On the Study of Homeopathic Materia Medica, Constantine Hering

The ordinary mode for acquiring knowledge of remedial agents – namely, merely by experience during practice – cannot be termed studying the medicines, and no directions are required for it.
Much time and labor may be expended in this mode without ever attaining a complete command of the medicinal agents. Many a homeopathic practitioner will find himself in the situation of walking on a treadmill – setting machinery in motion, without moving from the spot.  He who trusts solely the experience and observations of others, and thinks that by means of published collections of cases he will also attain accuracy in the selection of medicines in individual cases, or find a similar accuracy in his general views of medicinal agents – such a one constantly remains in a state of dependence, moving merely in the narrow circle which others have chalked out.
In another country amidst other customs, and at other times when a different character of disease is present – indeed, during the prevalence of individual epidemic diseases – he stands helpless and bewildered. His pockets are full of paper money that is not current there, and his hands are destitute of any available coin.
He who relies only on his own experience for knowledge of medicines can only attain a very limited understanding. His personal knowledge will be quite imperfect as regards individual remedial agents. If, perchance, one or other property appears peculiarly prominent, then the others will be but seldom or never attended to.
For example, consider the case of Aconite, which certainly is of frequent use in inflammations, but much more often in cases where no inflammation exists. Or consider Belladonna, which is frequently employed where it does not answer at all, and where Hyoscamus., Arsenicum., Bryonia., or some other remedy, should be used instead.
So understanding acquired only in this way will be imperfect, in fine, as regards our whole material-medica – because by this method the knowledge of materia medica cannot but always be very deficient. Only a small number of favorite remedies will be retained in memory – merely such ones as are known, or thought to be known, to possess some general determinate properties which render their selection easy.
In the greater number of cases that come under daily observation, these favorite remedies will very frequently be given where they are not of the slightest use. A number of remedies will be employed for merely single symptoms. And a large number will never be  prescribed at all.
In cases of a more serious and rarer description, even where the most careful research is employed, it is often all in vain. For sometimes many remedies seem to be equally indicated, so it is difficult to make a selection from among them. At other times no single remedy seems applicable. The more intimate our acquaintance with the medicines, the more seldom will such cases occur, and the nearer is the physician to the attainment of complete mastery of his subject. Tyros, who have merely glanced at the remedies, imagine that it is not possible to become acquainted with a single remedy which has such a vast number of symptoms – just as a country clown on coming to town is at a loss to conceive how the people know which way to go among such a number of houses. And yet, in the course of time, he himself finds no difficulty in doing this. Let us observe how this happens. It may help us a little in studying the materia medica. It is well known that a perso n who has been in many large towns can much sooner find his way than other strangers who have not. This is true without there being much resemblance between the towns. He must unconsciously have invented some method by which he becomes quickly at home in every new town.
In like manner, many homeopaths have unconsciously adopted a method of studying the material medica. Our present object is to make this method known.
Learning the materia medica “by heart,” would be a highly absurd plan – and not only impossible on account of the extent of the undertaking, but even if possible, still, utterly useless. In order to acquire a foreign language, what good would it do to learn the dictionary from beginning to end? One who could repeat the list of symptoms of a remedy in their regular order would not thereby possess knowledge of the combination of symptoms – and it is that knowledge of which we stand in need. In practice, we never make use of the whole range of symptoms, but only of a particular combination of a small portion of them. To the general symptoms of every form of disease, corresponding ones may be found in a large number of remedies – and every remedy contains the indications of a vast variety of diseases.
The Goal Of Study
Every medicine has its peculiar characteristic traits which must occur in each of the groups that are mentioned above. There cannot be the least doubt about this fact. But this only shows the goal from afar – a goal that we may reach by a careful study of the materia medica. Up to this time, only a few fragments of such characteristic traits have been discovered. Anyone may soon learn these by heart; but this can never be called studying the medicines. Properly speaking, the study of the medicines is rather the road to a fresh discovery of those traits which, during practice, are continually presenting themselves to us. And, at the same time, it will show the fallacy of many well-known dicta proceeding from some who have attained the reputation of great authorities through the indolence of others.
