The Evolution of the “Three Dots of the Character Yi” in Mahāyāna Buddhism: With a Focus on Fang Yizhi’s “Perfect ∴” Theory

Abstract

Fang Yizhi was a prominent Confucian Buddhist philosopher of the late Ming Dynasty, whose thought centered on the theory of “Perfect ∴.” This paper traces the evolution of the meaning of the “three dots of the character Yi” in texts of the Tiantai, Huayan, and Chan schools of Chinese Mahāyāna Buddhism. Building on this foundation, and by integrating the specific texts and ideas of Fang Yizhi, this paper analyzes how his theory of the Perfect ∴ synthesizes the philosophy of the Zhouyi, reformulates the conceptual content of the Buddhist symbol ∴, and thereby offers a new potential pathway for understanding the intellectual trend of the synthesis of the Three Teachings in the late Ming Dynasty.

1. Introduction

The transitional period between the Ming and Qing Dynasties was marked by social turmoil and, at the same time, by the emergence of innovative ideas, during which a number of unconventional philosophers came to prominence. Fang Yizhi 方以智 (1611–1671) was one of the most notable figures among them. Fang was born into a family of Confucian scholar–officials. In his early and middle years, he built upon his father’s and grandfather’s accomplishments in the study of the Book of Changes (Zhouyi 周易) and became an expert in this field. After the fall of the Ming Dynasty, Fang Yizhi, at the age of 52, became a disciple of the Caodong 曹洞宗 Chan master Juelang Daosheng 覺浪道盛 (1592–1659), and he dedicated himself to the study of Buddhist doctrines until his passing at the age of 61.1 During his tenure as a Chan monk, Fang Yizhi fulfilled Daosheng’s commission by completing a commentary on the Zhuangzi 莊子. This exegetical work elucidates the Zhuangzi through Chan public case (gong’an 公案) while reinterpreting its philosophy through a Confucian lens. During the late Ming Dynasty, the synthesis of the Three Teachings—Confucianism, Daoism, and Buddhism—culminated at an unprecedented level in history. In particular, the profound integration between Confucianism and Buddhism, which formed the most influential strand of this trend, emerged as a central topic of scholarly discourse. Within this intellectual milieu, Fang Yizhi stood out due to his dual identity as both a Confucian scholar and a Chan Buddhist monk, as well as his profound mastery of the doctrines of all Three Teachings.

In recent years, the extant works of Fang Yizhi were edited and published in mainland China, triggering an increased interest in his philosophical thought, and followed by a great number of scholarly papers by Chinese academics. The majority of Chinese scholars agree that the “Perfect ∴” (圓∴ yuanyi, “∴” read as yi) embodies the essence of Fang Yizhi’s philosophy.2 Fang’s Perfect ∴ theory represents the most prominent conceptual framework developed around the symbol “∴” in Chinese history. This theory incorporates the traditions of Buddhism and the Zhouyi, establishing a comprehensive conceptual system. In the context of Buddhism, it is now established that the symbol ∴ derives from the Siddham script form of the Sanskrit letter “i.” This letter was initially written as or , later simplified into three dots distributed in a triangular pattern, “∴,” and was also transliterated as characters yi 伊/依/以 in Chinese scriptures.3 However, the precise and profound implications of the Buddhist “three dots of the character Yi” or the symbol ∴, which were integrated into Fang Yizhi’s Perfect ∴ theory, continue to elude clear understanding.

This paper begins by tracing the evolution of the meaning of the “three dots of the character Yi” in the classical texts of the Tiantai 天臺宗, Huayan 華嚴宗 and Chan 禪宗 schools of Chinese Buddhism. Building on this foundation, and by integrating specific texts and ideas of Fang Yizhi, it analyzes how his theory of the Perfect ∴ synthesizes the philosophy of the Zhouyi, reformulates the conceptual content of the Buddhist symbol ∴, and thereby offers a new potential pathway for understanding the intellectual trend of the synthesis of the Three Teachings in the late Ming Dynasty.

2. The “Three Virtues of Nirvāṇa” as Described in the Mahāparinirvāṇa Sūtra

Chinese scholars generally contend that the Buddhist origin of Fang Yizhi’s Perfect ∴ theory can be traced to the passage concerning the “Three Virtues of Nirvāṇa” (sande niepan 三德涅槃) in the Mahāparinirvāṇa Sūtra.4 In the 40th fascicle of the Daban niepan jing 大般涅槃經, translated by Dharmakṣema (also called the “Northern Edition”), the passage mainly appears in the Chapter on Life Span (Shouming pin 壽命品), whereas in the 36th fascicle of the Daban niepan jing, compiled mainly by Huiyan 慧嚴 (also known as the “Southern Edition”), this passage is arranged in the Chapter on Lamentation (Aitan pin 哀歎品). The two texts are largely identical. Below is a translation of the original text of the Northern Edition:

