Homoeopathy and Science

Whenever a pro-homoeopathy letter or article appears in the veterinary press, there is invariably a claim to the effect that the discipline is firmly based on sound scientific principles (for example Saxton, 2003.)  Which scientific principles would these be, then?

The law of similars

Hahnemann's original notion seems to have been that clinical signs such as fever or vomiting are manifestations of the body's attempt to heal itself.  Therefore, rather than trying to eliminate these signs, a better effect will be achieved by stimulating it to more of the same.  This theory is seldom explicitly propounded today, but it seems to be the basis for the otherwise baffling assertion that homoeopathy is addressing the underlying disease processes while the rest of us are merely fiddling around suppressing the symptoms.

The modern version of this is the proposal that homoeopathy works by activating the body's natural healing mechanisms.  Proponents sometimes speak of finding the 'right signal' to trigger the system into recovery mode.  However, it's difficult to know what is actually meant by this.  All medicine relies absolutely on the body's natural healing mechanisms - no medicine or surgery ever cured a disease or healed a wound in a corpse.  Scientific medicine mainly aims to correct whatever is preventing healing from proceeding normally, but it also, on occasion, attempts to stimulate or kick-start a desired reaction.  Vaccination is the most obvious example, and the superficial parallels (beneficial effect of a tiny dose of 'what ails you') are often invoked by homoeopaths in support of homoeopathic methods. However, while scientific medicine can point to plausible modes of action for its endeavours, this does not apply to homoeopathy, which instead invokes the elusive mediaeval notion of the 'vital force'. Indeed, although the Faculty of Homoeopaths supports conventional vaccination, many individual homoeopaths bitterly oppose the practice, and some of the most vocal members of the anti-vaccination lobby are homoeopaths.

The law of infinitesimals

Why might an extremely dilute solution remain efficacious, even when it's so dilute that no molecules of the original solute remain?  Hahnemann asserted that contact is unnecessary to ensure potency, referring to unseen forces such as gravity, magnetism and the transmission of infectious disease, and likened the release of the 'latent power' of the remedy (by shaking) to the raising of the temperature of metal plates by rubbing them together.  However, this notion has been very sensibly abandoned, leaving the way open for more imaginative attempts to tie the phenomenon in to modern theories in chemistry and physics.

MacLeod (1989), then president of the British Association of Homoeopathic Veterinary Surgeons, stated that, "Homoeopathic remedies are energised products and depend on their efficacy by release of this within the body."  A more recent veterinary article asserts that "the substance itself is not the important ingredient but the imprint it leaves on the carrier material" (Mueller, 2003).  Park (1997) considers a number of suggestions as to how this imprint might occur, including clusters of water molecules arranged in specific patterns, arrangements of isotopes such as deuterium or oxygen-18, and 'coherent vibration' of water molecules.  Other suggestions over the years have included something called a 'biophoton', some interestingly creative interpretations of chaos theory, Brownian motion, giant polymer chains of water molecules, and 'kinetic energy'.  Unfortunately none of these hypotheses has yet been recognised by the chemists or physicists whose work is invoked in their support.

Many homoeopaths still rely on the infamous experiments of Benveniste (Davenas et al., 1988) to support their assertions.  Huizenga (1993) compared this affair to the similar fiascos of N-rays, polywater and cold fusion, and commented, "The search for verification of this theory will go on because a sizeable fraction of French physicians prescribe homoeopathic medicines.  Much has been written about the 'Benveniste effect', however, there is no reproducible experimental evidence to support it.  The effect clearly has the characteristics of pathological science, namely 'the science of things that aren't so'."  The claim was the subject of a large, tightly-controlled study broadcast in November 2002 by BBC2's Horizon programme, during which Benveniste presented himself not as a dedicated homoeopathic researcher (which he is), but as a scientist who had stumbled on an unexpected effect by chance.  He also refrained from explaining how he had subsequently (in 1998) shown that the memory of water can be recorded digitally and even transmitted over the Internet - presumably in collaboration with Uri Geller and David Icke?

