Samuel Hahnemann was the founding father of homeopathy and ORGANON OF MEDICINE was his magnum opus. His formulation of the fundamental law of healing, called the law of similars, states that a patient will be cured by a medicinal substance producing the same disease symptoms in a healthy person. First published in 1810, and revised many times by the author, ORGANON OF MEDICINE has remained the one essential cornerstone of homeopathy, the ultimate authority on its doctrine and practice.