It has often been written on this blog and elsewhere that the mark of a true crank is hatred of the scientific consensus, be it consensus regarding the theory of evolution, the science that says homeopathy is impossible, anthropogenic global warming; various areas of science-based medicine; or the safety and efficacy of vaccines. Perhaps the most famous expression of distrust of a scientific consensus is the famous speech by Michael Crichton, in which he famously said:
Let’s be clear: the work of science has nothing whatever to do with consensus. Consensus is the business of politics. Science, on the contrary, requires only one investigator who happens to be right, which means that he or she has results that are verifiable by reference to the real world. In science consensus is irrelevant. What is relevant is reproducible results. The greatest scientists in history are great precisely because they broke with the consensus.
There is no such thing as consensus science. If it’s consensus, it isn’t science. If it’s science, it isn’t consensus. Period.
To which I (and many others) responded, “Bullshit! Period.”
In fact science is all about coming to a consensus, but it’s about coming to a consensus based on data, experimentation, and evidence, a consensus that has reproducible results that are, as Crichton put it, verifiable by reference to the real world. After all, what is a scientific theory like the theory of evolution or Einstein’s theory of relativity but a statement of the current scientific consensus regarding a major scientific topic? What is peer review but quality control (making sure the scientific methodology is sound) coupled with testing new science against the current consensus to see where it fits in or where it exposes weaknesses? What is science but attempting to forge a consensus regarding theories and statements that most accurately describe the universe in a useful and predictable way?
Of course, questioning the consensus is often necessary in science. Indeed, it is critical to scientific advancement. However, there is a huge difference between questioning a current consensus and producing the data and experimental evidence to show that there is a real scientific question and JAQing off about science. The latter, raising spurious or already answered questions about a scientific finding or theory one doesn’t like, belongs to the province of cranks and denialists, and it is what they are very good at. The problem is that they aren’t very good at realizing why their questions are not worthy of the attention that they think they are. A lovely example of this showed up on the Discovery Institute’s propaganda arm, its version of Age of Autism, so to speak, namely Evolution News and Views. In it, the Kent Heckenlively of the creationist set, the ever excitable Casey Luskin, penned a typical bit of silliness in which he asks the question, When Is it Appropriate to Challenge the “Consensus”?
If Casey had two neurons to rub together, he could answer the question in two sentences and echo how scientists would answer the question: When you have an actual scientifically valid reason, based on science, evidence, experimentation, and observational evidence, to think that the current scientific consensus about something is in error, then it is appropriate to challenge the scientific consensus. When you don’t, then it isn’t. Unfortunately, Casey doesn’t; so he can’t. Instead, we’re treated to a potpourri of pseudoscientific and denialist claptrap that was apparently based on an article in The American by Jay Richards entitled When to Doubt a Scientific ‘Consensus’. In the article, Richards postulates twelve “signs” that should lead one to doubt a scientific consensus, any scientific consensus (although he seems most concerned with anthropogenic global warming in this particular article, while Luskin is, of course, concerned mostly with “intelligent design” creationism versus the hated (by Luskin) “Darwinism.” There’s just one problem. Not a single one of these “signs” has anything to do with a scientific argument. Richards starts out with a reasonable enough introduction:
Anyone who has studied the history of science knows that scientists are not immune to the non-rational dynamics of the herd. Many false ideas enjoyed consensus opinion at one time. Indeed, the “power of the paradigm” often shapes the thinking of scientists so strongly that they become unable to accurately summarize, let alone evaluate, radical alternatives. Question the paradigm, and some respond with dogmatic fanaticism.
We shouldn’t, of course, forget the other side of the coin. There are always cranks and conspiracy theorists. No matter how well founded a scientific consensus, there’s someone somewhere–easily accessible online–that thinks it’s all hokum. Sometimes these folks turn out to be right. But often, they’re just cranks whose counsel is best disregarded.
So what’s a non-scientist citizen, without the time to study the scientific details, to do? How is the ordinary citizen to distinguish, as Andrew Coyne puts it, “between genuine authority and mere received wisdom? Conversely, how do we tell crankish imperviousness to evidence from legitimate skepticism?” Are we obligated to trust whatever we’re told is based on a scientific consensus unless we can study the science ourselves? When can you doubt a consensus? When should you doubt it?
Your best bet is to look at the process that produced, maintains, and communicates the ostensible consensus. I don’t know of any exhaustive list of signs of suspicion, but, using climate change as a test study, I propose this checklist as a rough-and-ready list of signs for when to consider doubting a scientific “consensus,” whatever the subject. One of these signs may be enough to give pause. If they start to pile up, then it’s wise to be suspicious.
