In cases where the well-indicated remedy does not work, a remedy must be prescribed on the basis of knowledge of cause alone. For example, homeopaths give Tuberculinum or Carcinosin on the basis of tuberculosis or cancer in the family tree, Arnica for an old injury, or Nux vomica to clear the effect of drugs. All of this is in the traditional and current literature. This approach is neither logically consistent, nor fully effective. What is needed to give homeopathy the full power of Hahnemann's insights into chronic disease is to take causation as the central basis of prescribing in chronic cases, with auxiliary reference to the symptomatology.
Chronic disease is an etiologically-centred universe.
In such an approach, all suspected causes should be treated for in the reverse order of their occurrence, in accordance with Hering's third direction of cure, using remedies that have been clinically identified with a particular cause. It is not logical to treat only for the straw that breaks the proverbial camel's back, or for the one drop that causes the cup to run over. Dr. Compton-Burnett, a 19th century British homeopath who pioneered the use of nosodes, was once asked by a student which of the several remedies that he had used in a case had cured. He replied by asking the student to take a ladder and when he reached the roof to tell him which of the rungs had taken him there. The vital force, once stimulated, begins a process of chronological retracing.