The longer I’m in this whole science-based medicine thing, not to mention the whole skepticism thing, the more I realize that no form of science is immune to woo. To move away from medicine just for a moment, even though I lament just how many people do not accept evolution, for example, I can somewhat understand it. Although the basics of the science and evidence support the theory of evolution as the central organizing principle of all biology, much of the evidence is not readily apparent to those who don’t make it a calling to study biology, evolution, and speciation. It’s not like, for example, gravity, which everyone experiences and of which everyone has a “gut level” understanding. So, not unexpectedly, when the theory of evolution conflicts with a person’s religious beliefs, for most people it’s very easy to discount the massive quantities of evidence that undergird the theory of evolution. It’s not so easy to discount the evidence for gravity.
In many ways, medicine is similar to evolution, but the situation is possibly even worse. The reason is that much of the evidence in medicine is conflicting and not readily apparent to the average person. There’s more than that, though, in that there are a number of confounding factors that make it very easy to come to the wrong conclusion in medicine, particularly when looking at single cases. Placebo effects and regression to the mean, for example, can make it appear to individual patients that, for example, water (i.e., what the quackery that is homeopathy is) or placebo interventions (i.e., acupuncture) cures or improves various medical conditions. Add to that confirmation bias, the normal human cognitive quirk whereby all of us — and I do mean all of us — tend to remember information that reinforces our preexisting beliefs and to forget information that would tend to refute those beliefs — and, at the level of a single person or even practitioner, it’s very, very easy to be misled in medicine into thinking that quackery works. On the other hand, at the single patient/practitioner level, one can also see evidence of the efficacy of modern medicine; for example, when a person catches pneumonia, is treated with antibiotics, and recovers quickly. Regardless of whether they’re being used to demonstrate quackery or scientific medicine, because personal experience and the evidence that people observe at the level of the people they know can be very deceptive in medicine, science-based medicine, with its basic science underpinnings and clinical trial evidence, is necessary to try to tease out what actually works and what doesn’t.
Medicine does, however, have its version of a theory of evolution, at least in terms of how well-supported and integrated into the very fabric of medicine it is. That theory is the germ theory of disease, which, just as evolution is the organizing principle of biology, functions as the organizing principle of infectious disease in medicine. When I first became interested in skepticism and medical pseudoscience and quackery, I couldn’t envision how anyone could deny the germ theory of disease. It just didn’t compute to me, given how copious the evidence in favor of this particular theory is. It turns out that I was wrong about that, too.
On Friday there was a video released that provides a very clear, succinct explanation of germ theory denialism: