetrical polarization, which, as I've said before, is key to understanding American politics.

I am fond of this quote from Rush Limbaugh:

We really live, folks, in two worlds. There are two worlds. We live in two universes. One universe is a lie. One universe is an entire lie. Everything run, dominated, and controlled by the left here and around the world is a lie. The other universe is where we are, and that’s where reality reigns supreme and we deal with it. And seldom do these two universes ever overlap. … The Four Corners of Deceit: Government, academia, science, and media. Those institutions are now corrupt and exist by virtue of deceit. That’s how they promulgate themselves; it is how they prosper.

Government, academia, science, and media lie. Only the US conservative movement sees the truth.

That kind of embattled, conspiratorial thinking is common among splinter parties and disaffected factions everywhere, especially among demographics in the process of losing their previous position of privilege. The unique dilemma and dysfunction of US politics is that such thinking, with all its attendant nativism, racism, authoritarianism, and aggrieved entitlement, has almost entirely taken over one of the country's two major parties.

The question of what to call climate truthers is only one small (and, honestly, not particularly significant) piece of a much larger puzzle, which is how media and political institutions built for symmetry grapple with an era of asymmetrical polarization.