The homeopathic physician who knows little more than the characteristics of a few polychrest medicines (with the addition, perhaps, of a few other scraps of knowledge which he himself picked up) has only a one-legged stool – we may turn ourselves hither and thither, but it will fall to the ground if not sat on by someone with two legs. The homeopathic physician who knows no more than this is like a bad chess player – someone who only knows one or two methods of giving checkmate which he has learned from studying the fag ends of games played by celebrated players – put together with but a few other modes he has discovered himself. The master of the game commands all the pieces in every situation. He shows his skill even when checkmated, and, properly speaking, he never loses. Even though the physician at the bedside of the patient has ever so carefully compared a medicine with the case before him, this will tend but little to advance his knowledge of it. And such a comparison cannot be termed a study of the medicine, as it is only viewed in connection with the case thus before him.
To study a remedial agent is to attentively observe its symptoms and curative powers, without any reference to particular cases or particular diseases. It is to consider all its effects as connected with one another. All its individual symptoms are seen as separate parts of a whole. The many changes produced in the sensations by its action, which have been separately observed and collected together, are to be regarded as symptoms of one and the same artificial disease. They are seen to belong to one morbid picture. The proper mode of studying the whole materia medica consists of first making one’s self the complete master of a few medicines. Afterwards comes the mastery of those medicines most nearly connected with the first few, and so on. There is always a comparing of the new ones with those that were first studied. On this account, I call this the diagnostic method. After one or more families of nearly related substances have thus been worked out, the others follow much more easily. After pursuing the study in this manner with unremitting diligence for several years, then any new medicine may be made available after only one perusal. By carefully reading it over only once, so much remains impressed on the memory by the unconsciously acquired habit of comparison, that in a case of disease in which it is indicated, it is easily recalled to mind. He who can do this will not complain of the number of imperfectly proved medicines, or of the fewness of their recorded symptoms, while at the same time finding fault with the large number of symptoms presented by other medicines. Be the symptoms as numerous as they may, he can make himself be the master of them. Be they ever so small in number, he understands how to avail himself of them. He who has not the requisite foundation finds all additions to the materia medica a disagreeable burden. He shows by his discontent that he has not yet made himself master of the old matter. Methinks most of those who complain of our materia medica, are either totally ignorant of, or have but a scanty acquaintance with, our medicines.
Before we proceed to give specific directions, we shall:
1. Endeavor to defend the method we have proposed
2. Show how a single medicine is to be studied
3. Show how the others are to be connected to this one
A Defense Of The Method We Have Proposed
The assertion that one remedy must first be perfectly known, and that then the rest will be acquired with less difficulty, and still more easily the farther we advance, is founded on the principles and practice of mnemonics. This diagnostic method, indeed, appears to me to be the only practical plan of studying the material medica, or at any rate, the shortest and most direct way of attaining the end proposed. There are certainly two other possible methods. One is to learn what are called the principal symptoms of each medicine. The other is to study each substance by itself, and thus, all of them unconnectedly. A fourth and last method would be, not to study the materia medica at all. (Exempla sunt odiosa!)
To learn the so-called principal symptoms – e.g., to extract from an epitome like Jahr’s Manual, the most prominently marked sentences, and to get these off by he art – is the shortest way to practice. But, at the same time, it is the surest way to permanent mediocrity. Let him who is forced to make a trade of his profession, adopt this method. It will bring him soonest into the center of the woods. But let him not forget to secure at the same time a permanent possession. If not, he will resemble the squatters in the far west, who establish themselves without troubling their heads about their right to the soil. And when the buyer of the land chases them off, they remove to a distance, out of one wretched wooden hut into another. They barely support their existence by the scanty profits arising from ill cultivated ground, and the uncertainties of the chase. This superficial, unmeaning sort of life has charms for them. And their labors, together with those of the destructive wood louse, lighten the task of the settler. Those qualities that we at present term the principal symptoms of the medicines are, for the most part, unsatisfactory – nay, they prove an obstacle in the way of accurate individualization, and lead to carelessness. It is much more convenient to administer to patients a dozen homeopathic remedies according to this principle, than any plan of the old school. And one may, by such practice, be pretty sure, that by the end of the year a number of p atients will have recovered. These principal symptoms are, moreover, in many instances incomplete, and in many others perfectly false. They can only be known with certainty, and have their due value assigned them, by a careful study of the various medicines, having especial regard to their relations one with another. A mere acquaintance with these principal symptoms cannot be called studying the remedies. If we were in possession of a scientific arrangement of the materia medica, we might make it the basis of our study of the medicines. But at present, we cannot expect to construct anything satisfactory on such an uncertain and incomplete basis. He who seeks to study the medicines according to their symptoms, but each medicine separately and without instituting a comparison between them, will, with the very best memory, not advance far before forgetting what he had previously learned. The memory is incapable of retaining any thing but what is presented to it in connection with something else. An idea is easily brought to the recollection only when in connection with others.
