The Art of Medicine

C are adopted for the purpose of definition. Definitions are also made from the effect or office, and from the parts. Definitions from substantial differences are made in this way: "Man is a rational animal." Definitions from causes, such as the efficient cause: "The crudity of food is a poor digestion, born from the weakness of the altering faculty." Definitions from affections: "Disease is an affection contrary to nature, primarily damaging action." Definitions from parts: "A muscle is a part of the body consisting of nerves and flesh." Definitions from the end: "A house is a dwelling by which we protect ourselves and our belongings from external injuries." However, since all arts and sciences are placed in the genus of quality, they do not derive their differences from the genus of substance, but for the most part from their office, end, and parts: for example, the office of medicine is to repair what is missing in the body, and to remove what is superfluous. Therefore, Hippocrates Ancient Greek physician defines medicine as addition and subtraction. The end of the same science is health: therefore, with the difference taken from this, "Medicine is the art that is dedicated to the preservation of health." The parts of this science are also the healthy, the morbid, and the neutral. Therefore, Galenus Galen teaches that medicine, with the difference taken from these, is the science of healthy, morbid, and neutral things. Definitions of this kind are excellent because they contain the chapters of all medicine. For addition and subtraction contain the things which are