Source: J. Krueger

Science is the great antidote to the poison of enthusiasm and . ~ Adam Smith

I have picked on, criticized, derided, or deonconstructed many a claim that, though popular, does not meet minimum standards of credible evidence or rationality. Many of these claims call for certain kinds of belief (be it in the paranormal, the esoteric, the mystical, or simply the improbable or the impossible). It’s been fun to do this work, but it has also been frustrating because there will never be an end to human gullibility, wishful thinking, and hopeful belief. Because of that, there will always be providers and enablers. At the same time, the scientific enterprise is fraught with crises of theory or of method, scandals, , and incompetence. It is easy to point to any one of these failures and to (illogically) conclude that one might as well believe anything as long as it sounds good and feels good.

In our regular college teaching – and I am speaking here for my colleagues and myself – we see our mission to not only convey content but also to train our students in critical thinking. As the content changes and grows, critical thinking skills will always be needed to distinguish the credible from the incredible. This may sound like a cliché but I repeat it cheerfully. In fact, in my limited experience with the students I teach at my university, I find that their focus on content seems to have grown stronger and fiercer over the years. They want to learn “stuff.” I suspect that the culture of cramming and testing and forgetting, which pervades the American educational system, is to blame for this. Where are the tests of critical thinking? Where are the tests of and design? Such tests are too hard to write and score and they don’t have a bottom line of “stuff” that you can take home (if it stays with you long enough before forgetting sets in).

Besides laziness and undeveloped critical thinking skills, a misplaced sense of tact contributes to the survival and spread of bad ideas. Many people regard personal beliefs as sacred possessions that must not be challenged. I am burning to see a confrontation between two conspiracy theorists, one who believes that the footage of Armstrong’s moon landing was a fake and another who believes that Apollo 20 brought back the remains of aliens from the dark side of the moon. I am clinging to the thought that these two would have to disagree with each other and that each would have to try to win the other over to her type of conspiracy theory. In my darker moments, however, I wonder if they would rather accept both types, concluding that the moon exploration that NASA told us about did not happen, but that other trips, which they do not tell us about, did happen.

Polite society demands that we do not challenge a person’s beliefs if these beliefs are held strongly or if there is no immediate and evident harm in them. This kind of tolerance sounds enlightened because it is after all a tolerance and tolerance is good. But is it tolerance misunderstood? In many posts (e.g.), I have expressed my skepticism about religious belief. To me, these efforts were a matter of intellectual duty and objection. At the same time, I (hope I) have not attacked individual people or questioned their right to practice their religion. These are different things, and I hope the line between them is clear.

In today’s post, I would like to call your to an article by Lawton Swan and colleagues (2015), which appeared in Professional Psychology: Resarch and Practice. Swan et al. assert that “psychologists should reject complementary and .” In its unadorned bluntness, this assertion is jarring and a violation of the conventional sense of tolerance. It is also surprising given the cliché that one (i.e., science) cannot prove a negative. And here it gets interesting. How can Swan demand the dismissal of a whole class of practices, for which there may exist at least some positive evidence in the form of rejected null hypotheses? How dare they?

They dare because they move beyond the familiar routine of “evidence-based” practice (or belief) to “science-based” practice. The former simply demands that belief and practice be grounded in the “best evidence available,” whereas the latter is far more specific on what is required for evidence to be credible. A science-based evaluation of a claim not only looks at empirical data and their statistical properties, but also at the plausibility and the coherence of the assumptions that go into the study. Swan et al. recall the brouhaha around Daryl Bem’s claim to have found statistical evidence for telepathic backward causation. Replication studies failed, but Swan’s point is that Bem’s claim was incoherent and thus implausible at the outset. I made the same point in this blog (e.g., here and here). Making and appreciating a strong argument about incoherence or a priori implausibilty requires critical thinking skills and knowledge of a lot of relevant content. This tends to be difficult work. Laziness, ignorance, and a false sense of tolerance conspire against it. Indeed, we often see the gullibers claiming the high moral ground, charging the critics with closed-mindedness, conservatism, or a lack of imagination. ‘Why can’t you admit that this tale might be true? What’s the harm in it?’

Swan et al. tell us about the harm. Focusing on a set of complementary and alternative healing practices, they rereview what supporters had considered the best evidence and find that little of it holds up to science-based scrutiny (I leave the details to your reading of their excellent article). Suffice it to say that most claims disintegrate when nonspecific effects (e.g., ) are rigorously controlled. At the same time, there is positive evidence (in the statistical sense) that many of these practices have nontrivial risks: infections from acupuncture needles, spinal injuries for chiropractic ‘adjustments,’ poisonings from herbal preparations or other dietary supplements. Moreover, many people who entrust their health to good-sounding alternatives withdraw from clinically tested methods (e.g., vaccines), get sicker as a result, and endanger the rest of us in the process. What is the proper level of tolerance here?

My lower back hurts. The chiropractor helps with heat treatment and stretches. The adjustments fill me with dread. Conventional medicine has been useless. The expensive images reveal nothing of diagnostic value (note that the docs are honest about that). Now what about this chakra business I heard about, or better yet, the qì? May the Qì be with you!

Source: J. Krueger

And then there is the Dodecahedron (in photo) as found in the “Mindfully into the future” congress, which I attended last month in the Hessian hills. Sit down within it, and it will all be better. It’s all energy (and money) after all.

Swan, L. K., Skarsten, S., Chambers, J. R., & Heesacker, M. (2015). Why psychologists should reject complementary and alternative medicine: A science-based perspective. Professional Psychology: Research and Practice, 46, 329-339.

Nachwort. Homeopaths in England have prepared 'preparations' with dust from the Berlin Wall, promising relief to those who suffer from 'mental blockages.' [sorry, I only have a source in German] Now, being homeopaths, they would have to dilute the preparation to the point that no actual Berlin Wall dust molecules are left for ingestion; only the ' ' thereof is supposed to linger - and help. Folks, I consider this idea ludicrous a priori, and foolish those who consider it testworthy.

Post-afterword. One of the commentators is uneasy about about the distinction between science-based and evidence-based belief and practice. I sympathize. I could only scratch the surface of this distinction in this post. Read Swan et al. and the sources they cite for more. Meanwhile, think of it this way: An unconstrained evidence-based approach respects any hypothesis, however ludicrous, as testworthy. This is an inefficient strategy and it creates huge opportunity costs. Consider the idea, floated by the English homeopaths, that the effectiveness of their preparation depends on the match between your complaint and the part of the Berlin Wall, from which their 'ingredient' was scraped. There is nothing that can be said, beyond most primitive appeal to , that can give this 'hypothesis' any plausibility. Testing it is wasteful and an insult to . I own a piece of the Berlin Wall. I hacked it myself off that loathsome structure. Next time I have a headache, or better yet, when I feel homesick for Berlin, should I not fix me a cup of tea and stir in some ground concrete? If you think that will work, can't we all? Can't I?

I recommend the entry on "A priori justification" in the Stanford Encyclopedia of for further reading.

And finally. The photo at the top was made by pointing the camera into an empty bottle of table wine from the Pays d'Oc. It was delicious.