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Homeopathy is perhaps the paradigmatic example of an alternative therapy: it claims the authority of a rich historical heritage, but its history is routinely rewritten for the PR needs of a contemporary market; it has an elaborate and sciencey-sounding framework for how it works, without scientific evidence to demonstrate its veracity; and its proponents are quite clear that the pills will make you better, when in fact they have been thoroughly researched, with innumerable trials, and have been found to perform no better than placebo.

Homeopathy was devised by a German doctor named Samuel Hahnemann in the late eighteenth century. At a time when mainstream medicine consisted of blood-letting, purging and various other ineffective and dangerous evils, when new treatments were conjured up out of thin air by arbitrary authority figures who called themselves ‘doctors’, often with little evidence to support them, homeopathy would have seemed fairly reasonable.

Hahnemann’s theories differed from the competition because he decided—and there’s no better word for it—that if he could find a substance which would induce the symptoms of a disease in a healthy individual, then it could be used to treat the same symptoms in a sick person. His first homeopathic remedy was Cinchona bark, which was suggested as a treatment for malaria. He took some himself, at a high dose, and experienced symptoms which he decided were similar to those of malaria itself:

My feet and finger-tips at once became cold; I grew languid and drowsy; my heart began to palpitate; my pulse became hard and quick; an intolerable anxiety and trembling arose … prostration … pulsation in the head, redness in the cheek and raging thirst … intermittent fever … stupefaction … rigidity…

and so on.

Hahnemann assumed that everyone would experience these symptoms if they took Cinchona (although there’s some evidence that he just experienced an idiosyncratic adverse reaction). More importantly, he also decided that if he gave a tiny amount of Cinchona to someone with malaria, it would treat, rather than cause, the malaria symptoms. The theory of ‘like cures like’ which he conjured up on that day is, in essence, the first principle of homeopathy.*

Giving out chemicals and herbs could be a dangerous business, since they can have genuine effects on the body (they induce symptoms, as Hahnemann identified). But he solved that problem with his second great inspiration, and the key feature of homeopathy that most people would recognise today: he decided—again, that’s the only word for it—that if you diluted a substance, this would ‘potentise’ its ability to cure symptoms, ‘enhancing’ its ‘spirit-like medicinal powers’, and at the same time, as luck would have it, also reducing its side-effects. In fact he went further than this: the more you dilute a substance, the more powerful it becomes at treating the symptoms it would otherwise induce.

Simple dilutions were not enough. Hahnemann decided that the process had to be performed in a very specific way, with an eye on brand identity, or a sense of ritual and occasion, so he devised a process called ‘succussion’. With each dilution the glass vessel containing the remedy is shaken by ten firm strikes against ‘a hard but elastic object’. For this purpose Hahnemann had a saddlemaker construct a bespoke wooden striking board, covered in leather on one side, and stuffed with horsehair. These ten firm strikes are still carried out in homeopathy pill factories today, sometimes by elaborate, specially constructed robots.

Homeopaths have developed a wide range of remedies over the years, and the process of developing them has come to be called, rather grandly, ‘proving’ (from the German Prufung). A group of volunteers, anywhere from one person to a couple of dozen, come together and take six doses of the remedy being ‘proved’, at a range of dilutions, over the course of two days, keeping a diary of the mental, physical and emotional sensations, including dreams, experienced over this time. At the end of the proving, the ‘master prover’ will collate the information from the diaries, and this long, unsystematic list of symptoms and dreams from a small number of people will become the ‘symptom picture’ for that remedy, written in a big book and revered, in some cases, for all time. When you go to a homeopath, he or she will try to match your symptoms to the ones caused by a remedy in a proving.

There are obvious problems with this system. For a start, you can’t be sure if the experiences the ‘provers’ are having are caused by the substance they’re taking, or by something entirely unrelated. It might be a ‘nocebo’ effect, the opposite of placebo, where people feel bad because they’re expecting to (I bet I could make you feel nauseous right now by telling you some home truths about how your last processed meal was made); it might be a form of group hysteria (‘Are there fleas in this sofa?’); one of them might experience a tummy ache that was coming on anyway; or they might all get the same mild cold together; and so on.

But homeopaths have been very successful at marketing these ‘provings’ as valid scientific investigations. If you go to Boots the Chemist’s website, www.bootslearningstore.co.uk, for example, and take their 16-plus teaching module for children on alternative therapies, you will see, amongst the other gobbledegook about homeopathic remedies, that they are teaching how Hahnemann’s provings were ‘clinical trials’. This is not true, as you can now see, and that is not uncommon.

Hahnemann professed, and indeed recommended, complete ignorance of the physiological processes going on inside the body: he treated it as a black box, with medicines going in and effects coming out, and championed only empirical data, the effects of the medicine on symptoms (‘The totality of symptoms and circumstances observed in each individual case,’ he said, ‘is the one and only indication that can lead us to the choice of the remedy’).

This is the polar opposite of the ‘Medicine only treats the symptoms, we treat and understand the underlying cause’ rhetoric of modern alternative therapists. It’s also interesting to note, in these times of ‘natural is good’, that Hahnemann said nothing about homeopathy being ‘natural’, and promoted himself as a man of science.

Conventional medicine in Hahnemann’s time was obsessed with theory, and was hugely proud of basing its practice on a ‘rational’ understanding of anatomy and the workings of the body. Medical doctors in the eighteenth century sneeringly accused homeopaths of ‘mere empiricism’, an over-reliance on observations of people getting better. Now the tables are turned: today the medical profession is frequently happy to accept ignorance of the details of mechanism, as long as trial data shows that treatments are effective (we aim to abandon the ones that aren’t), whereas homeopaths rely exclusively on their exotic theories, and ignore the gigantic swathe of negative empirical evidence on their efficacy. It’s a small point, perhaps, but these subtle shifts in rhetoric and meaning can be revealing.