《玄牝之门赋》

"The Gate of the Mysterious Female" (xuanpin zhi men) is the pivot between the "Mysterious" (xuan) above and the "Female" (pin) below. Xuanpin is a technical term in alchemy for the crux where Yin-Yang meet and primordial Qi (qi) enters and leaves. Within a single aperture lies the root of the Great Elixir's cultivation. It is like a valley in empty space, a gateway through which the breath comes and goes. The furnace and cauldron are distinguished as upper and lower, facing one another, and the opening, closing and transformation of the mechanism within them are too subtle to describe. The immortals took this as the foundation of their practice. Primordial Qi moves ceaselessly up and down, and symbols of alchemy such as the lead furnace and mercury cauldron are established on this basis. "Jade Tower" and "Golden Pass" are both veiled terms of the practice, and very few truly grasp their meaning. The Mysterious Female is vast and profound and cannot be exhausted by any name. Because it joins Yin and Yang, it is called a "gate."

Within this gate, the furnace and cauldron conceal mercury and lead. To the east it connects to the Valley of Fusang, and to the west it reaches the summit of Mount Hua. It holds the vital point of the "Two Earths" and brings them together, and it stands between the "Two Chords" and divides them evenly. "Two Earths" and "Two Chords" are both symbolic terms of Neidan (neidan, internal alchemy), referring to the coordination of forces such as Yin-Yang and the Five Phases (wuxing). It is so great that it has no boundary, and so small that it has no interior. Its lower part is called the "Female" and its upper part the "Mysterious." The cinnabar cauldron and the crescent-moon furnace operate within the same mechanism, which is also called the "Pass of Returning to Life" or the "Aperture of Returning to the Root," meaning the point of passage back to the root of life. All subtle transformations gather here, and so it is the Gate of the Mysterious Female.

When Yang Qi opens and Yin Qi closes, the changes of opening and closing never end, and the sun and moon go back and forth without rest. The upper part is called the "Heavenly Pass," which takes in "Qian-Jia" at its center, and the lower part is called the "Earthly Door," which holds "Kun-Gui" within. "Qian-Jia" and "Kun-Gui" are terms that pair the Heavenly Stems with Yin and Yang. This gate has no edge and is not a physical thing, yet when it opens and closes once, its function as a gate appears. Upper and lower correspond with one another, vast and subtle, and the circulation of the breath, coming and going, all passes in and out through it.

What, then, is this aperture? Everyone has it by nature, yet although it is not a gate in any physical sense, it is called a gate, and few people in the world know of it. Heaven and earth are always in the midst of coming and going and joining, and Shen (shen, spirit) and Qi likewise blend into one in their unbroken movement. The practitioner must open this aperture within the primal chaos and establish the foundation of the "True One" (zhenyi). The "True One" refers to the original state in which the myriad things have not yet divided and primordial Qi is still undifferentiated. In terms of the double-hours, the lower Female corresponds to the Zi hour, and in terms of the Bagua (bagua, Eight Trigrams), the upper Mysterious corresponds to the Li trigram. This division is made only to explain position and relationship, and the actual aperture remains a single undivided whole. This is why Zhang Ziyang explained these little-known principles in such detail. Otherwise, why would Laozi have said that the myriad things "emerge from the same source"?

The deep Female Gate seems hidden beneath the vast sea, and the lofty Mysterious Pass seems to lie atop Mount Kunlun. Yin and Yang are distinct, yet they are without color or form and hard to depict. The Four Cardinal Positions are arranged here, linking Zi, Wu, Mao and You, and the sun and moon also move here, matching the lunar phases of the last day, the quarters, the new moon and the full moon. The "Four Cardinal Positions" are the four directions, and the "Two Luminaries" are the sun and moon. Although the two characters xuan and pin are subtle, they are the key to gathering and refining in practice. Below lies the White Tiger, the pivot that sets the firing process in motion. Above stands the Azure Dragon, which stirs the movement of Qi and lifts it like rising clouds and a rushing wind. The White Tiger and the Azure Dragon are both symbols in Neidan for Yin-Yang and the movements of Qi.

The author criticizes minor side paths that mislead people, and also those who style themselves specialist masters. If they do not understand these principles, how can they accord with the immortals' books? To call the heart and kidneys the Mysterious Female only wastes effort on visualization, and to take the mouth and nose for the Mysterious Female is merely to practice breathing in vain. If one can abandon mistaken teachings, return to the right path and find the true way of cultivation, one can proceed from the shallow to the deep and enter gradually into the subtle. This does not mean stopping at the outer gateway.

