On this long Labor Day weekend in the US, we're bringing you a set of opinion pieces from various Ars writers—and we'd love to have you join the conversation in the comments.

"To be clear. I believe in evolution and trust scientists on global warming. Call me crazy." With that tweet, Jon Huntsman set himself apart from every other candidate in the Republican primary field. Despite his phrasing, Huntsman, who is barely registering in most polls, was clearly hoping that the public would believe most other candidates to be a bit loopy by contrast.

Agreeing with the scientific community has become a key issue in recent presidential campaigns. Evolution came up at a debate during the previous Republican primary season, and Rick Perry, the current front runner, was put on the spot about it at a recent campaign event (he flubbed his answer on several levels). And, as Huntsman's tweet suggests, the reality of climate change has been a hot topic.

How did science become such a prominent political football? It really hasn't. The candidates' responses to questions on scientific information have become a proxy for other things, and people across the political spectrum are listening to what those responses say about the candidates' way of thinking.

It's not what you know, it's who you listen to

The basic principles of natural selection are pretty easy to understand. So are the rough outlines of how the greenhouse effect operates. If a candidate evaluates that information, I'd certainly hope they'd come to the same basic conclusions that most of the scientific community has. That said, I'd certainly forgive a presidential candidate if he or she didn't know them; it's not generally what we elect presidents to know. The same is true for many things, such as the economics of offshore wind power. We elect people in part because of the general shape of their policies, and in part because we hope that, should they be called upon to know these things, they will find the most reliable sources of information and listen to them.

Questions about evolution work in this manner on multiple levels. Obviously, on a scientific level, the evidence for evolution is extremely compelling. If you would rather defer to expertise than study it yourself, every scientific society out there that has voiced an opinion on evolution has supported the science and its place in the biology classroom. Finally, the US court system has determined that creationism and its milder cousin, intelligent design, are inherently religious and therefore cannot be taught as "science" in the public school system.

All of which make the actions of Michelle Bachmann and Rick Santorum, who have continued to promote the teaching of intelligent design, a bit odd. But those actions pale in comparison to Rick Perry, who not only thinks there are problems with evolution and that creationism should be taught in schools, but actually thinks the schools in his own state are actually doing so.

On the climate side, a number of the candidates have never accepted the expertise of groups like the National Academies of Science; a few others have done so (Gingrich and Pawlenty have both supported policies to limit CO 2 emissions) but have since disowned that position. Mitt Romney is no longer sure that the planet is warming at all. And Rick Perry has once more staked out the most extreme position, saying that it's all just a fraudulent attempt to get grant money. "I think there are a substantial number of scientists who have manipulated data so that they will have dollars rolling into their projects," he has said. "And I think we are seeing almost weekly, or even daily, scientists are coming forward and questioning the original idea that man-made global warming is what is causing the climate to change."

Actually, the consensus about anthropogenic climate change doesn't appear to be changing; the argument that scientists are in it for the money is transparently bogus.

So, what have we learned from this? With the exception of Huntsman, the candidates don't know science, haven't bothered to ask someone who does, and, in several cases, don't even know anything about the settled policy issues (judicial precedent and investigation of claims about fraud). Why would we want these traits in a president?

Actually, some people do

However, the fact is that Huntsman is barely registering in most polls, and the leading candidates in the Republican party are successful in part precisely because they are voicing an opinion that runs counter to expertise. For many in the US, expertise has taken on a negative cultural value; experts are part of an elite that thinks it knows better than the average citizen. (This is accurate, for what it's worth.) Very few object to that sort of expertise when it comes time to, say, put the space shuttle into orbit, but expertise can become a problem when the experts have reached a consensus that runs against cultural values.

And, for many in our society, scientific expertise has done just that. Abstinence-only sex education has been largely ineffective. Carbon emissions are creating a risk of climate change. Humanity originated via an evolutionary process. All of these findings have threatened various aspects of people's cultural identity. By rejecting both the science and the expertise behind it, candidates can essentially send a signal that says, "I'm one of you, and I'm with you where it counts."

This is not some purely partisan phenomenon. On other issues, rejection of scientific information tends to be associated with the political left—the need for animal research and the safety of genetically modified foods spring to mind. These positions, however, are anything but mainstream within the Democratic Party, so candidates have not felt compelled to pander to (or even discuss) them, in most cases. That's created an awkward asymmetry, one where a single party has a monopoly on public rejection of scientific information and certain kinds expertise.

For Jon Huntsman, that's a problem. In an ABC News interview, he argued that the leading candidates' stance would make them unelectable. "The minute that the Republican Party becomes the party—the anti-science party—we have a huge problem. We lose a whole lot of people who would otherwise allow us to win the election in 2012. When we take a position that isn't willing to embrace evolution, when we take a position that basically runs counter to what 98 of 100 climate scientists have said, what the National Academy of Science—Sciences has said about what is causing climate change and man's contribution to it, I think we find ourselves on the wrong side of science, and, therefore, in a losing position."

It's a reasonable concern. Personally, I wouldn't vote for a candidate who rejects science and expertise, and as a voter, I'd like to have a viable choice between two qualified candidates. At the moment, it's looking like I won't.

My biggest concern is that, ultimately, Huntsman may be wrong. We're in an environment where economic concerns will almost certainly dominate the election. And the campaigns will be covered by a press that cares more about the strategy of what a candidate said than its accuracy, a press that thinks it achieves balance by pretending there are two sides on every issue that merit serious consideration. In that environment, it's entirely possible that the US electorate may not recognize or care much about the implications of a few scientific questions.

Besides, a candidate who rejects science can apparently use that position to attract the support of somewhere above a quarter of the electorate. That's not a bad start for a presidential campaign.