INTRODUCTION PRISMA MATERIA MEDICA points out parallels and similars between homoeopathic drug pictures and the substances from which they are derived. In addition, it wants to clarify and illuminate lesser known aspects of smaller polycrests. Much has changed since the time that Hahnemann and Hering undertook their provings, not only regarding the criteria of provings but also in terms of the information on substances. We have much more information at our disposal today and it seems foolish not to use all available resources to build a better materia medica. Since it is our sole duty to heal the sick, to paraphrase Grimmer, "we cannot afford to ignore intelligent help from any source so long as this aid available is based on law and common sense." The hot debate raging currently over the question whether homoeopathy is scientific or not, appears to make the doctrine of signatures its main scapegoat. In faithful imitation of Hahnemann, who considered it the "folly of the ancients", the doctrine of signatures meets with fierce opposition, being depicted as the folly of present-day homoeopathy and a major danger to scientific homoeopathy. The word 'signatures' has indeed a medieval ring to it and may partly explain the sharply contrasting opinions about it. However, the question remains whether signature is alien to homoeopathy. Hering observes that this very ancient doctrine "has much to recommend it on the grounds of similia" and Clarke states, in the introduction to Magnesia carbonica, that "it is often found that the physical characteristics of substances correspond with their dynamic influences." Consequently, in the introduction to Magnesia phosphorica, he remarks that "there are other means besides provings of finding the keynote symptoms of remedies." Clarke touches here upon a delicate issue, for the common assumption that drug pictures derive from provings shows to be erroneous if we closely study the materia medica. Approximately fifty percent of it comes from clinical cases. We seem to be so devoted to quantification and to explanation in terms of cause and result that we tend to overlook the significance of meaning, connection, and analogy, writes Twentyman in the British Homoeopathic Journal of Oct. 1974. By believing that homoeopathy depends on the symptoms produced in provings and on the symptoms in which disease manifests itself, we may cut ourselves off from natural science. Based on law and common sense, natural science constitutes the modem version of the ancient doctrine of signatures and here much information can be found about the peculiar features of substances. New information, updated information, additional information, and information to confirm or correct existing drug pictures. It goes without saying that a drug picture should relate to the substance from which it is derived, at least partly, if not entirely. On the other hand, the subjective personal factor can not be excluded in the production of symptoms. Hahnemann designed his provings in such a manner that they, he thought, would reveal the pure effects of substances. His sole aim was to find the "proper action of the medicines on the vital force", which he termed primary action. This could best be achieved with moderate doses of a substance because such experiments "almost never lead to a reaction of the vital force of the organism - secondary action." In Habnemann's view, substances can only cure homoeopathically the morbid states produced in their primary characteristic action. Hence, Hahnemann does not accept secondary actions as being part of drug pictures. Thus, the "observant physician" should, for instance, " refrain from its employment [of Stramonium] in cases where the patient is already suffering from ailments resembling those of the secondary action." Scientific homoeopathy claims this rule to be its basic principle. The appropriateness of I what can cause can cure' as the basic definition of homoeopathy is, however, highly debatable. Is a division into primary and secondary possible at all, and if we wish to make such a division, how are clinical symptoms then to be regarded? Moreover, it will necessitate an explanation for the appearance of opposite symptoms in provings. For example, Hahnemann's proving of Bryonia yielded constipation as a local keynote, whereas in Mezger's Bryonia proving mainly diarrhoea was observed. Hahnemann's statement that "Opium is almost the only medicine that in its primary action does not produce a single pain" is inconsistent with the results of other provings, for example those conducted by Jorg in the 1820s, where frequently pains occur within minutes of the intake of Opium, even in its crude form. And so on. In addition, provers participating in several provings will tend to produce an almost identical set of symptoms. Such symptoms belon- to their personality rather than to the proving substance. Should we consider them as primary or as secondary? The most notorious example is Langhammer - a member of Hahnemann's provers union - who, irrespective of the proving substance, invariably comes up with symptoms such as "silent, reserved disposition", "want of trust in people" and varieties on these themes. No prover involved in a number of provings will be free from what may be called 'the personal factor'. Even Hahnemann himself did not escape from it, since he, for instance, produced five times the 'delusion of being unfortunate' in as many provings. There is much to say for Clarke's opinion that "whether an action is 'primary' or 'secondary' depends on the prover or the patient." Since primary and secondary represent the opposite poles of a polarity, it would make sense to study which polarities are active in a substance or activated in prover or patient. Opposite poles have in common that they are part of the same polarity [issue]. Can it be so that the substance contains the issues and that the prover or patient, unconsciously or consciously, decides at which pole of those issues he is going to be? Thesis or antithesis, hypo or hyper, uncompensated state or compensated state, psora or sycosis, flight or fight, fear or fascination, no matter how we label this mechanism, it all comes down to the same idea of polarity. Investigating the inherent issues [characteristics] of substances consequently provides other means of finding the polarities of remedies. Such an investigation requires a serious approach. That we, according to Clarke, cannot fail "to notice the curiously toad- like aspect assumed by the subject" during a characteristic epileptic seizure may help to understand the importance of Bufo in the treatment of epilepsy, but, on the other hand, represents only one aspect of the doctrine of signatures, and a rather superficial one for that matter. To discover the characteristics of a substance, we should do a proper consultation with it, as we do with patients. 