To be absolutely accurate, although Horizon did investigate the notorious Benveniste affaire in depth, the actual experiment performed was in fact the version used by Professor Madeleine Ennis of Queen's University, Belfast, which uses histamine instead of IgE.  Prof. Ennis, in collaboration with a number of associate laboratories (including that of Boiron, France's largest manufacturer of homoeopathic remedies) has more recently published work suggesting that this effect can be reproduced independently (Belon et al., 2004).  However, this only seems to work among her little circle of homoeopathic friends, and the wider world of physics and chemistry remains unimpressed.  Just as lacking in impact has been the work of Rey (2003), who claims to have demonstrated thermoluminescence specific to the original solvent in solutions diluted beyond Avogadro's limit.  Although nobody seems to be rushing to revise the basic laws of chemistry to accommodate these alleged findings, this doesn't prevent homoeopathic proponents from announcing that their case is now proven.  None of them seems quite to have noticed that going from these (highly questionable) results to the conclusion that homeopathic remedies have a therapeutic effect in vivo is about as well-founded as going from a demonstration that the more you dilute a sugar solution the less sweet it tastes, to the instant conclusion that insulin is an effective treatment for diabetes.

In spite of so much creative effort, the search for the elusive mechanism of action has yet to bear any convincing fruit.   Gregory (2003) concedes that the mode of action is unidentified, but declares that "the enigma of the potentised remedy will be solved within the paradigm of quantum mechanics."  Quantum theory has been invoked very recently by a few medical homoeopathic authors (Walach, 2000; Milgrom, 2002; 2003a; 2003b; Weingärtner, 2003), apparently in reaction to the growing realisation that not only can no rational mode of action be postulated, but that the alleged dramatic clinical effects cannot be substantiated in well-designed blind trials.  Things then start to get really surreal, and this aspect is discussed further below.

Everyone still seems rather hazy about how successive dilution actually increases the potency of the remedy, and how energised or imprinted water manages to influence cellular metabolism - especially when, as is often the case, the patient takes not the water itself, but a lactose pill onto which it has been dropped and then allowed to evaporate.  The mechanism by which the diluent only potentises the desired therapeutic effect of the designated remedy, and not its toxic effects or any of the properties of any contaminant molecules, also remains to be elucidated.  Perhaps these are suitable fields for the further research which is so often called for?

The principles of homoeopathy fly in the face of the basic sciences of chemistry and physics, also biochemistry, molecular biology and pharmacology.  It makes cold fusion look eminently practical.  If it were to be shown tomorrow that there is a demonstrable and reproducible effect involved, it would require major rewriting of the accepted physical and chemical ways of looking at the universe.  Still, we must keep an open mind, mustn't we?

Homoeopathy and anthropology

The one scientific discipline which resonates completely with the claims of homoeopathy is in fact anthropology.  In his seminal work The Golden Bough (first edition 1890, but current references are to the single-volume 1922 edition), Sir James Frazer explored and categorised an enormous range of magical thinking and beliefs.  His chapter on 'Sympathetic Magic' makes fascinating reading.  Here Frazer divides the principles of thought on which magic is based into two main categories: the 'Law of Similarity', which states that "like produces like, or an effect resembles its cause"; and the 'Law of Contagion', which states that "things which have once been in contact with each other continue to act on each other at a distance even after the physical contact has been severed."  The parallels are obvious.

