The 'father' of homeopathy was Samuel Christian Hahnemann, born in Dresden, in 1755. Despite his humble background - his father worked in a porcelain factory - he acquired a good education, became fluent in eight languages, and studied chemistry and medicine. He then set up in practice as a physician. But the accepted medical customs of his day, which included excessive purging, blood-letting, and cavalier prescribing of drugs which often caused more suffering than they cured, gnawed at his conscience, and after a few years he turned to translating rather than doctoring to earn his living.

It was while he was translating a treatise on herbs by a Dr Cullen of Edinburgh that he came across the tiny seed which was to flower into a whole new system of medicine. Cullen stated that quinine, an astringent substance purified from the bark of the cinchona tree (Cinchona calisaya), was a good treatment for malaria because it was an astringent. Why, Hahnemann wondered, should quinine have an effect on malaria when other, more powerful, astringents did not? He decided to investigate. For several days he dosed himself with quinine and noted down his reactions in great detail. It seemed that in a healthy person, himself, quinine produced all the symptoms of malaria - fever, sweating, shivering, weakness. Was this why it also cured malaria?

Fascinated, Hahnemann repeated the quinine tests, which he called 'provings', on his acquaintances, again noting their reactions in meticulous detail. He then went on to test other substances in widespread use, such as arsenic, belladonna, and mercury. There were strict requirements for the people involved in these provings. They had to be healthy in mind and body; they could not take anything which might confuse the results, such as alcohol, tea, coffee, or spicy foods; and they were to avoid 'all disturbing passions'.

Hahnemann found that people's responses varied. Some of his volunteers showed one or two mild symptoms in response to a particular substance, but others experienced vigorous reactions with many and varied symptoms. The symptoms most commonly found for each substance he called 'first line' or 'keynote' symptoms. 'Second line' symptoms were less common, and 'third line' symptoms rare or idiosyncratic. Together these symptoms added up to a 'drug picture' of the substance concerned.

Using the results of his provings, Hahnemann went on to test various substances on sick people. But before he did so he questioned them thoroughly about their symptoms, general health, way of life, and attitudes, and gave them a physical examination. From each interview and examination he built up what he called a 'symptom picture', then prescribed the substance whose drug picture most closely matched it. The closer the match, the more successful the treatment. What he had suspected from his early experiments with quinine was indeed proving to be the case: a remedy and a disease which produce very similar symptoms cancel each other out in some way. The adage similia similibus curentur, 'like may be cured by like', was true. The name he gave to this new principle of healing was 'homeopathy'.

This was not the end of the story, however. To Hahnemann's dismay some of his patients reported that their symptoms actually got worse before they got better. To prevent such 'aggravations', as he called them, Hahnemann started to dilute his remedies. First he made a tincture of the substance concerned, leaving it to stand in a solvent, usually pure alcohol, for one month. He then strained off the liquid, the 'mother tincture'. Then he took one drop of mother tincture and added it to 99 drops of pure alcohol, a dilution factor of 1:100. To mix the one drop with the 99 thoroughly he 'succussed' the mixture by repeatedly banging it on a hard surface for a specific length of time. The dilution process could be repeated again and again, with each successive dilution having one hundredth the strength of the preceding dilution. If the substance was insoluble, it was triturated, or ground up, before being dissolved into solution.

To Hahnemann's surprise, diluted remedies not only forestalled 'aggravations' but seemed to act much faster and more effectively. They were, paradoxically, weaker but more potent. The process of successive dilution and succussion 'potentized' the original substance in a way which is difficult to explain.

It is not difficult to imagine the scorn which Hahnemann's contemporaries poured upon his claim that weaker remedies produced stronger effects. This ran, and still runs, completely counter to the principles of clinical pharmacology. At dilutions above the twelfth centesimal potency, does even one molecule of the original substance remain in solution? Modern physics affords a glimmer of an explanation why the energies of the original substance persist through successive dilutions and succussions, but how did Hahnemann answer his critics two centuries ago? Then, as today, the cures achieved by homeopathy are real. They cannot be dismissed because the mechanism of cure is not fully understood.

Being a chemist, Hahnemann knew that whatever active principles his dilute remedies contained, they could only be present in infinitesimal quantities. And yet the merest trace of them was enough to produce a strong effect. At some level in the body, he reasoned, there must be something which responds to such tiny hints, an extremely subtle something capable of switching the body from sickness to health, and vice versa. He called that something the 'Vital Force'.

It was this force which was responsible for the orderly and therefore healthy running of the body, and for coordinating the body's defences against disease. In fact Hahnemann thought of the Vital Force as a form of electromagnetic energy or vibration. If this coherent energy became jangled and disturbed by stress, poor diet, lack of exercise, inherited constitutional problems, or climatic change, illness would result. The signs and symptoms of the illness were the body's attempts to restore order.