“Bhikṣus! Just as the earth, mountains, and medicinal herbs benefit sentient beings, so does my Dharma. It provides the wonderful nectar of the Dharma and serves as the excellent medicine for the afflictions and diseases of sentient beings. Today, I will enable all sentient beings and my fourfold assembly of disciples to dwell securely in the secret repository. I will also dwell therein and enter Nirvāṇa. What is called the secret repository? It resembles the three dots of the character Yi (伊字三點). If [the three dots] are horizontally arranged, they do not form Yi; nor does their vertical arrangement result in the formation of Yi. Similarly to the three eyes on the face of Mahêśvara5, it is capable of forming the Yi character. If the three points are separated, it cannot be accomplished either. I am also like this. The dharma of liberation is not Nirvāṇa, the body of the Tathāgata is not Nirvāṇa, the Great Wisdom (mahāprajñā) is also not Nirvāṇa, and the three dharmas, being distinct from one another, also do not equate to Nirvāṇa. I now abide in these three dharmas and for the sake of sentient beings, [I] call it ‘entering Nirvāṇa’, like the Yi character in the world.”

「諸比丘！譬如大地、諸山、藥草為眾生用，我法亦爾。出生妙善甘露法味，而為眾生種種煩惱病之良藥。我今當令一切眾生，及以我子四部之眾，悉皆安住祕密藏中，我亦復當安住是中，入於涅槃。何等名為祕密之藏？猶如伊字三點，若並則不成伊，縱亦不成；如摩醯首羅面上三目，乃得成伊。三點若別，亦不得成，我亦如是。解脫之法亦非涅槃，如來之身亦非涅槃，摩訶般若亦非涅槃，三法各異亦非涅槃。我今安住如是三法，為眾生故，名入涅槃，如世伊字。」6

This text documents the important teachings of the Buddha regarding the connotation of Nirvāṇa as conveyed to his disciples prior to his attainment of Nirvāṇa. In the Nirvāṇa masters’ interpretation of this text, this teaching was systematized as follows: Nirvāṇa constitutes the embodiment of liberation (jietuo 解脫), Dharma-body (fashen 法身), and wisdom (bore 般若), collectively termed the “Three Virtues of Nirvāṇa.”7 Liberation, the Dharma-body, and wisdom constitute a “trinity,” embodying a relationship that transcends both “horizontal and vertical” dimensions, as well as “conflated and distinct.” Given its complexity, this concept is often challenging for laypersons to comprehend and is thus referred to as the “secret repository” (mimi zang 秘密藏). The “three dots of the character Yi” in conjunction with “the three eyes on the face of Maheśvara” (which are also arranged in the shape of “∴”) serve as a precise metaphor for the unique relationship among the three virtues of Nirvāṇa.

Upon the translation of the Mahāparinirvāṇa sūtra, it garnered significant attention among Buddhists and served as a pivotal factor in the transition of Chinese Buddhism from Prajñāpāramitā studies to the study of the doctrines and concepts of the Nirvāṇa Sūtras during the Northern and Southern Dynasties (420–589).8 The records in the Collective Interpretation of the Mahāparinirvāṇa Sūtra 大般涅槃經集解 reveal that, during this period, Nirvāṇa masters frequently encapsulated the core concept of the Nirvāṇa Sūtra using the “Three Virtues of Nirvāṇa.” Consequently, the originally commonplace metaphor of the “three dots of the character Yi” within the scripture evolved into a symbol representing Nirvāṇa studies in China. However, the Nirvāṇa masters did not accord the same level of importance to the three virtues, leading to intense debates.

W. Zhang (2024, pp. 163–68), in his latest research on the Nirvāṇa studies in the Southern and Northern Dynasties, indicates that the interpreters of the Nirvāṇa Sūtra have experienced a significant shift in their understanding of the three virtues of Nirvāṇa, transitioning from an emphasis on “wisdom” to a focus on “Dharma-body.” Influenced by Kumārajīva’s (344–413) promotion of the Prajñāpāramitā studies, Daosheng 道生 (355–434) and Sengliang 僧亮 (fl. Liu Song Dynasty) posited that, among the three virtues, “wisdom” was the most exalted, symbolically represented as the upper dot of the three dots in the Yi-character. Both Dharma-body and liberation were considered subordinate to “wisdom” and thus corresponded to the lower two dots. As Sengliang elucidated: “The analogy of three eyes on a face signifies the wisdom occupying the superior position, while body and liberation, being of equal stature, are positioned below.”9 Although Dharma-body, wisdom, and liberation are all unconditioned and unceasing, the wisdom holds a higher value than the other two. Starting with Baoliang 寶亮 (444–509), an increasing number of annotators began to focus on the Dharma-body and positioned it as the highest point among the three key elements represented by the Yi-character.

