Veterinary homeopathy and the naivety of reductionists

Charles Foster, 2018

To read the full article, please see here.

For anyone who can’t be bothered to read all of this post, this is not a defence of homeopathy’s claims of efficacy. Just saying.


The Council of the Royal College of Veterinary Surgeons (the RCVS is the body charged by statute with regulation of the UK veterinary profession) recently issued a position statement on ‘complementary and alternative therapies, including homeopathy’. It was an outright attack on non-conventional treatment modalities. The whole text of the statement is here


Homeopathy bore the brunt of the attack.


Here is the core of the statement:

…we expect that treatments offered by veterinary surgeons are underpinned by a recognised evidence base or sound scientific principles. Veterinary surgeons should not make unproven claims about any treatments, including prophylactic treatments.
Homeopathy exists without a recognised body of evidence for its use. Furthermore, it is not based on sound scientific principles. In order to protect animal welfare, we regard such treatments as being complementary rather than alternative to treatments for which there is a recognised evidence base or which are based in sound scientific principles.

I hold no brief for homeopathy (though I am interested in veterinary acupuncture), but this is a statement of, at best, very remarkable naivety. It is, really, a religious naivety, of the sort you see amongst Young Earth Creationists.


The statement represents a touching belief in the integrity and infallibility of scientific publishing, and hence of evidence-based medicine. Has the Council never read about the unrepeatability of many of the headline studies?


Nature (for instance) reported in 2012 that the results of only 6 out of 53 papers deemed ‘landmark’ studies in haematology and oncology could be reproduced. That’s 11%. The authors of the Nature paper commented:


‘Some non-reproducible preclinical papers had spawned an entire field, with hundreds of secondary publications that expanded on elements of the original observation, but did not actually seek to confirm or falsify its fundamental basis.’


A Bayer Healthcare team in 2011 reported that only about 25% of published preclinical studies could be validated to the point at which projects based on the reported findings could continue.


Perhaps the most salutary findings come from the results of a 2016 survey of 1576 researchers carried out by Nature. More than 70% of respondents had tried and failed to reproduce another scientist’s experiments, and more than 50% had failed to reproduce their own. These results were very similar to those obtained in a survey of nearly 900 members of the American Society for Cell Biology.


Until very recently there has not been much enthusiasm for addressing the issue of non-reproducibility. It’s not hard to understand why. ‘Sorting discoveries from false leads’, commented Nature (2016), ‘can be discomfiting. Although the vast majority of researchers in our survey had failed to reproduce an experiment, less than 20% of respondents said that they had ever been contacted by another researcher unable to reproduce their work…. That may be because such conversations are difficult. If experimenters reach out to the original researchers for help, they risk appearing incompetent or accusatory, or revealing too much about their own projects.


A minority of respondents reported ever having tried to publish a replication study. When work does not reproduce, researchers often assume there is a perfectly valid (and probably boring) reason. What’s more, incentives to publish positive replications are low and journals can be reluctant to publish negative findings. In fact, several respondents who had published a failed replication said that editors and reviewers demanded that they play down comparisons with the original study.’


What’s my evidence for my assertion that scientists are trusting believers, whose belief in the integrity of their paradigm is unshakeable? Well, here’s some. In the 2016 Nature survey 52% of the respondents agreed that there is a ‘significant’ crisis of reproducibility. Fine. But fewer than 31% thought that failure to reproduce published results meant that the result was probably wrong, and most respondents said that they still trusted the published literature.


That is pure cognitive dissonance of an essentially religious kind. It is unskeptical and unscientific.


Yet this is the belief that lay behind the RCVS’s position statement.


One would have hoped, too, for a rather more worldly-wise view from the RCVS on the vested interests of drug companies. Ben Goldacre, swashbucklingly but reasonably, summarises:


‘Drugs are tested by the people who manufacture them, in poorly designed trials, on hopelessly small numbers of weird, unrepresentative patients, and analysed using techniques which are flawed by design, in such a way that they exaggerate the benefits of treatments. Unsurprisingly, these trials tend to produce results that favour the manufacturer. When trials throw up results that companies don’t like, they are perfectly entitled to hide them from doctors and patients, so we only ever see a distorted picture of any drug’s true effects. Regulators see most of the trial data, but only from early on in a drug’s life, and even then they don’t give this data to doctors or patients, or even to other parts of government. This distorted evidence is then communicated and applied in a distorted fashion. In their forty years of practice after leaving medical school, doctors hear about what works through ad hoc oral traditions, from sales reps, colleagues or journals. But those colleagues can be in the pay of drug companies – often undisclosed – and the journals are too. And so are the patient groups. And finally, academic papers, which everyone thinks of as objective, are often covertly planned and written by people who work directly for the companies, without disclosure.’1


What all this comes to is that if one should only prescribe drugs with an absolutely unarguable record of efficacy and safety (I’ll come to safety in a moment), almost none of the drugs in the conventional pharmacopeia could be prescribed. The conventional clinicians would be hoist with their own petard.


Perhaps they are to some extent aware of the power of this objection. Perhaps that is the reason for their curious formulation: ‘…we expect that treatments offered by veterinary surgeons are underpinned by a recognised evidence base or sound scientific principles.’ (Emphasis added).


