In this way, you can see the relics, and the Taoist inner alchemy can only be seen by people with perspective function, and only those who enter the realm of fetal interest can experience it personally. The so-called "Inner Dan", "Zedan", "Holy Fetus" and "Fetal Breath" are all the same metaphors, but they are not.
It shows that there is really a hard "elixir" in Xiadantian or other parts, or the fetus is really pregnant. The author understands the text of "Fetal Breath Sutra" and thinks that "Fetal Breath" is a function, that is, the respiratory function of the fetus. After the fetus is delivered, the umbilical cord is cut and the mouth and nose start breathing, and the role of "fetal interest" in the mother gradually disappears. After long-term practice, people who practice Neidan have recovered their "fetal interest" function in the fetal period. Therefore, practitioners who enter fetal interest have two functions: mouth and nose breathing and fetal interest. When you are concerned, your nose and mouth are still breathing, and the "fetal interest" in Xiadantian is constantly moving even when you are not practicing. Wang Wenlu's "The inscription of fetal interest": "Only vomit carefully, only collect continuously, sit and lie down, stand and run", that's what it means. At the same time of practicing martial arts, the mouth and nose breathing becomes small and thin, "as if there is nothing" and "if there is something, you will die." In meditation, "every breath stops, and real interest is automatic." At this time, the activity of the true qi in the body of the practitioner is exactly the same as the accumulation and dispersion of the fetal qi centered on the abdomen and navel: gathering is a group, and dispersing is invisible; The intensity is sometimes strong and sometimes weak, and the amplitude can be large or small. Great efforts, extending to Zhongdiantian and Shangdiantian. The weakness is small, so small that it only moves in the abdomen and even doesn't feel it. As Yang Zhenji said: "God congeals his breath and takes a breath. His abdomen turns and he can't get in or out, so he is called a breath." Therefore, fetal interest, that is, the essence of Inner Dan, is a combination of human vitality with vitality as the main body. At first, it gathered and dispersed in the human body, then it became a ball, and then it disappeared. As Mr. Zhang Youguang, a consultant of Inner Mongolia Qigong Science Research Association who has been engaged in the study of fetal interest for more than ten years, said in the article "My understanding and experience of fetal interest": "Usually, I always feel that the so-called fetal interest is actually a group of qi with strong cohesion and diffusion, which is constantly doing strong exercise with Dantian as the center, and at the same time forming a network of linkage and even continuous movement with viscera and meridians."
The reason why Taoism attaches great importance to the cultivation of Neidan in order to become immortal, that is, to enter the realm of fetal interest, is because the relationship between fetal interest and life expectancy is very close. The ancients said: "Take Dan and keep one, finish with the sky, be pregnant and prolong life." Because practitioners not only have the nose and mouth breathing of ordinary people, but also have the function of fetal interest that ordinary people don't have, the breathing function of pores in the whole body is stronger than that of ordinary people. Therefore, it can absorb a lot of cosmic energy to enhance physical fitness, and occasionally get sick and can be swept away in time. The body is full of vigor, vitality, vigor, vigor and vitality. Coupled with the usual emphasis on health care in daily life and diet, it is bound to get rid of illness and strengthen the body, prolong life, and even rejuvenate.