When the Yellow Emperor asked Qi Bo about his practice, Qi Bo asked Su NV to teach the Yellow Emperor the art of combining Yin and Yang. This is the "Su NV Jing", from which the yin-yang school originated.

The practitioners of the Yin Yang sect have a sect doctrine and a determined concept of practice, which is that the decline of mortals is hurt by the way of the intersection of yin and Yang.

This means that ordinary people are getting weaker and weaker because of improper behavior in the intersection of yin and Yang.

Therefore, the Yin Yang school takes this as its fundamental doctrine and reversely puts forward that the reason why saints become stronger and stronger is beneficial to the Dao of the intersection of yin and Yang.

Although only a few words have been changed, the meanings are quite different. The practitioners of the yin-yang school believe that since ordinary people do not know the art of tonic, they behave improperly during intercourse, resulting in kidney injury, physical injury and mental injury. Finally, the essence, Qi and spirit are deficient, quantitative change forms qualitative change, and the strong gradually become the weak; Then the sage who knows how to practice can do the right way to combine Yin and Yang, so that he can complete the spiritual cultivation and strengthen himself.

So what is the right way?

Zhang Ding, a Taoist of the Yin Yang sect in the Tang Dynasty, once wrote a Book of practice called Dong xuanzi, which has been handed down for thousands of years. This book is another sect classic of the Yin Yang sect after the vegetarian Sutra, and has been regarded as the supreme treasure book by the Yin Yang sect so far.

This book holds that man is born with all things, and only man is the most expensive. There is no better place for people than house desire. Law heaven and earth, regulate Yin from Yang. Those who understand its reason will nourish their nature and prolong their age; Those who slow down the truth will hurt their nerves and die young.

That is to say, sex should follow the law of heaven and earth and the principle of yin and Yang, so as to prolong life, consolidate the foundation and strengthen the yuan.

This kind of cultivation method was originally the most reasonable in the world, the great Lun of people, and the yin-yang sect was once strong. However, due to the large trees and dead branches, in the Wei, Jin, southern and Northern Dynasties, the yin-yang sect once attracted heaven's anger and people's resentment because its disciples bewitched the foolish men and women in the countryside, committed adultery, defiled the four directions, and raped. * * women.

Subsequently, during the period of Taiwu emperor of the Northern Wei Dynasty, Kou Qianzhi, the northern Tianshi, launched the Taoist reform, publicly abolished the Fangzhong technique in the Taoist practice, and listed this practice method as the "forbidden method", "those who practice this technique will be cut down by the world", and then the yin-yang sect declined greatly.

Until the Tang Dynasty, when the people of the Tang Dynasty opened up and the yin-yang school rose again, Zhang Ding wrote a book to publicize the harmony of yin and Yang with the book Dong xuanzi. The yin-yang school was popular from the princes and Gongqing to the people.

But unfortunately... At this time, the fox Zen sect rose. After learning the art of yin and Yang, these fox spirits really increased their wings and became more and more demons. Many practitioners could not control the word "color", lost their essence and drain their yuan, fattened the cultivation achievements of a group of Fox spirits, and turned themselves into "drug residue" losers.

The behavior of fox Zen naturally angered the cultivation world. In particular, the emergence of Tianji xuanhu later made the yin-yang sect carry a lot of black pot. After driving away Tianji xuanhu, the practitioners in the cultivation world turned back to attack the yin-yang sect and destroyed many yin-yang sect experts.

After the Tang Dynasty, the yin-yang school never recovered until the song, yuan and Ming Dynasties. First, the orthodox school unified the Jianghu, and then the Quanzhen school rose. There was no place for the yin-yang school in the world's practice circle.