While the qualitative specificity problem can be approached through groping animal experiment, a solution based on this procedure presents almost infinite difficulties. Even if one accepts as necessary the limitation of animal investigation to etiologically definite diseases with objective symptomatology (likewise separated from causes), then within this limitation a therapeutic animal investigation can be valued only as a schematic preliminary for clinical study; schematic because at best it can be considered as the general type of bacterial defense for the animal organism, but not the temporal and individually variable defense functions in man.


Here is the starting point of homoeopathy. With the postponement of the goal from the etiologic to the entire comprehensible symptomatology it steps beyond the naturally given limits of animal investigation. It considers the specificity problem directly in man. Through the introduction of a second equation it practically determines, so to speak, the X, the specific relation of drug to patient. It is a genial solution if one first answers by observations made on healthy man the question which of the defense functions is a single medical agent able to stimulate? The symptoms with which a man reacts to a drug make the qualitative specific connections available. So we have an equation of cure. The sick man indicates to us the nature of his defense functions in symptoms. In order to stimulate them we need only to compare the signs and to take them as indications. This leads to a solution which can satisfy us practically. Theoretically, we might solve the individual equations by themselves: that is, discover the defense functions in each case of disease in all details of how and by what and likewise the intermediate processes with which the healthy organism reacts to every medicinal substance. But practically we cannot expect the complete solution of this infinite task but we can use with advantage the available immediate observations as indications, as measuring sticks for determination of the suitability of the agent.


It is exactly the inevitable gaps of all animal experimental drug investigation which are filled in by the homoeopathic method. Further, it is an experimental and therefore fundamentally scientific method. For it places man in the center of natural interrogation from the start. Through the drug proving on healthy man it gains two heights; first, the avoidance of the sure of error of transference from animal to man and moreover the extremely important supplementation of investigative procedures by all the data which are obtainable only from man with the assistance of his capacity for communication, the so called subjective symptoms. The well-known source of error, the unreliability of these symptoms, is not able to neutralize this advantage nor to reject the method. The meaning of homoeopathic provings on men can be perceived in the humanization of the materia medica. The difficulties and limits of this attempt we shall consider further but the necessity of such a supplement of all materia medica will depend upon them. This theoretic advantage, moreover, becomes practical only through the therapeutic orientation of homoeopathy; it is primarily a stimulation therapy, it consciously utilizes the earliest, most active phenomena of the organism against a stimulus. And for this purpose the subtle, functional drug reactions, the individual indicative human reactions, serve far more than the signs of disturbance in any organism, animal or man succumbing or overcome and passively forced by a stimulus. We assume here certainly with right that the stimulus to an increase in performance is the high goal of therapy rather than the coercion which proceeds to functional incapacity.

Here a remark should be made whose basis will later become clearer. It is a mistake of the meaning of homoeopathy when Bier3 holds an acute mass investigation as narcosis with ether as an especially valuable drug proving in the sense of homoeopathy. The stormy course of depression of definite functions makes such an experiment hardly useful for supporting a stimulation therapy, regardless of whether it has been repeated a thousand times. Only the excitation of secretion of the upper air passages up to inflammation and the stage of intoxication are the paltry yield of active symptoms in this description, paltry because they are not sufficiently precisely described in their development and their characteristics and because the rapidly occurring paralytic symptoms are not described. Bronchitis and intoxication can be produced by many drugs. The homoeopathicity of ether to bronchitis is not to be doubted. But it is exactly here that the important individualizing characteristics for a differentiating therapy are lacking.

Briefly, the drug proving in man must be so arranged that the question What expressions of life is this medicinal substance able to excite or increase is answered with the uttermost exactness and differentiation, that is, which will respond as characteristic attributes to this one substance. It is exactly for this reason that homoeopathy has been occupied over a long period with continuous drug proving. What has been derived from it we shall examine more closely.


First, we must prove the therapeutic meaning of this humanized materia medica in another direction which is promoted in homoeopathy: that these medicinal effects on the healthy can be employed in the same sense to the patient. It is generally known that this transference occurs with the help of the simile rule, also through the comparison of the symptoms of the patient with the symptoms of the proven drug. Thereby nothing more is presumed than that: (1) the symptoms and signs afford the living defense of man against an injury (not once but throughout); (2) that the drug provings likewise furnish such defense symptoms; (3) by the concurrence of many symptomatic signs it is plausible that the defense functions in patients are involved and increased in the same way as they would be stimulated in the healthy. Thereby the increased sensitivity in the patient should find consideration in the dose. More than a great probability cannot be expected as in any biologic measure; also more is not aspired for in such balanced therapy, by the adaptation of the drug stimulus to the patient by symptomatic comparison. But to increase this probability evermore is to a high degree a matter of good drug proving, good art of observation on the patient and the ability to recognize the situation again.


The new meaning of homoeopathic materia medica brings with it a directness in the representation of drug action which, due to its simplicity, at first seems unscientific. But it is at least just as scientific to say at first what is, that is, to describe exactly, as to say, what one thinks about these manifestation at the time. Particularly when the simple factual description is neglected in comparison to mentally tracing back to common causes or by conception generalizations, there exists the great danger because at times modern theoretic conceptions must be completely given up in the use of drugs. But the causal or analytic way of investigation has become the flesh and blood of scientific investigators, so that the limits for recognition are stepped over by an excess of premature deductions, of very premature hypotheses, to the disadvantage of obtaining natural control. On the other hand I may remark here that the newest employment of scientific theory proceeds so that the goal of scientific perception is ultimately the revelation of what actually is and to see again in a type of description. I may mention here especially Rosenzweig and H. Herrigel. Indeed, it is not denied that the causal investigation in its place is also an important source of scientific recognition. It can be further developed within its limits for the control of natural processes. For the avoidance of disease, for example, this method of thinking may be regarded as sovereign. And exactly for the peculiar task of therapy, the influence of tendencies of the total organism or a part, this mental procedure proves fruitful. Scientifically the search down to the ultimate manifestations of the human organism and its exact description also is just as exact as the search for a causal explanation. In one by comparison to a therapeutic method, which homoeopathy is, the preference is given to the immediately observable and exactly described manifestation over all deductions on disease or organ conceptions but those given from the start. That the new orientation of thinking here conquers a practically new land I might consider a most significant point in regard to homoeopathy.

We are also convinced that it is entirely rational if the homoeopathic materia medica utters the speech of the sick patient as exactly as possible, that is, describes as exactly as possible by mimicking the patient. This is so much the better for the recognition of the symptom observed in the patient and finding the similar in the representation of the action of the drug. Further, one need not be frightened by the preponderance of merely orally reported, so called subjective symptoms. They are at once the most subtle symptoms and also the most subtle indications which can be evaluated.

Otto Leeser
Otto Leeser 1888 – 1964 MD, PHd was a German Jewish homeopath who had to leave Germany due to Nazi persecution during World War II, and he escaped to England via Holland.
Leeser, a Consultant Physician at the Stuttgart Homeopathic Hospital and a member of the German Central Society of Homeopathic Physicians, fled Germany in 1933 after being expelled by the German Medical Association. In England Otto Leeser joined the staff of the Royal London Homeopathic Hospital. He returned to Germany in the 1950s to run the Robert Bosch Homeopathic Hospital in Stuttgart, but died shortly after.
Otto Leeser wrote Textbook of Homeopathic Materia Medica, Leesers Lehrbuch der Homöopathie, Actionsand Medicinal use of Snake Venoms, Solanaceae, The Contribution of Homeopathy to the Development of Medicine, Homeopathy and chemotherapy, and many articles submitted to The British Homeopathic Journal,