We would remind him who has had no experience of the comparative method, either on himself or others, that acquiring a knowledge of the symptoms of medicines, is exactly similar to the mode in which the chemist, the mineralogist, the botanist, and the zoologist acquire a knowledge of the objects connected with their respective sciences. We should, therefore, set about it in a similar manner. Let it be considered what a multitude of signs are so perfectly at the command of the zoologist, that he can easily recall them to his recollection. Although no one is capable of giving a complete description of all animals, a repetition of all their characteristics “off the book,” as the saying is. Yet the zoologist can at once tell a new animal when he sees it. He can instantly determine to what class it belongs, and point out its particular characteristics. By merely looking at each animal, he already knows its characteristic peculiarities, or at least has no difficulty in discovering them. The homeopathic physician must do just the same with his medicines. Let it not be alleged that zoology and the other branches of natural science are things quite different from our science. It must be regarded and dealt with in exactly the same manner as the natural sciences.
Let it not be said that those sciences are so far advanced, and the system so perfect, that every thing connected with them is much easier. Suppose that our materia medica were at present as little advanced as a natural science – as zoology in the time of Aristotle. This should not deter us from regarding it as such, working it out as such, and studying it as such. By this means we should make as much progress in it as was then made in zoology – and that is a good deal in comparison to knowing nothing at all, or to wandering in benighted ignorance amidst a profusion of everything. I refer to those who possess a real knowledge of our materia medica, if that has not been obtained in the way I have just pointed out – and I doubt not that some now see that they have unconsciously obtained their knowledge in the same manner. There can only be one right way. But this may have been pursued without the individual being exactly aware of it himself, as has happened to those proficient in many of the arts.
When one remedy has been accurately studied, and the art has been acquired of classing others along with it according to their resemblance and of distinguishing the differences between them, then each subsequent group that is studied in a similar manner costs far less trouble. The result will be that he who has thus made himself master of a hundred medicines will require for the second hundred scarcely so much time and labor as he expended on the first ten. An increase of the medicines, therefore, ad infinitum, will never prove too much for human capabilities. Entomologists can easily acquire knowledge of a number of new insects. It requires little trouble on the part of the botanist to learn an endless succession of new plants. This they do by a speedy conception of the resemblances and differences among them – and the more practice they have, the easier it is. It may be urged that no such laborious mode need be adopted to acquire of one of the natural sciences, but that the general characteristics of the various classes are soon learned. In the present state of the natural sciences, all the relationships existing among the various classes and orders may be seen at a glance, and the study of them thereby greatly simplified. But, as we have not brought our materia medica to such a pitch of perfection – and from the short time of its existence, it has been impossible to advance it farther than it is at present – we must dispense with this simplifying glance. We must, however, on this account, follow the only path that leads to this end – laborious though it be at present. As the progress of inventions facilitates commerce and travel more and more, so the progress of science always lightens the task of learning what has been discovered. The same will be the case as regards the materia medica. Until that time comes, we must study the remedies as we find them. The time is, we hope, not far distant, when we shall be able to talk about the objects of our science in the same manner as natural historians do of theirs – when, like them, we may be able to give complete descriptions of these objects without touching upon unimportant information.
The time, we hope, is at hand when we shall know what is and what is not important in our material medica.
How Is A Single Medicine To Be Studied?
How can a remedy be studied, if the symptoms are not learned by heart? It can be learned through the same principle as the whole materia medica – by comparison. The symptoms of a medicine are to be read through carefully several times. This should be done from beginning to end, in the first years of study, with the pen always in hand. While reading, one thing or other is always to be particularly attended to.