One should also reflect on the following. The single Qi, spiritual and wondrous, has what as the root of its storage? The Qi of primordial harmony circulates in the body, and what governs the meeting of Yin and Yang? The tiger should be white and the dragon azure, so why do some speak of a black tiger and a red dragon? The Mysterious is above and the Female below, so why do some speak of the Mysterious on the left and the Female on the right? One should understand that Wood and Fire kindle one another, with Wood hidden within Fire, and that Metal and Water dwell in the same palace, with Metal lying concealed within Water. This is what is meant by "mystery upon mystery, wonder upon wonder." The principles of creation and transformation within it can be discussed without end.

A speck of true golden medicine, like a single grain of gold millet, has its source of growth in the water. Refined through the "Nine Returns" (jiuhuan), it becomes the Great Medicine, and within moments its miraculous efficacy appears. When the harmonious Yang qi in the Primal Sea (Yuanhai, a Neidan term for the place in the body where primal Qi gathers) is stirred, the Qi channels, like a cold spring, flow freely. In an instant it transforms into a white liquid, which congeals and fills the Yellow Palace (Huanggong, a Neidan term for a site of cultivation within the body). When it lies hidden, it is nourished by the Qi of Kun Earth; when it is stirred into motion, it is fanned by the Qi of Xun Wind. When will I be able to carry this treasure in my arms and go to visit the Immortal Master Lü (Lü Dongbin, a legendary immortal)?

The passage above comes from the Yiwai Biezhuan (Separate Transmission Beyond the Changes). For this book, the author drew diagrams and wrote explanations, expounding the most profound principles of the Xiantian Tu (Diagram of Prior Heaven). He corroborated them with works such as the Cantong Qi and the Yinfu Jing, and also drew on the subtle discussions of Confucian scholars such as Yichuan and Hengqu, developing points Master Zhu Xi had not yet clarified and extending the unspoken meaning of Master Shao.

Although I have had no time to devote myself to studying these matters, I do not know the wonders of Neidan (internal alchemy) merely in theory; I have also tried them out myself. For this reason I venture to point directly to the essentials transmitted by the alchemists and to dispel the doubts of scholars. I have often lamented that the alchemical classics circulating in the world mostly use obscure language, leaving readers without any thread by which to enter; dazzled and confused, they can only close the book with a sigh. Cai Jitong and Yuan Jizhong once collated the Cantong Qi together with Zhu Xi, and although they were able to investigate the meanings of its characters, they never received a genuine transmission, and so could not avoid interpreting by guesswork in the end.

Now that I have received the transmission, how could I bear to hide it and keep it only for myself? So I have appended this book to my Zhouyi Jishuo (Collected Explanations of the Zhou Changes) and titled it Yiwai Biezhuan. This is because, although the alchemists' teachings borrow the language of the Yi, they merely rely on and imitate the Yi, and are not its original meaning. The broad outline and essential points of the Dao of alchemy I have explained in detail in this book, while the subtle oral instructions are fully recorded in the three chapters of the Cantong Qi Fahui, and so I will not repeat them here. Inscribed by Yu Yan, styled Yuwu, the Recluse of the Stone Stream, of the Linwu Grotto-Heaven.

This volume, the Yiwai Biezhuan (Supplementary Commentary Outside the Changes), was originally written by my late father and appended to his Zhouyi Jishuo (Collected Explanations of the Book of Changes). My father once met a recluse who used the Xiantian Diagram (Diagram of Prior Heaven) to point out to him Master Shao's "center of the ring," a state of extraordinary subtlety. For this reason, the book elaborates Master Shao's teachings in many places.

Recently, the Yinfu Jing Jie (Explanation of the Scripture of the Hidden Talisman) was printed. My son Zhen asked that this text be copied out and handed over to the engraver together with it for printing. With the addition of the Qinyuan Chun Jie (Explanation of the "Spring in the Garden of Qin" Lyric), the three works were combined and compiled into a single volume, so that the lofty scholars of the world might study them together. Accordingly, I asked that these works be given the collective title Xuanxue Zhengzong (The Orthodox Lineage of Mysterious Learning).

In the spring, the first month of the Bingshen year of the Zhizheng era, written respectfully by my son Zhongwen.