According to the outline of Yin and Yang, eight benefits refer to eight symptoms of Yang Sheng, such as body heat, stagnation, wheezing, pitching, sweating with heat, dry teeth, upset, and abdominal death, while seven damages refer to seven symptoms of yin, such as body cold, sweating, refreshing body, counting chestnuts, cold, syncope, and abdominal death.
Yin and Yang Shu number theory: According to the theory of Yin and Yang Shu number in Zhouyi, Zhang Jingyue, a famous doctor in Ming Dynasty, called "seven" as "the number of less yang" and "eight" as "the number of less yin", and expounded it in combination with his academic proposition of supporting yang and restraining yin.
Four images theory: based on ancient divination, according to the four images represented by seven, eight, six and nine, this paper expounds a common sense of traditional Chinese medicine, that is, the wood of the East can be damaged but can not be replenished, and the water of the West can not be replenished.
Sexual intercourse theory: take "the theory of Tao in the world" as the core, and count seven to eight. Point out several advantages and disadvantages that should be paid attention to during sexual intercourse.
The theory of alchemy is based on the Book of Changes and the Book of Luo, which originated from the situation that the Book of Changes and the Book of Luo correspond to the human body's meridians and viscera. It expounds a core cultivation concept in alchemy-raising the kidney and lowering the heart, so as to explain the seven damages and eight benefits.
The law of growth says: Wu Kun, a famous medical scientist in Ming Dynasty, pointed out: "Those who suffer from seven losses, the women's day is marked by seven, the day is marked by twenty-seven, the month is now, and the yin and blood are often deficient, so it is called seven losses;" Those who have eight benefits, men take eight as the discipline, and they are full of days on the 28 th. Yang is always surplus, and there is no loss in the month, so it is called eight benefits. "
The above are some famous theories about "seven losses and eight benefits", but there are still many related theories that have not been mentioned here.