This section is from the book "A Compend Of The Principles Of Homoeopathy", by William Boericke. Also available from Amazon: A Compend of the Principles of Homoeopathy as Taught by Hahnemann.
1. All chronic diseases are so inveterate immediately after they have become developed in the system, that, unless they are thoroughly cured by art, they continue to increase in intensity until the moment of death. They never disappear of themselves, nor can they be diminished, much less conquered or extinguished, by the most vigorous constitution or the most regular mode of life and strictest diet.
2. Psora is the oldest, most universal and most pernicious chronic miasmatic disease. Existing for many thousands of years, its morbid symptoms have increased to such an extent that its secondary symptoms have become innumerable.
3. The ancient nations designated psora as leprosy, by which the external parts of the body became variously disfigured, and during the middle ages the Crusaders spread it over Europe. Cleanliness, increased refinement and more select nourishment succeeded in diminishing the disgusting appearance of psora so as to reduce the disease, towards the end of the fifteenth century, to the ordinary eruption of an itch. But about this time, 1493, the second contagious chronic disease, syphilis, began to raise its fearful head.
4. During the first centuries of leprosy the patients, though they suffered much in consequence of lancinating pains in the tumors and scabs, and the vehement itching all around, enjoyed nevertheless a fair share of general health, for the obstinately lasting eruption upon the skin served as a substitute for the internal psora, and furthermore the leprous patients were kept apart from human society and thus the contagion remained limited and rare.
5. But the milder form of psora, in the shape of an itch, infected a far greater number of people, and the itch vesicles being constantly ruptured by scratching and their contents spread over the skin, and those things which had been touched by such patients, psora became the most contagious and most universal of the chronic poisons. Though this eruption by its easier concealment may attack many persons, still the essence of this reduced psora remains unchanged, and being more easily repelled from the skin, it appears so much more imperceptibly upon the inner surface, producing severe secondary ailments.
6. At the time before leprosy was reduced, there were much less nervous affections, painful ailments, spasms, cancerous ulcers, adventitious formations, weaknesses, paralysis, consumptions and degenerations of either mind or body, than there are now, aided probably by universal use of coffee and tea for the last two centuries.
7. The most universal of external means has done an immense amount of mischief, for secondary ailments will sooner or later manifest themselves as results of the psoric reaction.
8. Many cases from ancient and recent writers can be cited to convince the observer that the itch with its varieties, tinea capitis, crusta lactea, herpes, etc., are the external vicarious symptoms of an internal disease affecting the whole organism, and that psora is the most pernicious of all chronic poisons. It is well known that all infections first attack the whole organism internally before the vicarious affection manifests itself.
9. In acute diseases, the local symptoms, together with the disease, leave the system as soon as they have run through their regular course. In chronic diseases the local affection may either be removed or disappear by itself, when at the same time the internal disease may increase, unless it is cured by art.
10. In considering the formation of the three chronic maladies, psora, sycosis, syphilis, as well as that of the acute infectious diseases, three cardinal points must be noticed: 1, the period when the infection took place; 2, the period when the whole organism began to be tainted with the infectious poison, until it became a complete internal disease; 3, the manifestation of the external symptoms, by which nature indicates the complete development of the infectious disease in the internal organism.
11. The infection in acute as well as in chronic-diseases, takes place in a moment, provided this moment is favorable to the contagious influence; the whole nervous system becomes infected in a moment. The human small-pox, measles, etc., will run through their course, and the fever which is peculiar to each of these different forms of infection, together with the cutaneous eruption, will break out a few days after the internal disease has completed its development.
12. The mode of contagion in chronic contagious diseases is the same, but after the internal disease is completed, there is this difference, that the chronic poison continues in the organism, and even develops itself from year to year, unless it is extinguished and thoroughly cured by art.
13. Syphilitic contagion happens at those places which come in contact with the syphilitic virus and receive it into themselves by friction; the internal organism is roused in a moment by this infection, and not until the internal disease is completely developed, does nature try to form at the spot where the contagion took place, a local symptom as a substitute for the internal disease. By extinguishing the internal disease with an internal remedy, the chancre becomes also cured without any external application.
14. Psora is the most contagious of all chronic diseases, as it taints the system, especially that of children, by simply touching the skin. Not till the whole organism has been adapted to the nature of the chronic contagious disease, do the morbidly affected vital powers try to alleviate the internal disease by local symptoms and the eruption is merely the ultimate boundary of the psoric development, a substitute for the internal disease, which, together with its secondary ailments, remains in a latent condition. External applications may check the local symptoms, but too often the internal psora is thus aggravated.
15. There are many symptoms that reveal the existence of psora, but they cannot all be found upon one person; one has more, the other less, in one they come out progressively, in another they remain suppressed; this depends greatly upon the constitution and the external circumstances of the patient. These affections do not prevent him from leading a tolerably comfortable existence, provided he is young and robust, is not obliged to fatigue himself, has all his wants provided for, is not exposed to chagrin or grief and has a cheerful, calm, patient and contented temper. In this case psora may continue slumbering for years without becoming developed into a permanent chronic disease.