In the treatment of chronic non-venereal disease, Hahnemann found that the similar remedy was just as efficacious in removing the existing symptoms as it was in acute disease. But he also frequently found that while the patient night remain well for a considerably period, yet without adequate cause the same symptoms returned and were again removed by the remedy, though less perfectly than before.
This happened several times, until finally the remedy ceased to benefit. Being convinced of universality of the homoeopathic law of cure, he concluded that the ostensible disease could not be the whole, but only the active part of some much more extensive disease, or otherwise it would have been permanently cured.
Accordingly he endeavoured by careful examination of the history and progress of a large number of chronic diseases to discover all the ailments and symptoms belonging to this unknown primitive malady. He found that the majority of such patients had had the itch or some other cutaneous disease, such as eczema, herpes, tinea, etc., and that the symptoms of the chronic disease only began to manifest themselves after these had disappeared or had been removed by external treatment, and that the disease constantly tended to progress from without inwards-from the lesser to the more vitally important organs. Having now, as he believed, discovered the common origin of all the variously named chronic diseases, which he called psora, he chose from amongst the then proven remedies all such as were capable of producing symptoms similar to those of the miasm and advised that they should be employed in its cure.
Hahnemann believed that psora was always the result of direct infection, and probably this was the case originally; but now, according to Kent, all mankind is more or less psoric and the acute manifestations is only the taking on of a new load of the disease.
Many have rejected the psora theory, but practical experience teaches us to give by preference these very antipsoric remedies. This preference is not theoretical and is constantly subordinate to the general principles of homoeopathy. Dr. Rueter published what he believed to be the order in which the various organs were affected by psora, when not interfered with, but Kent is unable to confirm this sequence. Kent has observed that many diseases seem to be on the same plane, one member of a family having epilepsy, while others have insanity, cancer, tuberculosis, etc., the various organs being affected according to the circumstances of the patient.