— The First Reading —
At first attention should be directed to the organs in which the symptoms occur. It will be at once noted that many organs or tissues are particularly attacked. The organs that show the greatest number of symptoms are to be regarded according to their physiological relationship. In this, our previous studies are a great assistance, just as every physiological dogma, every hypothesis, even though false, is an aid to the memory.
Thus, the ear is said to be the peculiar organ of the osseous system. Therefore, when pains or nodes in the bones occur, I would observe attentively the symptoms of the ear. And, in this manner, many individual symptoms would appear more significant where connections exist. For instance, between the functions of the skin and kidneys, symptoms occurring in the one system will always call to our mind those of the other – whether those symptoms harmonize with or are opposed to one another. In our comparison, pathology will also be of use, and that will be so whether its theories are true or false. Thus, where symptoms referable to the liver occur, I would always compare the pains in the right shoulder, and vice versa. Where turbid urine is passed in small quantity, I would pay attention to the symptoms which point to the serous cavities. In doing this, for example, when studying Aurum, a number of symptoms would thereby appear more important, and consequently be more deeply impressed on my mind. And this remedy would occur to my memory not only in cases of effusion into the pericardium, but also in hydrothorax and ascites.
The important observation of Neumann – that diabetes is always preceded by a diminution in the activity of the kidneys – will be often serviceable in our consideration of the medicines. It will, for example, help to confirm the supposition that not much is to be expected from Argentum in cases of diabetes, and that this disease is mentioned in our repertories in connection with silver in this manner: Hahnemann, distrusted the alleged diuretic properties of nitrate of silver. Rather he ascribed to it powers that are exactly the reverse. But as far as I know, he does not adduce a single instance of its efficacy. While studying the symptoms of Phosphoric acid, we should call to mind the same observation that is also the recorded experience of its efficacy in several cases of milky urine – a kind of diabetes. In this manner we will see that a large number of the symptoms may be pathologically connected. During the first reading and comparison, the symptoms arrange themselves, as it were, into some sort of definite form. Thus we gain a collective impression of the whole that we retain in the memory, and recall to mind in all cases where the remedy is suitable.
— The Second Reading —
During a second perusal of the medicine, attention should be directed at the character of the symptoms. The former perusal was but a preparation for this step. The character of the pains in different parts should be compared – all pains or other sensations of the same, or a similar or a nearly related kind, that occur in different parts should be carefully observed. If this is done, it will be found, for example, that burning pains occurring frequently in various parts are not peculiar to Arsenic and Carbo-vegetabilis alone, but they also occur in Phosphoric acid and other substances. The mind will take a comprehensive view of them, and a complete picture of them will be retained.
At the same time, attention must be paid to the parts where these pains principally occur. Thus, we note whether the burning pains are more in the mucous membranes, or in the serous cavities, or in other parts. For instance, the burning pain in the case of Arsenic occurs most frequently internally, in the blood vessels. In the case of Carbo veg. pain is seen more externally, in the skin and joints. Both substances cause burning in the stomach and bowels, but Arsenic to a greater degree.
On the other hand, Carb. veg. causes much more in the breast – and so forth. In every substance where the same description of pain prevails, an attentive examination will show the characteristic features of each. We will soon discover that certain kinds of pain prevail in certain organs and tissues, e.g., tearing in the muscles, dartings in the chest, cuttings in the abdomen, pressure in the head, compression in the ears, boring in the bones, etc. But this we shall enter into more particularly in another place. This tends much to assist the memory, both directly and indirectly – the circumstance of an unusual pain occurring in any organ would be the more observed. A number of isolated symptoms are, moreover, more easily remembered in connection – when placed side by side.
For example, with respect to Aurum, it produces determination of blood to the head, to the chest, to the eyes; toothache from a similar cause; determination of blood to the legs; and many other symptoms that may be found to be connected with these.