Frazer was working in the late 19th and early 20th centuries, about a hundred years after Hahnemann.  Even then many scientists saw debunking homoeopathy as something akin to shooting fish in a barrel (for example Holmes, 1842).  However, it was still a semi-respectable branch of medicine patronised by many influential personages, including Queen Victoria.  It is likely that Frazer was reluctant to come straight out and include such an apparently respectable and (on the face of it) non-magical practice in his study of primitive superstition and savage ritual, and in fact he never actually names either Samuel Hahnemann or medical homoeopathy in his work.  Nevertheless he clearly recognised a prime example of Sympathetic Magic when he saw it, and this can easily be appreciated from his choice of terminology.  With the entire dictionary at his disposal, he rejects both 'Imitative Magic' and 'Mimetic Magic' to describe charms based on the Law of Similarity, and settles on, yes, 'Homoeopathic Magic'!  Although he heroically refrains from employing the term similia similibus itself (a tag Hahnemann may have originally found in Paracelsus, but which he had made his own just as much as his invented word 'homoeopathy'), he frequently repeats its English equivalent, 'like produces like'.  Many of his successors have gone the whole way, and we now find similia similibus in the anthropological literature describing such things as voodoo dolls, just as naturally as it occurs in the literature of homoeopathic medicine.

Frazer's opinion of the 'undeveloped' mind-set which actually believes and practices such charms is very obvious.  'A spurious system of natural law' - 'a false science' - 'complete ignorance of intellectual and physiological processes' - 'mistake' - 'misapplication of the association of ideas' and so on.  It's difficult to escape the impression that this invective is aimed not just at the primitive magician, but also at Hahnemann and his disciples, and there is no doubt at all that medical homoeopathy fits right in there with all the colourful examples of Sympathetic Magic which are actually described.  Although it is the 'Law of Similarity' which Frazer specifically labels 'Homoeopathic Magic', this is only half the story - Hahnemann's 'Law of Similars'.  The 'Law of Infinitesimals' is of course a classic example of Frazer's 'Law of Contagion', whereby efficacy remains in something (the diluent) which was once in contact with the remedy, even though it is no longer in contact.  Voodoo healing combines the two laws in much the same way, with the doll being 'like' the patient, and its power enhanced by the introduction of either a separated part of the patient's body (hair, nail, or even faeces) or something (such as a garment) which was once in contact with it.

This is not to suggest that homoeopaths are dabbling in the occult.  Hahnemann and his followers undoubtedly believed, and still believe, that they are practising science.  However, trying to understand the thought processes in terms of scientific reasoning is like trying to nail jelly to the ceiling.  Dogmatic assertion of allegedly self-evident 'truths' (such as 'like cures like') (Hoare, 1990), a refusal to reappraise theory or practice in the light either of fundamental understanding or experimental results (Couzens, 1989), the postulation of mysterious unmeasurable 'energies' (MacLeod, 1989; MacLeod, 1991), and attributing a major influence to the 'intent' of the practitioner (Thoresen, 2003), are not science.

To take a very recent example (Horizon, 2002), the statement ".... in colds and hay fever something we often use is allium cepa, which is onion - and of course we all know the effects of chopping an onion, the sore, streaming eyes, streaming nose, sneezing - and so we would use allium cepa, onion, for a cold with similar sorts of features."  This sort of rationale belongs far more naturally in one of Harry Potter's Herbology classes at Hogwarts than a medical school, and the fact that it was said by Dr. Peter Fisher, homoeopath to the Queen, surrounded by all the trappings of Harley Street medical practice, doesn't alter its essentially magical nature.

It's not unusual to hear homoeopathy described as 'witchcraft'.  While this may be intended as an idle insult, if we can strip the term of its negative and derogatory connotations, it is actually a simple statement of fact.  Indeed, this has been explicitly recognised by some members of the homoeopathic community itself, most notably Walach (2000), who attempts to explain how "the scientifically obscene word 'magic' can be understood in an inoffensive way", declaring that:

Although the original substance is diluted, it is still in some way 'present' and effective.  This presence, I will contend in this paper, is a magical, not a causal presence, ....  Magical presence and effects are wrought by signs, not by causes.  In this sense, homeopathy is effective in a non-local way: it acts by magically activating connectedness.

Later, he elaborates:

The homeopathic medicine is a sign which mediates the meaning between a mental-psychological state, the illness in the patient, and the physical realm of bodily functions, elements of nature, and the like.  It acts via the original interconnectedness of all beings, which is activated, as in magical rituals, by the homeopathic ritual of case taking, remedy preparation, repertorization and remedy prescription.

