《參同契闡幽》

The Dao in its original state cannot be described with words nor confined to any form—it exists in primordial chaos without shape, its origins impossible to trace. Yet if we abandon language and concepts entirely, the true essence of the Dao would remain forever obscured. In ancient times, Fu Xi (the Flame Emperor) composed the Book of Changes (Yijing), revealing the heavenly Dao directly through the symbols of Qian (Heaven) and Kun (Earth). Laozi later wrote the Daode Jing, offering a complete exposition of the Dao's nature. It was through the wisdom of these two sages that the veil of chaos was lifted, allowing humanity to understand the source of their existence, and thus the profound truth of the Great Dao was illuminated.

The Book of Changes and the Daode Jing share the same origin, yet regrettably, later generations divided them into Confucian and Daoist traditions. Confucian scholars studying the Book of Changes became engrossed in divination and numerology, while Daoist practitioners following Laozi and Zhuangzi focused solely on longevity techniques. The true study of life's origin and the return to the Great Dao was nearly lost. It was not until the Eastern Han Dynasty, when Patriarch Wei Boyang (revered in Daoism as "Ancestor Wei") composed the Zhouyi Cantong Qi (The Kinship of the Three), that the essence of these two classics was synthesized.

This scripture employs hexagram symbolism to clarify the nature of "Xing" (innate nature) and "Ming" (life force): "Xing" refers to the eternal, indestructible primordial spirit (Yuanshen, the innate divine nature), while "Ming" is the ancestral Qi (Zuqi, the primordial vital energy) born from emptiness. These two are fundamentally one, manifesting as dual aspects. When speaking of the primordial spirit, it inherently includes essence (Jing) and Qi; when discussing essence and Qi, the primordial spirit is naturally present. To speak of "Xing" inevitably involves "Ming," yet Ming is not a concrete existence; to discuss "Ming" necessarily includes "Xing," yet Xing is not mere emptiness. The profound truth contained in these two characters can be explained separately yet unified as one, just as the Book of Changes takes Qian and Kun as the root of all hexagrams, and the Daode Jing governs all things through Dao and De. No matter how later schools expanded upon these ideas, none could escape this fundamental principle.

Following the natural order of development aligns with the Confucian maxim, "What Heaven imparts is called Xing" (Tianming zhi wei xing). Conversely, reversing this process through cultivation to return to the origin embodies the Daoist path of "exhausting principle and fulfilling nature to attain life's destiny" (qiongli jinxing yizhi yu ming). The true Great Dao ultimately converges to the same destination across Confucianism, Buddhism, and Daoism. Out of compassion, Patriarch Wei could have directly revealed the essence, but fearing that ordinary people would struggle to grasp it, he reluctantly constructed a conceptual framework from the ineffable, dividing the truth of Xing and Ming into seven volumes. These are further categorized into three major disciplines: governance (the Dao of ruling a state), self-cultivation (methods of refining the body), and internal alchemy (Neidan), with finer subdivisions into medicinal ingredients (alchemical materials), the furnace and cauldron (vessels of practice), and fire times (critical moments in cultivation).

This passage discusses the importance of the Taoist classic Cantongqi (The Seal of the Unity of the Three) and the spiritual journey of its commentator, Master Yuanyu. Regarded as the foundational text of Neidan (internal alchemy) literature, Cantongqi elucidates the principle of dual cultivation of nature and life (xingming shuangxiu) through three dimensions: "investigation" (can), "unification" (tong), and "harmonization" (qi). Its content spans seven scrolls, alternating between analytical discourse and synthetic exposition in such intricate patterns that its meaning remains inaccessible to casual readers.

From childhood, Master Yuanyu yearned for the Dao. He initially studied under Zhang Bixu of the Northern School, using Cantongqi as his primer, yet failed to grasp its profundity. His subsequent pilgrimages to the Five Sacred Mountains and consultations with countless masters left his spiritual doubts unresolved—until his fateful encounter in the depths of Zhongnan Mountain. There, the ancient sage Lingbao revealed to him the truth that "a millet grain contains universes, and Dharma wheels turn within specks of dust." Before parting, the sage charged him to disseminate these teachings widely, hinting that Jiangnan would prove fertile ground.

Settling later in Changzhou with fellow practitioners' support, Yuanyu devoted himself to cultivation. During the Dingyou year (exact date uncertain), while retreating with his disciple Pan Jingguan in Huayang Mountain, a sudden illumination struck him upon rereading Cantongqi—like a pauper discovering hidden treasure. Lamenting how centuries of commentaries had distorted the text, even by heterodox interpretations, he resolved to produce an authoritative exegesis. Through eighty days of secluded study, master and disciple would huddle by their furnace nightly, unpacking one or two chapters. When intellectual barriers arose, numinous insights occasionally descended. Their collaborative effort birthed this commentary.

(Note: "Mysterious Pass" [xuanguan] denotes critical alchemical junctures; "nature and life" [xingming] refers to primordial consciousness and vital foundation; Neidan constitutes Taoist immortality practices through refining Jing (essence), Qi (vital energy), and Shen [spirit].)

This work is titled Chan You ("Illuminating the Profound"), signifying that this scripture had long been concealed in the deepest recesses before finally resurfacing into the light. Like a treasure submerged for ages in shadowed valleys, it now basks in the radiance of the immortal pools (Xianchi, referring to the celestial ponds of Daoist lore). After completing the manuscript, I repeatedly revised it with Master Pan, stripping away all superficial ornamentation to preserve only the most essential truths.

Initially, I regarded it as my personal secret treasure (Zhenzhong Hongbao, denoting rare and precious texts). It was not until the Dingwei year [1667] that Master Xu Jingdu proposed its public circulation to share it with fellow seekers of the Dao. With the strong support of Master Zhang Jingjian, we gathered craftsmen to carve the woodblocks for printing. Fellow practitioners enthusiastically responded, and eventually, the seven-volume edition was completed in stages. At their request, I composed this preface, briefly recording the essential principles I received from my teacher and humbly seeking guidance from all accomplished adepts.

I hope readers will not cling to the literal meaning of the words or become entangled in conceptual distinctions. Instead, they should directly apprehend the true principle within. At first, one may grasp the patterns of Heaven and Earth's transformations, but ultimately, one must transcend all realms of emptiness. At this stage, there is no need to distinguish between methods of governing body and mind, cultivating the heart-nature, or ingesting elixirs. Nor is it necessary to separate the distinctions of medicinal ingredients (yao), the crucible (ding), and firing times (huohou, technical terms in Neidan practice). Even the two characters "nature and life" (xingming) can be relinquished.

Only by realizing this can one barely repay the kindness of Patriarch Wei Boyang (author of the Cantongqi), Patriarch Xu, and all the ancestral masters through the ages, as well as the profound grace of the ancient sages Fuxi and Laozi. The gratitude of all sentient and insentient beings—mountains and rivers, the vast earth, and all creatures that fly, swim, move, and grow—will also be repaid. The Dao is impartial and undifferentiated, manifesting its true principle everywhere. At that time, all beings, sentient and insentient, will radiate the great light of wisdom, dispelling darkness and illuminating the hidden depths. And I, too, shall remain silent in this state, having no need to say more.

Respectfully written by Zhu Yuanyu, a disciple of the Longmen lineage of the Northern School, on the first day of the second month in the Jiyou year of the Kangxi reign [1669].