So far, there isn’t much here to disagree with. Scientists are human beings; scientific fads come and go. Some scientific consensuses ultimately turn out to be wrong. Virtually all of them undergo significant revisions as new evidence comes in. Moreover, not all consensuses are created equal. Depending upon the field, the strength of any one scientific consensus can vary quite markedly compared to others, depending upon the science, the topic within that science, or even the subtopic within the topic. For example, the scientific consensus supporting the theory of evolution, particularly common descent, is exceedingly strong. Based on multiple lines of converging evidence from many different disciplines, evolution one of the strongest of all scientific consensuses. Similarly, the consensus that natural selection is one major driving force behind much of evolution is nearly as strong. However, as the discussion devolves into more detailed areas, inevitably the consensus weakens. Eventually, subsidiary areas of a discipline are reached where the consensus is weak or where there is no consensus. Often these questions are at the frontiers of the science and, because there is not yet a consensus, the most heavily researched and hotly contested areas of the science. Denialists often attack science at the very edges of a field as a proxy for attacking the much more strongly supported core theory. Creationists like Casey Luskin are actually notorious for this, jumping on new findings about, for example, “junk DNA,” whether it has a function, whether it is subject to natural selection, and, if so, how much, as a bit of logical prestidigitation to hide the fact that the core theory of evolution is supported by mountains of evidence and not in doubt by scientists.
It is also true that peer pressure and groupthink can make persuading scientists that a particular scientific consensus is in error can be a disturbingly slow and messy process at times. However, in the end eventually science does win out. One example (summarized very well by Kimball Atwood IV, MD) is the discovery that most duodenal ulcers are actually caused by a bacterium, H. pylori. Barry Marshall and Robin Warren first reported a curious finding of what they described as “unidentified curved bacilli on gastric epithelium in active chronic gastritis” (not ulcer) in two letters to The Lancet, published on June 4, 1983. They reported that it wasn’t seen using traditional staining methods and suggested that they might be associated with gastritis. By 1992, multiple studies had been published establishing the causative role of H. pylori in peptic ulcer disease, and medical practice rapidly changed. That’s less than ten years, which, given how long it takes to organize and carry out clinical trials, is amazingly fast. Yet somehow a favorite denialist myth is that “dogmatic,” “close-minded” scientists refused to accept Marshall and Warren’s findings. It’s an example of a scientific consensus that deserved to be questioned, was questioned in the right way, and was overthrown.
In other words, it was nothing like Richard’s twelve “signs”:
- When different claims get bundled together.
- When ad hominem attacks against dissenters predominate.
- When scientists are pressured to toe the party line.
- When publishing and peer review in the discipline is cliquish.
- When dissenting opinions are excluded from the relevant peer-reviewed literature not because of weak evidence or bad arguments but as part of a strategy to marginalize dissent.
- When the actual peer-reviewed literature is misrepresented.
- When consensus is declared hurriedly or before it even exists.
- When the subject matter seems, by its nature, to resist consensus.
- When “scientists say” or “science says” is a common locution.
- When it is being used to justify dramatic political or economic policies.
- When the “consensus” is maintained by an army of water-carrying journalists who defend it with uncritical and partisan zeal, and seem intent on helping certain scientists with their messaging rather than reporting on the field as objectively as possible.
- When we keep being told that there’s a scientific consensus.
Oddly enough, most, if not all, of these warning signs apply to denialists and cranks. Richards appears to be engaging in a massive case of projection. I’m not going to examine each of the twelve “signs” in detail (that will be left as an exercise for the interested reader), but I will examine a few of the most egregious “signs.” For example, when it comes to ad hominem attacks, Richards writes:
Personal attacks are common in any dispute simply because we’re human. It’s easier to insult than to the follow the thread of an argument. And just because someone makes an ad hominem argument, it doesn’t mean that their conclusion is wrong. But when the personal attacks are the first out of the gate, and when they seem to be growing in intensity and frequency, don your skeptic’s cap and look more closely at the evidence.
Crank movements, of course, excel at the ad hominem attack. Creationists like Casey Luskin, for instance, spit the term “Darwinist” at evolutionary biologists and frequently try to link evolution (and thus its defenders) Nazi-ism and the Holocaust, eugenics, social Darwinism, and all manner of evils. Above all, evolutionists must be atheists, which to many creationists is the worst thing a person can be, given the vehemence of the invective.