An accordance of many of the symptoms of different organs may often be observed. Thus Caust. has sparks, flickerings, figures, an appearance of gauze before the eyes. Also, it has ringing,whistling; singing, chirping in the ears. On the other hand, Phosph. has points and spots, dark, black, and gray veils before the eyes; loud noises, buzzing, throbbing in the ears. After the moral symptoms have been arranged in groups, they may be easily impressed on the memory by comparing them with the corresponding symptoms of other organs. Thus anxiety, melancholy, etc., are to be compared with the symptoms of the heart and chest – or a weak, wandering, or obstinate state of mind, is compared with the frequently analogous symptoms of the digestive organs. And so forth.
— The Third Reading —
At the third reading, the conditions under which the symptoms take place should be noted. This must always be done pen in hand, even though Ruckert’s comparative work be employed. Doing it one’s self has great advantages, especially at the commencement of the study. One is exercised thereby; and all that has been previously learned is at the same time revised. It should be observed whether the symptoms take place on the right side or the left. If this has not been done previously, note at what part of the day they occur, when our pathological knowledge will be of great assistance to us. Observe in what attitudes, positions, during what motions, etc., the symptoms occur. Care should be taken not to indulge in vague generalities, such as “aggravation in the evening,” “worse on motion,” and the like. This is of small use in acquiring knowledge of the medicine, and it is an obstacle in the choice of it as a remedy. What we wish to know is, what symptom is aggravated in the evening or on motion. When possible, this symptom should be noted along with some connecting idea. Since Hahnemann taught us to distinguish between Bryon. and Rhus. by pointing out their opposite qualities – motion producing aggravation in the one case and rest in the other – it has frequently happened that too much value has been assigned to this circumstance in the choice of Bryon. Many other similar remedies are distinguished by possessing a similar pair of opposite properties – Bell. and Hyosc.; Nux. and Puls.; Chin. and Seneg.; Phos. and Nitr.; Sulph. and Con.; Carb. And Dros.. These along with many other substances bear the same relation to each other as Bryon. and Rhus.
Bell. has a far larger number of symptoms that are worse on motion than Bryon. – yet the symptoms that are worse on motion are perfectly distinct. As regards Bell., they occur mostly in the vascular system. With Bryon. they are chiefly to be found in the joints. The symptoms of the respiratory organs with Bryon. are not aggravated by motion. However, those produced by Bell. are decidedly so. One should be careful of coming to a converse conclusion. I mean to say, in the case of a remedy having a number of symptoms that are aggravated by rest, it does not follow that they will be ameliorated by motion, and vice versa. Thus Dulc. has many symptoms that are better on motion, but very few that are worse when at rest.
— The Fourth Reading —
The remedy may be perused yet a fourth time, with particular attention being paid to the combinations of the symptoms. The student may carefully observe what symptoms follow each other or occur simultaneously. However, the attention must have been previously directed to this point. When this was not the case, the student should seek to bring these combinations into connection with his former observations. Care should be taken not to adopt the notion that a remedy can cure groups of symptoms in a patient only if they occur in the order it produces them. A remedy is capable of curing groups of symptoms which it does not produce in the same combination at all – groups whose component parts were observed in a number of different provers, and frequently in quite a different order. From a pathological point of view, a special study of a medicine which compares it at the same time to different forms of disease may be useful after a thorough knowledge of the symptoms of the medicine has been acquired. Experience teaches us that a number of apparently perfectly different diseases, which are far asunder in pathological works, may still be cured with the same remedy. It would consequently be necessary to go over almost all diseases in connection with the remedy. This would be a great waste of time, and would not lead to a perfect knowledge of the remedy after all – our pathological systems are very far from being complete enough for this. It would be well, however, to compare the description of individual forms of disease, with many classes of remedies. Thus, for instance, those catarrhs which indicate Mercury and allied medicines are very dissimilar to those in which Arsenic, and medicines of its class, are efficacious.
How Other Medicines Are To Be Connected To This One
After a thorough acquaintance with one or more remedies has been gained in the above manner, the student must then pass on to others. The best course will be to go on next to those most nearly allied. The study of the second remedy is already somewhat easier. This is partly owing to the practice that has been had in acquiring knowledge of the symptoms, and partly because deviations from the character of the last studied medicine become more vividly impressed upon our mind. We must, consequently, have a very clear perception of these differences. They must assist us to attain a distinct idea of the peculiarities of the second medicine, as well as to stamp the knowledge of the first more forcibly on our memory. Therefore we must search for resemblances and observe differences in the more prominent symptoms – and in those that are more easily remembered, rarer, and more striking. I have called attention above, in the examples of Bryon. and Bell., Caust. and Phosph., Arsen. and Carb. veg., to the fact, that medicines which otherwise present great similarities in their symptoms, are yet widely different in certain respects. No regard needs to be paid to slight differences, nor even to whole groups of symptoms which one of the medicines has, and the other has not. No attention need be given to the fact that, in one case many symptoms are known, while with the other, very few are.
