The basic contents of the doctrine of yin and yang include yin and yang opposites, yin and yang mutual roots, yin and yang extinction and yin and yang transformation.
(i) Opposition of Yin and Yang
Yin and yang are in opposition to each other, meaning that there is a relationship of mutual exclusion, mutual struggle and mutual constraint between yin and yang. Opposition, that is, the opposite, such as movement and static, cold and heat, up and down, etc. are two opposing aspects of each other. The two opposing sides, through exclusion, struggle to mutual constraints, so that things reach a dynamic balance. Take the physiological functions of the animal body as an example, the function of hyperactivity for the Yang, inhibition for the Yin, the two mutual constraints, so as to maintain the physiological state of the animal body. Take the four seasons of heat and cold as an example, although summer is hot, but after the summer solstice, the yin is born to constrain the heat of the yang; winter, although the yin is cold, but after the winter solstice, the yang is born to constrain the cold of the yin. Because of the constant rejection and struggle between yin and yang, it promotes the change or development of things. Therefore, “Suwen - malaria theory” said “yin and yang up and down the fight, the virtual reality more work, yin and yang phase shift.”
(ii) Mutual Roots of Yin and Yang
Mutual root of yin and yang means that yin and yang are interdependent and fundamental to each other. That is, the yin or yang of any party, can not be separated from the other party and the existence of a separate, each party to the existence of the other side of the opposition as the premise and conditions of their existence. Such as heat for yang, cold for yin, there is no heat will not matter cold; on the yang, down for the yin, there is no on the bottom, there is an interdependence, interdependence of the relationship between the two sides, i.e., yang depends on the yin, yin depends on the yang.
Yin and yang mutual root and the meaning of mutual use, that is, yin and yang there is a mutual capitalization, mutual promotion of the relationship between the two sides. The so-called “lone yin is not born, the only yang does not grow”, “yin is born in yang, yang is born in yin,” that is to say that the “lone yin” and “the only yang” are not only interdependent, but also the “yin” and “yang”. This means that “solitary yin” and “sole yang” are not only interdependent, but also mutually productive and mutually reinforcing. Yin essence is produced through the activity of yang qi, and yang qi is generated from yin essence. At the same time, yin and yang also exist a “yin for the body, yang for the use of” interdependent relationship, “body” that is, ontology (structure or material basis), “use” refers to utility (function or function), the body is the material of the use of the body (function or activity), the body is the material of the use of the body. “Body” is the body (structure or material basis), ‘use’ refers to function (function or functional activity), the body is the material basis of use, and use is the functional performance of the body, the two are inseparable. For example, in Su Wen - Yin and Yang Ying Xiang Da Lun (素问-阴阳應象大论), it is said, “Yin is within, the guardian of yang; yang is outside, the enabler of yin.” Pointed out that the Yin essence within, is the Yang Qi's guard (root); Yang Qi outside, is the performance of Yin essence (servitude).
(iii) Yin and Yang Dissipation
Yin and Yang are in constant motion and change to maintain a dynamic and balanced relationship. Yin and yang in the case of opposition, mutual root, not static, but in the process of change, the so-called “yin and yang, yang and yin”. In the continuous process of elimination and growth, to maintain a relative dynamic balance. For example, the body's various functional activities (Yang) of the production, necessarily consume a certain amount of nutrients (yin), which is “yin消阳长 ‘process; and a variety of nutrients (yin) of the generation, but also must consume a certain amount of energy (yang), which is ’yang消阴长 ”process. This is the process of “yang consuming and yin growing”. This yin and yang growth and elimination is kept within a certain range, and the yin and yang sides maintain a relative state of equilibrium. If this waxing and waning of yin and yang exceeds the normal range, resulting in a dislocation of the relative equilibrium relationship, disease will be triggered. Such as “Su Wen - yin and yang should be like the great theory” in the “yinheng is yang disease, yangheng is yin disease,” is due to changes in yin and yang, making the balance of yin and yang is out of balance, resulting in “yang qi deficiency” or “yin fluid insufficiency “Its treatment should be based on the principle of warming and tonifying yang qi and nourishing yin to increase fluid, so that yin and yang can be rebalanced.
(iv) Yin-yang transformation
Yin and yang transformation refers to the relationship between yin and yang under certain conditions, mutual transformation and interchangeability of attributes. That is, under certain conditions, yin can be transformed into yang, yang can be transformed into yin. As stated in “Su Wen - Yin and Yang Ying Xiang Da Lun”, “Heavy yin must be yang, heavy yang must be yin” and “Cold extremity gives birth to heat, and heat extremity gives birth to cold”. If yin and yang are quantitative changes, yin and yang transformations are qualitative changes. In the process of disease development, yin and yang transformation is often seen. Such as animals with wind-cold, cold ears and nose, muscle tremors and other cold phenomena; if the treatment is not timely or treatment errors, the cold into the heat, there will be a dry mouth, tongue red, gas thick and other hot phenomena, which is the transformation of yin to yang evidence. Another example is that animals suffering from febrile illnesses, due to the persistent high fever, the heat is very injurious to the fluid, qi and blood are deficient, showing weakness, cold limbs and other symptoms of cold, which is the transformation from yang to yin evidence. In addition, the clinical changes of solid to deficiency, deficiency to solid, from the surface to the inside, from the inside to the surface, etc., are all examples of the transformation of yin and yang.
The opposition, mutual root, growth and transformation of yin and yang are the basic contents of the yin and yang doctrine. Understanding these contents is conducive to the understanding of the application of the yin and yang doctrine in Chinese veterinary medicine.