Speaking of invective, one crank in particular, J.B. Handley has made a special study of seeing just how nasty his attacks can be. Generation Rescue and its propaganda arm Age of Autism specialize in “venomous invective,” particularly against Paul Offit and anyone else who opposes its anti-vaccine agenda. After all, this is the same man who launched personal attacks on Steve Novella that can only be viewed as more than venomous. This is the same man whose misogynistic attacks on Amy Wallace, a journalist who wrote an excellent article on the anti-vaccine movement, made him infamous throughout the science-based blogosphere. This the same man whose blog posted a Photoshopped picture of Steve Novella, Amy Wallace, Paul Offit, and Trine Tsouderos sitting around the table for a Thanksgiving feast, the main course of which was a baby.
If we look at the “case study” used by Richards, AGW denialists also excel at the same tactics, painting scientists as hopelessly politically motivated, corrupt, and lying. They hack e-mails looking for dirt and try to embarrass scientists by posting them. They attack Al Gore, as the most famous advocate of political action to mitigate the effects of AGW as fat, stupid, and corrupt. The list goes on.
By Richards’ criteria, the vaccine, evolution and AGW denialists send up huge red flags, as a major compoenent of their message consists of ad hominem attacks on scientists. As for “misrepresenting the actual peer-reviewed scientific literature,” what is The Discovery Institute, Age of Autism, NaturalNews.com, and every other denialist website or blog but veritable fonts of misrepresenting scientific literature? Hardly a week goes by, it seems, that I’m not applying a bit of the ol’ not-so-Respectful Insolence to some bit of nonsense or other about a scientific study laid down by the anti-vaccine movement or some quack or other. Back in the day, I used to do the same thing more often with creationist misrepresentations of science, but for whatever reason I don’t do that as much anymore. Perhaps I should.
It’s also hard not to note a distinct feeling of repetition in Richards’ list. For example “When ‘scientists say’ or ‘science says’ is a common locution” and “When we keep being told that there’s a scientific consensus” are more or less the same thing. Perhaps the silliest part of this whine is this:
A scientific consensus should be based on scientific evidence. But a consensus is not itself the evidence. And with really well-established scientific theories, you never hear about consensus. No one talks about the consensus that the planets orbit the sun, that the hydrogen molecule is lighter than the oxygen molecule, that salt is sodium chloride, that light travels about 186,000 miles per second in a vacuum, that bacteria sometimes cause illness, or that blood carries oxygen to our organs. The very fact that we hear so much about a consensus on catastrophic, human-induced climate change is perhaps enough by itself to justify suspicion.
Now there’s some flaming stupid strong enough to increase the planet’s temperature by at least 1° C, if not more.
Richards apparently doeesn’t know the difference between scientific theory and scientific fact. That salt is sodium chloride is a fact. That light travels 186,000 miles per second in a vacuum is a measurement and a fact. That blood carries oxygen to our organs is a fact. Of course, no one argues about them; they are well-settled facts, not theories. They are trivially obvious. Arguing about them would be as trivial as arguing about what I had for breakfast this morning or whether the above paragraph by Richards represents the essence of scientific ignorance. A theory is a higher level construct supported by facts, experimentation, and evidence.
Casey Luskin’s and Jay Richard’s tag-team of flaming stupid demonstrate a profound ignorance of science–even an anti-scientific bent. They don’t like science because it either doesn’t support their political beliefs (Jay Richards and AGW) or their religious beliefs (Casey Luskin and evolution). Sure, scientists can at times be as petty as any human being. They are as prone to groupthink and ideology as any group of people can be. But the wonderful thing about being a scientist is that science is a process. Although it is an activity of people it does not depend on any group of people. Eventually, even when scientists go down wrong alleys or succumb to fads, science wins out. It is self-correcting. The process may not be as fast as we like. It may not be as linear as we like. In fact, sometimes it’s damned messy and frustrating. However, it is the best process we have for finding out how our universe works.
Oh, and for building a consensus about how the universe works. It’s perfectly acceptable to challenge such a consensus, but if you don’t have the goods in the form of evidence, experimentation, and data to show that the consensus is in serious error, there is no reason for scientists to take your challenge seriously.
ADDENDUM: Joshua Rosenau has an excellent takedown of this combined idiocy as well. Key passage:
But moving past those trivialities, Casey and Jay’s underlying point is catastrophically wrong. As John Ziman points out in Reliable Knowledge: “the goal of science is a consensus of rational opinion over the widest possible field” (emphasis original). The beauty of science is precisely that it is rooted in our shared reality, and as such it is subject to the formation of consensus on which new work can build.
Yep, that’s about right. I’ll ask again: What is a scientific theory but a scientific consensus about how one aspect of how the world works?