A brief reference on the web site The Quackometer recently drew my attention to a very short book (really more of a pamphlet, in the historical sense) by Dr. Worthington Hooker, Lessons from the History of Medical Delusions, which I thought might be of interest to readers of this blog. Though published in 1850, the book contains many eloquent observations that are just as relevant to understanding how pseudoscience and quackery persist and even flourish in what we otherwise assume to be an age of scientific medicine. The book is available online as a Google eBook, and relatively cheap printed facsimiles are available as well.
Dr. Hooker was a physician, a professor at Yale, and an outspoken critic of homeopathy in it’s early days. His critique of homeopathy still resonates today, and has long drawn the ire of Hahneman loyalists, such as this one who makes reference to Dr. Hooker’s, “periodical fulminations for the destruction of Homoeopathy that have appeared like locusts or cholera at certain dates.” Though Dr. Hooker wrote an entire book discussing homeopathy, Homeopathy: An Examination of its Doctrines and Evidences, he does spare a few words here for this less-than-venerated practice:
The error I have been illustrating is carried to an extreme by the Homeopathist. He attributes palpable results to doses of medicine which are so small that they cannot produce any perceptible effect except by miracle.
He also includes a lengthy and preposterous example of a homeopathic proving, taken from a homeopathic text of the time, illustrating the absurdity of simply listing every imaginable (and imagined) experience following the taking of a substance and then attributing the entire list to that substance in order to guide the selection and use of homeopathic remedies. However, the focus of this booklet is to illustrate more generally the sorts of errors in thinking that lead even otherwise intelligent and reasonable people to believe such nonsense.
And Hooker makes a specific point of reminding us that belief in medical absurdities is not by any means a characteristic only of the unintelligent, the uneducated or the past.
The history of medical delusions most copiously illustrates the truth, that folly is very far from being confined to fools.
The present generation laugh at the follies of the past but have quite as great follies of their own, an follies too of a similar character, and products of the same fundamental errors.
The majority [of believers in quackery] is made up of those who are more or less intelligent and rational on most subjects, but who…are especially deluded on the subject of medicine…The exposition I make is not a partial one. It is not a one-sided argument-a plea for the doctors against the people. But it is an attempt to show how both doctors and people have ever been liable to error, and how they have been alike in the common elements, if not in the forms and modes and fashions of their delusions.
The medical profession, like the community at large, is made up of fallible men, and the elements of delusion are the same in the one class as in the other [though] the error of the physician would be refined, and would have the pomp and circumstance of erudition.
Error gilded with the pomp and circumstance of erudition….That certainly brings a few names to mind, eh?
Some of the specific examples he uses are fine tidbits of historical minutia. Apparently, one of the founding fathers of chemistry, Robert Boyle, also expressed his belief that dysentery could be cured through use of the thighbone of an executed criminal. And according to Hooker, Francis Bacon, that luminary of critical thinking and scientific philosophy, advocated for applying healing salves to the weapon that made a wound rather than the wound itself (though given the loathsome nature of many therapeutic unguents of the time, this may not have been a bad idea since apply them to wounds doesn’t sound wise).
So what are the common “elements of delusion” that Hooker wishes to warn us of? He begins with the post hoc ergo propter hoc fallacy.
The first [element] which I shall notice is the too ready disposition to consider whatever follows as a cause as being the result of that cause.
He then points out the most obvious reason why this sort of reasoning so often misleads us in medicine:
The most important of the confounding causes is “vis medicatrix naturae, or the tendency there is in the system to remove disease and cure itself….there is in the system a tendency to spontaneous restoration in case of injury and disease…This tendency is the chief agency in most cases in curing disease. Sometimes it is the only one; and very often it effects a cure in spite of the mistaken and officious interference of art.
And yet quacks, and even physicians, and the public generally, are very prone to leave this agency out of view, and to attribute cures, as a matter of course, entirely to some favorite remedy which has been used. This disposition is the chief source of medical errors of all classes of men.
Hooker also touches on several other key sources of erroneous conclusions in evaluating medical theories, including confirmation bias, availability bias, anchoring, premature closure, sloppy use of analogous reasoning, passionate commitment to theories without empirical evidence, and medical fads, though all describe in a language rather more poetic than we would ordinarily use today.
He then goes on to talk about the issue of the commercial and political success of medical nonsense, which are certainly still relevant issues often discussed here.
So extensive is the popular delusion in regard to quack medicines, that the nostrum system has become an organized system, with an enormous machinery of certificates and advertisements. It has become a monstrous business interest, and is linked in with a thousand ties with other business interests. So powerful is it in this respect, that it has almost entirely subsidized the press, forcing it to be silent except when it speaks in it’s favor. The same may be substantially said when speaking of the action of legislatures on this subject.
Similarly, Hooker touches on the unfortunate aura of legitimacy that attaches to quack therapies when they are embraced by what he calls “medical men in good standing,” which could certainly be applied to the quackademic medicine phenomenon and the endorsement of medical nonsense by the likes of Dr. Oz and others.
Despite the eloquent expression of many issues associated with medical nonsense that are as relevant today as they were in 1850, not all of Dr. Hooker’s book will resonate with a modern audience. Apart from the florid prose style of the time, and the unabashedly sexist language, he scoffs a bit “the skeptic,” who he describes as sitting in “his ‘doubting castle’ well-fortified against all the shafts of truth.” He also was a fan of bloodletting as a remedy, and sneered at the research of Pierre Charles Alexandre Louis and others who demonstrated its lack of effect. In general, he was no fan of the “numerical” methods which have since developed into epidemiology, and he was overly respectful of the experience and judgment on individual doctors. Citing the same sloppy reasoning as is often used by modern proponents of alternative therapies, he argues that such “numerical observations…can be of no practical use to the physician in deciding in regard to any individual case…”
However, as a whole this little historical gem is strikingly applicable to the issues this blog deals with today. And it ends with a nice description of the gradual and imperfect process of vetting ideas through scientific inquiry, from initial unjustified enthusiasm to a gradual withering of bad ideas and a fitting of good ones into their appropriate but limited places.
While many remedies, once potent to cure in the public estimation, have….been wholly discarded, others, which have more real merit, while they have lost the extravagant reputation of their nascent state, have, under the watchful eye of experience, gradually obtained very nearly their right valuation, and the circumstances which should regulate their use have been ascertained with considerable accuracy. Others, in great numbers, are now going through this searching process; and others still are just now wearing the brilliant honors of an enthusiastic reception.
He also suggests, mistakenly I hope, that direct attacks on medical nonsense rarely have a salutary impact on the popularity of such practices. However, he also describes with some hopefulness the goal of his book, which I think to some extent describes the purpose of this blog as well.
No delusion however fiercely it may have been attacked was ever killed. Each after having withstood all assaults, has laid itself down o die in the most quiet manner, benumbed into the sleep of death by the chill of popular neglect, while the warm breeze of popular favor which it once enjoyed are now bestowed upon some other delusion…
And such exposition as this essay presents, of the common causes of medical delusion, both in the profession and in the community, will, I believe, commend itself to the reason and common sense of such persons, and will therefore have some influence, in connection with other kindred efforts, in deterring them from giving heir patronage to quackery in any form…