Proving, or experimentation with remedies on healthy individuals, is a third principle and a must for any medicinal science. Hahnemann gave detailed instructions for provings in his Aphorisms 105-114. He was the first to introduce the concept of scientific experiments on medicinal substances as a basis for prescribing with them. From ancient times until well into the 18th century, much of what was known about drugs was based upon pure speculation or symptoms caused by poisonings.
For the first time in the history of medicine, a doctor conceived the idea of testing medicines on himself so that he could observe their properties in detail. Hahnemann proved more than a hundred remedies on himself. And later, under his supervision, his pupils (mostly physicians and family members) experimented with a vast number of substances, noting all their effects. Before Hahnemann’s innovation, drug effects were only known from reports of accidental poisonings. These only reveal the most extreme symptoms, which are primarily physical rather than mental/emotional.
In Homeopathy, however, a vast amount of information is available form the provings about each of the major remedies and its effects, not only on all the tissues, organs and functions of the body, but even on the mind, the emotions and the energy level. Since the same remedies have been used for two centuries, information about the therapeutic effects of the remedies has been confirmed from clinical experience.
Hahnemann started his provings in 1789 with crude medicines in doses that were very small relative to the doses commonly used in medicine then. But even these comparatively small doses, when applied in accordance to the law of similars, caused such a violent aggravation of sufferings that Hahnemann was forced to experiment with ever-smaller doses. At first he simply divided the remedies into ever-smaller crude doses (i.e. still containing measurable amounts of the medicinal substance).
Provings must include mental and emotional as well as physical changes. No new symptom should be omitted no matter how trivial. It may be of little significance to the medical diagnosis but of the greatest value in choosing the right remedy. What can be apparently more trivial than the sensation “of a hair felt in the throat”? Yet this proving symptom later became the deciding factor in selecting Arsenicum by one of our great masters in one of his greatest restorations to health.