These factors may, however, demand our attention in cases where the different characters of the remedies are thereby marked – as in the case of Bell. compared with Bryon. regarding the moral symptoms, the effects upon the organs of the senses, the symptoms of the throat, etc. The differences sometimes lie in the combinations of symptoms, whereby they may present resemblances to perfectly different diseases.
More frequently, and much more clearly, these differences are expressed in the conditions under which the symptoms occur. These are often exactly opposite. Thus the very similar headaches produced by Bell. and Bry. occur in the former in the evening, in the latter in the morning. These differences are sometimes very subtle. For instance, most of the exacerbations of Acid. nitr. occur in the evening, but those of Acid. mur. are before midnight. Those of Acid. sulph. are after midnight, and those of Acid. phosph. are seen towards the morning. But all the acids present nocturnal aggravations. Symptoms of an opposite character are rare. But differences in nature are very frequent, as is the case in the gastric symptoms of Bell. and Bry., Bry. and Ant. crud., Ant. crud. and Ipec., etc. Symptoms in opposite situations are more frequent. Thus, similar symptoms are often distinguished by occurring in one case on the right, in another on the left side – as happens with Arn. and Lach and others. The catarrhal affections of Bell. are distinguished from those of Dulc. in that those of the former occur more in the mucous membranes of the head and neck – in the region of the carotids – where those of the latter occur more in the chest and abdomen – in the course of the descending aorta, etc. Beginners are apt to attend too much to specialties when making these comparisons. This over attention becomes a very laborious task, and is apt to lead to a total abandonment of the study.
There is, however, no better way of avoiding this error, and of learning how to make one’s self quickly the master of the generalities, than to surmount undauntedly the laboriousness of the beginning.
On a second comparison, the mind is more accustomed to the work. According to the talents and previous acquirements of the student, will it be a longer or shorter time before he comes to be able to complete the comparison of two remedies in a few days. We must caution those who pay too much attention to specialties not to be so very minute, but above all things to seek for points of crystallization. We must point out to those who are disposed to be superficial that important discoveries for practice may be made by a careful comparison. The comparisons may be very easily made by means of Ruckert’s systematic tables. The remedies to be compared are to be sought out in each division, their symptoms carefully read, and the result committed to writing. A separate column is assigned to each medicine. Those symptoms which both have in common should be written in the middle. When there is only similarity, the sign of similarity should be placed in the middle between them. Where opposites, or well-defined differences exist, they should be distinguished by an interposed arrow, etc. It cannot be expected that anyone, least of all a beginner, will compare every remedy with every other. The student should select remedies for this purpose that he considers to be analogous, and which are known to possess important properties. All remedies that are closely related by the source of their derivation, must also be related with respect to their symptoms. All that are chemically allied must be so medicinally. Those possessing similar odors – as are Phosph., Ars., All. sat., Asaf., and Bufo. – must possess resemblances in their symptoms, etc. The chemical preparations may be arranged in natural families, according to one or other system. Those nearly related are thus compared, e.g., Sulph. and Phosph.; Chlor. and Iod.; the carbons and Graph.; the oxygenous acids, Nitr. ac., Sulph. ac., and Phosph. ac. are compared with each other, and with the hydrogenous acids, Mur. ac., Hydrocyan. ac. Further, Sil., Alum.; the carbonates of potash, soda, and ammonia; Bar. and Stront.; Calc. And Magn.; the muriates of soda and Am., Bar. and Magn. The acetates of Cupr., Ferr., Plumb., Mang.; the metals Aur., Plat., Stann., Arg., and Zinc. Interesting comparisons may be made between Phos. ac. and Phos.; Sulph. ac. and Sulph.; as also Sulph. and Hep., Hep. and Calc.
