What is the original principle of eighteen evils and nineteen fears in traditional Chinese medicine?

This is mainly a long-term experience summary of the ancients. The principle is simple. When the medicinal properties are matched together. There is a mutual relationship. Shi Xiang hates each other. Fear each other. Kill each other. The opposite effect. Not just opposition and fear. In the collocation of traditional Chinese medicine, if you look at the prescriptions in the prescription, you will have a lot of knowledge in this field. Such as ephedra sweating in Mahuang decoction. Guizhi Jiebiao recipe These two drugs form a correlation. Eighteen opposites and nineteen fears are a special combination. The ancients thought. Eighteen anti-combination will make its toxic drugs more toxic. Not fit for disease. And nine is the same. Its collocation will weaken the medicinal properties. Just like two people who are naturally incompatible. Call as soon as we meet. You forced them to be together.