'Interviewing' a substance means gathering all possible information, from every available source, about that substance. Bringing the information back to its essential features is the next step, corresponding with analyzing the material provided by a patient. Remarkable correspondences / parallels may reveal themselves. For example, members of the Nightshade family [Solanaceae] that contain tropane alkaloids, such as Atropa belladonna, Datura stramonium, Hyoscyamus, and Mandragora, are known in botany as long-dayplants.- they flower only if the light periods are longer than a critical length. In addition, they require a certain amount of sunlight for the optimal development of their typical constituents [tropane alkaloids]. The right ratio of light - darkness is one of their essential issues. In relation to the fact that Veratr-um album is an inhabitant of mountainous regions, it is intriguing to note that the levels of the plant's toxic alkaloids depend on the height on which it grows: above a certain height the poisonous levels decrease. Apart from providing numerous instances of such correspondences, PRISMA MATERIA MEDICA contains the results of many non-homoeopathic experiments which may extend or improve existing drug pictures. The 'provings' of Bufo are simply ridiculous, to put it bluntly. However, modem research and experiments with toad poison open up new perspectives. Ditto with other substances of animal, mineral, or vegetable origin. Another advantage is that prejudices can be counterbalanced by more accurate observations. This is of special interest when such prejudices are implied in the materia medica. As with the toad, the bushmaster [Lachesis muta] appears to lend itself readily for such purposes. In his studies of Homoeopathic Remedies, Gibson points out that there are correspondences between the character and behaviour of the "dreaded surucuccu snake of South America" and the characteristics of the Lachesis 'subject'. Following older descriptions in homoeopathic literature, the snake is depicted as "an aggressive brute, attacking even human beings without provocation". The authoritative work Snakes: The Evolution of Mystery in Nature, by biologist Harry W. Greene, however, shows that the bushmaster hardly ever bites, partly because it is unusually timid and partly because it is strictly nocturnal and doesn't come around human habitations. Of some 8,300 snakebites recorded in South America for the years 1902-1965, only 16 were by the bushmaster! According to Roger Caras, in Venomous Animals of the World, the bushmaster is slow to take offence and of a truly placid disposition. He illustrates this with a story about some people who "were dragging a large bushmaster along a dusty road on a leash they had fashioned from a shoelace. ... Periodically they would stop and push the reluctant snake along, for it was not very good about being walked like a dog." Completion and addition are more good reasons for including data from natural sciences into the homoeopathic materia medica. A few examples. The recently discovered connection between boron and osteoporosis puts the Borax symptom 'fear of failing' into a new perspective. The mind-picture of Manganum reveals hardly any specific symptoms. A phenomenon known as 'manganese madness'- which even has been connected with BSE [mad cow disease] - is not included. The bite by the black widow spider [Latrodectus mactans] may cause a syndrome named 'latrodectism', much of which is missing in the materia medica. Although blonging to entirely different plant families, Plantago [plantain] and Euphrasia [eyebright] have the presence of the rare biological substance aucubin in common. Aucubin is the main active ingredient of 'anti-smoking compounds'. Plantago is in homoeopathic literature mentioned for that purpose - remedies to increase disgust for tobacco - but Euphrasia is not, despite the fact that two provers developed an aversion to smoking. Demographic studies have demonstrated the severe mental and physical effects of ergot poisoning I Secale cornutum]. Much of the mental symptomatology is not included in the materia medica. The psycho-active properties are thought to be related to the alkaloid lysergic acid, which naturally occurs in the fungus and from which LSD is derived. Placed against the background of medieval beliefs, the alleged bewitchment by the devil would seem intensely 'bad trips' or, more accurately, acute schizophrenic attacks [which LSD is known to produce]. Structure of the book Every remedy is introduced with a quip or a quote, ranging from deadly serious to light-hearted. Taken from every available source, the SIGNS section contains [summarized] information about the substance from which the drug is derived. Sources are documented. Collecting the information for the SIGNS section was like making a journey through the colourful world of books, articles, internet texts, and websites. And yet there is still so much to discover. The section MAIN SYMPTOMS is a revised and enlarged version of the 'Leading Symptoms' in Synoptic Materia Medica 1. Quotes are indicated by a black dot ; quotes include the exact phrasings of proving symptoms, as well as clinical symptoms, fragments of cases, contemporary concepts, and correlations. The symptoms comprising the RUBRICS section are taken from Synthesis, Edition 7.1. By going through the proving reports in Hughes & Dake's Cycloppaedia of Drug Pathogenesy, I came across symptoms which have been overlooked or, in my opinion, misinterpreted. These are added or corrected, respectively. References are given for all additions; additions without a reference are mine.