Most of the ailments doctors see are 'acute' -they onset quickly, run a fairly well-defined course, and then clear up of their own accord with or without treatment. Hahnemann's rationale for prescribing homeopathic remedies in such cases was that they hastened recovery. The Vital Force, temporarily depressed, was more than equal to bouncing back. He discovered that in outbreaks of acute infection -measles for example - where the basic symptoms are usually the same for most people, the same remedy could be routinely prescribed for those afflicted; he also prescribed the same remedy as a preventive.

By contrast, 'chronic' or long-standing illnesses represent a series of minor victories and capitulations on the part of the Vital Force. Though relapses may be followed by remissions, the general trend is downwards. In his writing Hahnemann likened this process to a wearying civil war, with both sides alternately losing and winning battles. In such circumstances, the Vital Force stands sorely in need of mercenaries or, rather, correctly prescribed homeopathic remedies.

Hahnemann gradually re-established himself as a physician, using his new homeopathic methods. However it was not long before he realized that certain patients, whom he had treated for acute conditions, were returning to him complaining of new sets of symptoms. These often seemed to declare themselves after stressful events. As the years passed, it became clear to him that such patients were treading a descending spiral of health, despite intervals of feeling reasonably well. Were their episodes of acute illness a manifestation of some deeper malaise? In treating the symptoms of each acute episode, was he not repressing the fundamental, underlying problem or 'miasm'? 'Miasm', meaning 'taint', was the word Hahnemann used to describe these putative, deep-seated tendencies.

Hahnemann recognized various miasms, some of which we now know to be mediated by specific microorganisms which can indeed provoke repeated episodes of deepening illness if treatment is inappropriate or delayed; among them were syphilis, gonorrhea, tuberculosis, and cholera. Another was 'psora', which manifested itself in skin eruptions. Modern public health measures have made such taints less frequent, but the miasm concept continues to be useful and is much discussed among homeopaths. We now know that many bacteria and viruses, including those associated with measles, chickenpox, influenza, and AIDS, seem to create, in predisposed people, a vulnerability to all sorts of seemingly unconnected ailments. Depression and anxiety seem to underlie a host of conditions, from migraine to cancer. Hereditary conditions also have a miasmatic character. The task of the homeopath is to look for and recognize such disease patterns and attempt to treat them. By diligent research, mainly with sick people, Hahnemann developed remedies which seemed to work at the deeper miasmatic level. He also gave strict advice on the sort of diet and lifestyle his patients should follow - no perfumes or scented waters, no tooth powders, no snuff, sparing use of tobacco, no woollen underwear, no excessive bathing, no card playing, only occasional visits to the theatre, only moderate studying, and no madcap riding or cab-driving.

The first edition of An Organon of Rational Healing, the best-known and most comprehensive of all Hahnemann's writings on the nature of health, disease, and homeopathic healing, was published in 1810. He revised the book five times before his death in 1843, each time searching for greater understanding of the potency ot homeopathic remedies and the nature of the Vital Force. At the time of writing it is still in print.

During the nineteenth century Hahnemann's ideas spread quickly from Germany across Europe and then to the Americas, and also eastwards to Asia. Today homeopathy is well respected in some countries, notably in Britain, France, Germany, the Netherlands, Greece, India (where it is recognized and supported by the state), South Africa and South America, but mistrusted in others.

Homeopathy 'arrived' in Britain in 1832 when a Dr Hervey Quin began to minister to fashionable society from premises at 19 King Street in London's West End. Quin had travelled to Germany to consult Hahnemann on his own account and learned homeopathy from the Leipzig homeopaths. Later Quin became the first President of the British Homeopathic Society, founded in 1844. Thereafter, despite opposition from orthodox physicians, homeopathy steadily grew in popularity. Quin set up the first homeopathic hospital in London in 1850. The first royal patron of homeopathy was Queen Adelaide, consort of William IV, who, from 1835 until her death in 1849, was the patient of Dr Ernst Stapf, one of Samuel Hahnemann's closest colleagues. Three very distinguished homeopathic physicians have served the present Queen in the past, Dr John Weir, Dr Margery Blackie, and Dr Charles Elliott. Currently, Dr Ronald Davey holds this position.

In the United States the fire of homeopathy was lit by Dr Constantine Hering (b.1800). As well as formulating the Laws of Cure summarized below, he pioneered the use of 'nosodes', remedies made not from plants or minerals but from diseased tissue or from bodily secretions. In 1838 he and his colleagues used a homeopathic preparation of infected sheep's spleen to cure anthrax, at one time an almost certainly fatal disease.

(from "A family guide to homeopathy" by Dr. Andrew Lockie)