Medicines From The Vegetable Kingdom
Among medicines belonging to the vegetable kingdom, those which may be compared as being nearly allied, are:
Anac. and Rhus.
Bryon. and Coloc.
Ind. and Tong.
Op. and Chelid.
Spig. and Menyanth.
Viol. od. and Jac.
Thuya. and Sabin.
Coff., Ipec., Chin.
Colch., Verat., Sabad.
Euphr., Dig., Grat.
Lauroc., Prun. sp., Amyg. am.
Led., Rhod., Nux vom., Ign., Oleand.
Arn., Cham., Cin., Leont.
Asa., Cic., Con., Aet., Phell.
Bell., Caps., Hyosc., Stram., Tab., Verb.
Acon., Clem., Hell., Puls., Staph., Ran. bulb., and Sol.
The cryptogamous plants, Agar. musc., Bov., Lycop., are too remote from each other – and yet their symptoms are much more similar than those of the more nearly related families of Solaneae and Ranunculaceae. Sec. can only be judged from from the cures it has effected – the symptoms of it derived from epidemic diseases are not to be relied on.
It is worthy of observation that the differences of those substances which are allied in their origin lie principally in the conditions of the symptoms; whereas those substances nearly connected by the similarity of their symptoms alone, agree merely in single departments of symptoms, but in others have quite a different character and seat. Families of substances that are related only in their symptom may be formed from such medicines as may be employed with advantage in succession – or which serve as antidotes to each other. In the present state of homeopathic literature, the formation of such families is a very hazardous experiment. But they are of much greater practical value than those formed from their natural affinity.
It is perfectly evident that substances that have a similar origin must produce many similar symptoms. Our business should be to search for the differences, in order to avoid confusion. When, however, minerals, plants, and animals, widely different from each other, produce similar groups of symptoms, there must be some deeper reason for this. It must indicate the similarity of the medicinal to the natural diseases. Such allied medicines are in general the best antidotes of each other. However – as must happen from the rules laid down above – among the metals that form several families, there are antidotes which are never found among those that are nearly connected, but always among those that are widely separated. Thus it follows that Sel., Ars., and Am.; Plat. and Argent.; Stan. Plumb., Zinc. and Nic.; Ferr. And Mang. do not antidote each other. But the metals Plumb. and Plat.; Ferr. and Ars.; Am. and Merc. do.
Among plants there must be antidotes in each family, and perhaps in each genus. There are, indeed separate parts in every plant and animal, which seems to have a power of neutralizing the effects of the others. Other homeopathic writers have pointed out a close connection between the two naturally allied substances Nux. and Ign., on the one hand, and the symptomatically allied Puls. – to which may be added Cham., Coff., and Caps. We may, I think, also reckon Ambr. among these. Another family is Ars., Verat., Ipec., Asar., to which we may add Ferr. and Chin.; perhaps also Staph., and Ac. sulph. Sulph., Calc., and Lyc. are well known as doing well in succession – to which may be joined Led., and in another point of view, Therid.
One of the most remarkable and beautiful families is Hep., Merc., Bell., and Lach. Between these and those allied to Arsen., may be placed Phos. ac. and Carb. veg., and those related to them, as also Cupr., and on another account Aur. Anyone who has thoroughly made himself master of two or three families, and then from time to time makes a comparison between two remedies which appear to him to be related – and between which he has frequently needed to make a most accurate choice in practice, as for instance, Sulph. and Ferr.; Phos. and Caust.; Ars. and Carb. v.; Bell. and Bry.; Bry. and Rhus.; Rhus. And Dulc., etc. – this homeopathic doctor gradually obtains such an extensive basis of knowledge that all the rest of the remedies are acquired without difficulty. If a crystal of salt is suspended in a saturated solution of the same salt, the most beautiful crystals collect upon it.
So, one who is acquainted with a large number of medicines in the above manner, can thereafter compare every medicine with every other in a very short time – and without many quires of paper. This must happen before our materia medica, which ought to belong to the natural sciences, can be looked upon as one of them.

from “Wirkungen des Schlagengiftes”
Allentown und Leipzig, bei C. Kummer, 1837
British Journal Of Homeopathy
vol. II 1844 no. 7