The ‘or’ appears to recognize that there may be some properly prescribable treatments that are not ‘underpinned by a recognized evidence base…’ They are properly prescribable because they are ‘underpinned….by sound scientific principles’. This can be fairly translated as: ‘It might not be possible to prove that X works, but because we can think of a way that it might, it’s OK to use it.’


There are many things that might be said about this. One will do for now.


It is that, again, this is a statement of belief: not, this time, in the integrity of the system (reproducibility, peer review etc) that calls itself ‘evidence-based medicine’, but in the presumption that to understand a mechanism of action at a microscopic level is to predict reliably a macroscopic outcome. Why? The explanation is rather quaintly 18th century: animals and humans are machines, and therefore to understand mechanisms is to understand the whole creature. The more minute the locus of inspection, the greater the explanatory power that results from the inspection, and the more minute the locus of clinical intervention, the better.


It often starts perfectly reasonably: ‘We can see that drug X could interfere with biochemical pathway Y’, says the apologist, ‘and if it does, there would be less of undesirable product Z in the kidneys.’ But then comes the step of pure faith that we see in the RCVS statement: if something might work at a fundamental level, it does – notwithstanding the absence of any clinical evidence. The mechanism is everything: more important, even, than the clinically unaffected or adversely affected patient (though, to be fair, the RCVS do say that animal welfare is their priority). Philosophically, though, it’s abstraction gone mad: adherence to the model is more important than the patient whom the model purportedly serves. This is a very literal form of reductionism: animals and humans should be understood as a conglomeration of systems: organs, cells, biochemical pathways, and genes, and treatment should be directed at these tiny systems, rather than at the whole humans or non-human animals. It’s not surprising. Few western scientists study – except momentarily – whole live animals or whole live humans, and medical and scientific preferment comes from knowing a lot about a tiny area.


This is a way of looking at humans and non-human animals, but it is not the only way. Most non-western medicine looks at whole creatures – as the reductionists do in real life. When they get home from the clinic or the lab to their families, they are far more interested in their whole children than in their children’s livers or their bile metabolism.


There is, then, a rather offensive colonialism about the reductionist assumptions of the west, and a striking inconsistency between the 9 to 5 and the 5 to 9 behaviour of the reductionist believers. One might also observe that, to say the least, the explanatory power of reductionism seems to be limited. You needn’t posit the reality of telepathy or ghosts to say that: you just need to look, as we have, at the failure of reproducibility – the very failure that forced the RCVS to put in its rather embarrassing ‘or’ caveat.


Having been critical of the way that orthodox veterinarians approach the question of clinical evidence, it’s worth looking briefly at whether there is really such a gulf between the evidence for orthodox veterinary medicine and homeopathy.


This doesn’t entail a trawl through the literature on homeopathy. (I’m not qualified to do that, and I haven’t tried.) It’s a matter of very basic observations. To be clear: It seems improbable that homeopathy ‘works’ – in the sense of being more efficacious than a placebo. But perhaps it does. At least sometimes. The history of science is cluttered with the discovery of exhilarating improbabilities, and it is not at all improbable that there are more things in heaven and earth than are dreamt of by the directors of Glaxo or Pfizer. The possibility of homeopathy’s efficacy should be investigated rigorously and with an open mind. If any efficacy is attributable to a particularly potent placebo effect, that seems to me to be a reason for encouraging, not discouraging, its use.The placebo effect forms a significant part of the efficacy of most medicines.


All that can be said about most orthodox medicines is that they work unless they don’t. The same can be said about homeopathic medicines. Orthodox clinicians will protest: ‘But we use these medicines every day: we see that they work’. Homeopathic clinicians, pet owners and farmers (a usually very skeptical crowd, with the bottom line clearly in view) say, apparently, exactly the same thing. It seems patronizing to say that they are all deluded.


A much repeated objection to homeopathic medicine is that (however poor the evidence base for orthodox medicine) there are no robust clinical trials vindicating homeopathic medicine. Whether or not that assertion is true, I simply don’t know. But I have heard repeatedly, anecdotally, that it is tremendously hard to get a study affirming homeopathy published in a mainstream journal. It wouldn’t surprise me. I’d imagine the conversations go like this:


‘Here is a paper showing that homeopathy works.’
‘But homeopathy doesn’t work. It can’t.’
‘But this shows that it does’.
‘There is no way that it can. The paper is rejected.’


The response of the journal is of course profoundly unscientific. It’s that fundamentalism again. It’s scientism. So the paper gets published in a homeopathy journal, which needn’t be cited because it’s a homeopathy journal. Simple as that. It’s a shame.


A word about safety. No one has ever contended that homeopathy causes active harm. No one can dispute that almost all orthodox medications have a long list of recorded adverse reactions. No one should dispute, either, that for a drug to be tried (as appears to be endorsed by the RCVS) on the basis that its mechanism appears therapeutically promising, is to expose a patient to all sorts of potential unforeseen adverse consequences.


It may therefore have been more logical for the RCVS, which justified its statement against complementary medicines by reference to animal welfare, to have spent its time ensuring that owners are properly warned about the manifest and manifold risks (many of which are in that scientific literature) attendant on the use of conventional therapies.




1. Bad Pharma (201), Fourth Estate, p. xi