Traditional Chinese medicine determines yin and yang by taking the pulse

　　Traditional Chinese medicine has a theory of distinguishing yin and yang in taking the pulse. "Suwen·Yin and Yang Yingxiang Dalun" states: "Looking at the face and feeling the pulse, first distinguish yin and yang. ”, also said that "yang diseases should be treated with yin, and yin diseases should be treated with yang". Zhang Zhongjing divided typhoid fever into yin syndrome and yang syndrome, with three yin and three yang as the general outline. Zhang Jingyue, a physician in the Ming Dynasty, also emphasized that "when diagnosing the pulse and applying treatment, one must first examine yin and yang, which is the outline of medical ethics." This yin and yang is the general outline of the eight cardinal principles of syndrome differentiation. It can govern the three pairs of principles of exterior and interior, cold and heat, and deficiency and excess. Therefore, some people call the eight cardinal principles "two principles and six essentials". It can be seen that yin and yang syndrome differentiation plays an important role in disease syndrome differentiation.

　　Traditional Chinese medicine determines yin and yang by taking the pulse

　　Yin syndrome and Yang syndrome

　　All diseases that are located in the body, blood, are cold, have insufficient righteousness, and show signs of decline in the body's response are all yin syndromes. Symptoms include listlessness, pale complexion, fear of cold and cold limbs, shortness of breath and low voice, lack of thirst, loose stools, clear urine, pale tongue with white coating, slow and weak pulse, etc. The etiology and pathogenesis include old age, frailty, long-term internal injuries, or external pathogens transmitted internally to the internal organs, resulting in weakened righteousness and deficiency of yang and excess of yin.

　　Any disease that is superficial, qi-based, is real, is hot, the righteousness is not damaged, and the body's reactions are mostly hyperactive, all fall within the scope of yang syndrome. Symptoms include irritable mood, hot face and body, loud voice, thirsty for cold drinks, heavy breathing, abdominal pain that refuses to be pressed, constipation, short and red urine, red and crimson tongue with yellow coating, floating and rapid pulse or slippery and weak pulse. Its etiology and pathogenesis are the invasion of evil qi, the strong evil and strong righteous qi, and the fierce competition between good and evil.

　　Yin deficiency and Yang deficiency

　　Yin deficiency and yang deficiency are syndromes caused by the deficiency of yin and yang in the human organs. Under normal physiological conditions, the human body's yin and yang must maintain a relative balance, that is, "yin balances yang secretly, and the spirit governs" ("Suwen·Qi Tongtian Lun"). Once yin and yang lose this relative balance, changes in the rise and fall of yin and yang will occur, resulting in diseases.