Now that the salient points regarding the Psora – theory have been discussed it remains to pronounce our verdict on its validity. It is our considered opinion that Hahnemanns Psora theory is not wrong – rather throws a flood of light on some obscure regions in the field of medicine – but it is tainted, to a certain extent, with some unwarranted assumptions, dogmatic assertions, obscurity of conceptions, undue generalisations, incomplete formulations and arguing in a vicious circle. It is to be noted that since the first publication of Hahnemanns views on the nature of chronic diseases we do not find a single homoeopathic physician of repute (excepting his two disciples Stapf and Gross) who endorses Hahnemanns views in toto.
Another fact is also to be borne in mind that the basic principle of Homoeopathy i.e., the Law of Similars, does not stand or fall with the Psora – theory. It is very aptly remarked by Dudgeon, in his “Lectures on Homoeopathy” that “it is not a doctrine coeval with the promulgation of the Homoeopathic principle, but an after – thought, not developed until thirty – two years later and as we might give credence to it, like Autenreith, Schonlein and others, without being homoeopathists, so we might reject it without losing any of our claims to that title”.
Some are of opinion that there can be nothing more paradoxical than the fact that Hahnemann the promulgator of the medicine of Experience should end in being an enthusiastic sponsorer of a highly speculative theory like the Psora theory. Some note that it is remarkable how extremes meet in Hahnemanns mental organisation. In his homoeopathic law, we have the principle of extreme individualisation, whilst the Psora – theory is an illustration of the opposite extreme of generalisation. But this is not the only instance of swinging of the pendulum to the other extreme by Hahnemann.
Hahnemann had before this in his “Coffee – theory” of Chronic diseases, which he retracted afterwards in favour of “psora”, exhibited the same tendency to generalise and the incubation period of his Coffee – theory, curiously enough, corresponds almost precisely with that of his Psora – theory. He tells us the latter occupied his thoughts for about twelve years before he gave it to the world, and we have evidence from his writings that the Coffee – theory engaged his attention for a nearly equal period.
Thus we find in his “Friend of Health” published in 1792, various hints as to Coffee being at the root of many chronic diseases and his famous essay on the manifold hurtful effects of this common beverage was published in 1803; and we have seen that the germ of his Psora – theory which was finally promulgated in 1828, is discoverable in an essay he wrote in 1816.
The following are the postulates involved in Hahnemanns Psora- theory which we are required to believe:
1. That seventh – eights of all chronic diseases are the consequence of an infection with a skin disease, that has been driven off or removed by external treatment.
2. That his skin disease is identical with what we call itch, though it presents itself under many different forms.
3. That every infectious chronic disease is scabies or a degeneration of it.
4. That none of these seven – eights of all chronic diseases are curable, save by the use of a certain set of medicines that were mostly unknown or unused before Hahnemanns time, consequently that no such chronic diseases were ever cured before the promulgation of his doctrine in 1828.
5. That itch, properly so – called, and all the varieties of skin diseases Hahnemann includes under that term are only safely curable by internal remedies, and that their treatment by external remedies is fraught with the greatest danger to the patient.
Let us now proceed with a critical examination of the above items, one by one.
With reference to the first item it sounds very dogmatic to assert by one individual observer, however vast his personal experience might be, about the relative percentage of incidence of different types of diseases that human flesh is heir to.
With reference to the items No. 2 and 3 regarding the origin of chronic diseases from itch eruptions an exhaustive discussion was attempted previously. Here my conclusion wholly tallies with that of Dudgeon who wrote thus: “I think it must be obvious to all who have carefully studied the evidence Hahnemann adduces in support of his this doctrine, that he fails most signally in proving his point.
In the first place his diagnosis of the disease is of the loosest. He treats with contempt the division of skin disease into different species, so carefully drawn by the dermatologists; and in the ninety – seven instances he takes from allopathic writers of the production of a serious disease after externally treated psora, he includes all manner of skin diseases, many of which have not the slightest claim to be considered of a scabious nature.
Every cutaneous disease that itches, and when scratched burns, more especially if it can be suspected of being contagious, is identical with itch, according to Hahnemann. This is one more instance of Hahnemanns mental trend of undue generalisation which does not stand scientific scrutiny. Thus Otto Lesser aptly remarks in his Text – book of Homoeopathic Materia Medica: “Although one does not have the impression of a loquacity senilis, there is the ring of incompletely formulated mental sequences.
Only in a type of summary has Hahnemann finished these thoughts and then, capricious as he was, attributed itch as the cause of psora and therewith the majority of chronic diseases. He gave the most unimportant aspect of the entire psora – theory an excessive accent and there was and still is the danger that the good is cast away with the bad, that is, in this instance the theoretically and practically important thoughts on the relations of chronic diseases remain unconsidered.”
Many eminent Homoeopaths viz. Dudgeon, Hughes, Burnett etc. openly declared that they have never succeeded in the very slightest degree to cure itch proper or scabies according to Hahnemanns directions. The undue emphasis on the itch laid upon by Hahnemann may be due to the fact that at the time when Hahnemann thought of Psora – theory the whole of Europe was infected with itch to an unprecedented extent, in consequence of the great military operations all over the continent.
Though Hahnemann brought his encyclopedic knowledge to bear on the subject of itch – theory he failed to establish the causal relation between suppression of itches and the incidence of chronic diseases. Mere succession of phenomena is not logically enough to establish a causal relation between a preceding and a succeeding event.
According to some it would have been a great boon to pathological science had Hahnemann, in place of confounding all skin diseases together under the one head Psora or itch, carefully individualised all skin diseases and endeavoured to discover the particular internal diseases with which it is probable each is in a certain measure connected.
Further Hahnemann distinctly alleges that every person affected with a non – venereal chronic disease must, at one period of his life, have had the itch at one time or another, however slightly; and he argues in a most vicious circle on this point.
Certain medicines, he says cure those chronic diseases that we meet with in persons who have avowedly the itch, we may, nevertheless, infer that they have at one time had the itch, because we can cure then with antipsorics. What wonder, after such a style of argument on the part of the Master, that the disciple Attomyer should say “we dont need to ask if the patient has ever had itch; psora is self evident.”
Thus the psora – theory, viewed as a mere theory of the origin of the most of chronic diseases form itch is by no means always capable of being proved, and the occurrence of the itching of the skin or eruptions thereon be regarded as a proof of the previous existence of itch.
With regarded to item no. 4, we find that when Hahnemann talks of the utter inefficiency of the treatment of chronic diseases he is guilty of great exaggeration, a fault which he frequently commits; for there is no doubt that chronic diseases were cured by Hahnemann himself, as we learn from many cases detailed in his “Lesser Writings” before the discovery of the psora origin of diseases and before he knew a single so – called antipsoric medicine.
With regard to item no. 5 we must give credit to the phenomenal clinical intuition of Hahnemann in discovering a reciprocal relation between skin lesions and affections of internal organs and tissues; and that any attempt to treat the cutaneous part of the disease is merely a palliative one with all the irrationality, difficulties and dangers inherent in the palliative method of treatment.
With regard to obscurity of conception we have dwelt at length over the problems of connotation and denotation of the terms like Infection, miasm and psora. We have also pointed out how it was impossible for Hahnemann to fix the specific denotations of various miasms as microscopy was rudimentary and the bacteriological science was as yet undeveloped.