This paper in fact contains a very lucid appraisal of the wealth of evidence in the literature demonstrating that homoeopathic remedies do not show a repeatable effect beyond placebo, and it appears that it is this weight of evidence which drives the author to the paradigm of magic.  The Frazerian connections are however not acknowledged, and other avenues such as quantum entanglement are explored as possible "explanations" for the supposed interconnectedness.

Other authors (Milgrom, 2002; 2003a; 2003b; Weingärtner, 2003) have followed Walach in postulating a "non-local" effect as the mode of action for homoeopathy, and although they do not themselves use the word 'magic' but prefer to describe their thesis entirely through a metaphor drawn from quantum mechanics ("patient-practitioner-remedy (PPR) entanglement"), the essential thrust is the same.  According to this hypothesis, the mind (belief or understanding) of the homoeopath is essential to any effect which the remedy exerts.  The three components of the system entangle, or influence each other in some non-physical way, so that the homoeopath's understanding acts through the medium of the remedy to achieve a cure of the patient's illness.  This is held to explain both the lack of any pharmacological mode of action asociated with the remedy, and the fact that believing homoeopaths (allegedly) achieve extremely good results in a clinical situation while the same remedies in a blind trial conducted by non-believers demonstrably have no effect.  It also appears to explain the very wide variety of homeopathic methods which are claimed to be effective, again in the hands of believers, and the fact that efficacy appears to remain even if there has been a mistake or a misunderstanding in the preparation of the remedy.

One veterinary author has published in a very similar vein.  Thoresen (2003) refers to quantum theory only in passing, but describes the intent ("yì", a term drawn from acupuncture, which it is held acts in the same way) of the practitioner as by far the most important element in the success of homoeopathic treatment.  He also comes to this conclusion via an appreciation of the fact that homoeopathy only seems to work for the believing homoeopath, and not for the unbeliever or in a blind trial situation.  Even though none of these authors employs the term 'magic', and might perhaps reject it angrily, this would seem to be little more than a disagreement in semantics.  What else, realistically, are we supposed to call it?

(As an aside, if any homoeopath can actually demonstrate under controlled conditions that this is a real effect rather than pure imagination, he is a sure thing for the Million-Dollar Paranormal Challenge.  Even the ability to distinguish between a known, identified 30C remedy and a sham preparation in a "proving" situation would net the cash.  However, despite the fact that homoeopaths imply that they can do this easily, the JREF still seems to be stubbornly hanging on to its money.)

The question of magical thinking in complementary and alternative medicine has been considered in more detail by Stevens (2001).  He points out that such thinking is a basic mechanism of human cognition, and discusses the theory that the laws of similarity and contagion are a primitive and deep-seated form of reasoning, an early stage on the road to true rationality, before mode of action became an integral part of the cause-and-effect process.

The notion that the human mind has mystical powers to influence objects and events is also a very deep-rooted concept.  Children attempt such feats spontaneously, and often incorporate them into games.  Telepathy and telekinesis are almost universally-recognised concepts which frequently feature in imaginative fiction.  The figure of the magician, with learned or innate power to command matter and energy by means of spells or rituals, is familiar to virtually all cultures, and although there are few who believe that Harry Potter is a documentary, the image is an extremely popular one in developed western society.

This all goes a long way towards explaining the persistent acceptance of homoeopathic doctrines, even among the medically educated, despite repeated studies and arguments reiterating their fallacies.  Hahnemann's propositions press some very fundamental buttons in the human psyche, and even those who ought to know better are liable to be seduced by his concepts.  At this level of cognition the desire to "believe" can be extremely compelling, and as a result one usually finds that the very last people who are prepared to "keep a open mind" about the value of homoeopathy are its proponents themselves.

[Homeopathy - the Test. A critical review of the Horizon programme which failed to win James Randi's million dollar prize.]

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