As one of the three bodies of the Buddha (Dharma-body 法身, Response-body 應身 and Reward-body 報身), the Dharma-body embodies the qualities of permanence and immutability. Baoliang posits that this characteristic constitutes the fundamental distinction between Mahāyāna Nirvāṇa and Hīnayāna Nirvāṇa. Baoliang explained: “The term ‘horizontally’ (bing 竝/並) serves as a metaphor for simultaneous coexistence. Why? In the past, Nirvāṇa was defined through the cessation of conditioned activities to realize the unconditioned. However, since this unconditioned state coexists with the body and wisdom, it differs from the present triangular symbolism of the character Yi. The ‘vertically’ (zong 縱) denotes temporal succession, also illustrating the former concept of ‘Nirvāṇa without remainder’. It implies the initial existence of the body, followed by the emergence of wisdom, and finally the attainment of cessation—hence this interpretation is deemed incorrect.”10 Hīnayāna advocates “Nirvāṇa without remainder” (wuyu niepan 無餘涅槃), which posits that the Buddha’s physical body attained complete liberation, free from all defilements, upon passing into Nirvāṇa. The relationship among the three virtues, as they understand it, can be categorized as either “horizontal” or “vertical.” A “horizontal” relationship implies that the three virtues are distinct and independent from one another, while a “vertical” relationship suggests a sequential order, wherein the Dharma-body gives rise to wisdom, and the wisdom leads to liberation. Mahāyāna Buddhism rejects the notion of Nirvāṇa as “destroying the body and eliminating wisdom” (huishen miezhi 灰身滅智), asserting instead that the Buddha’s body is eternal. The teachings and spirit of the Buddha, embodied in the Dharma-body, transcend time and space. Given the eternality of the Dharma-body, it enables the functions of wisdom and liberation to arise, which together converge into the state of Nirvāṇa.

During the Northern and Southern Dynasties, Nirvāṇa masters elevated the interpretation of the “three dots of the character Yi” to a pivotal role in comprehending the Mahāyāna Nirvāṇa doctrine. Although they held differing views regarding how exactly liberation, the Dharma-body, and wisdom corresponded to the three dots, they universally integrated the substance–function (tiyong 體用) framework from Wei-Jin metaphysics (xuanxue 玄學). Within this framework, they identified the upper dot of the Yi-character as representing “substance,” and the lower two dots as representing “function,” implying that a single fundamental substance gave rise to two distinct functions. The upper dot in the “∴” symbol is regarded as pivotal for attaining Nirvāṇa, thus holding a more foundational status than the lower two dots.

3. The Perfect Interfusion of the “Triadic Dharmas” in Tiantai Buddhism

The Tiantai, Huayan, and Chan schools, which formed during the Sui and Tang dynasties, did not regard the Nirvāṇa Sūtra as their supreme scripture. Nevertheless, they absorbed, to varying degrees, the resources from this sūtra to construct and refine their own doctrinal systems. Zhiyi 智顗 (538–597), the de facto founder of the Tiantai school, extensively employed the relational model symbolized by the Yi-character in his representative works, such as the Three Great Treatises of the Tiantai School (Tiantai sanda bu 天臺三大部)11, integrating the school’s “triadic dharmas” into a doctrinal framework characterized by “perfect interfusion” (yuanrong 圓融).

In the Mohe zhiguan 摩訶止觀 (Great Cessation and Contemplation), Zhiyi elaborates on the Tiantai school’s doctrine of the “perfect and sudden cessation and contemplation” (yuandun zhiguan 圓頓止觀). Within this text, he raises a rhetorical question: Since “cessation” and “contemplation” constitute only “two” methods, how can they numerically align with the “three” virtues of Nirvāṇa? Zhiyi responds by presenting a threefold argument: First, each of the two methods—cessation and contemplation—encompasses all three virtues. Second, the two methods and the three virtues are fundamentally interconnected—“liberation corresponds to cessation, wisdom corresponds to contemplation, and the Dharma-body corresponds to neither cessation nor contemplation.” Finally, he cites various scriptures to demonstrate that the relational model symbolized by the Yi-character permeates “all triadic dharmas” (yiqie sanfa 一切三法) in the teachings of Mahāyāna Buddhism:

If one believes that the three virtues are neither vertical nor horizontal, neither conflated nor distinct—like the three dots or the three eyes—then one should also believe that the threefold cessation and threefold contemplation are likewise neither vertical nor horizontal, neither together nor separate. However, the scriptures, adapting to the capacities [of sentient beings], often one-sidedly emphasize one method to illustrate a particular doctrinal point. […] Just as cessation and contemplation encompass the three virtues in this manner, they similarly permeate all other [triadic] names—such as “staying away from conceptual knowledge”—and so on. Moreover, they extend to all triadic names, the so-called threefold enlightenment, the three Buddha-natures, the three treasures, and indeed all triadic dharmas in the same way.

若信三德不縱不橫、不並不別，如三點、三目者，亦信三止三觀不縱不橫，不並不別也。而諸經赴緣，偏舉一法，以示義端。……止觀通三德既爾，通諸異名，遠離知見等，亦如是。又通諸三名，所謂三菩提、三佛性、三寶等，一切三法，亦如是。12

Zhiyi’s concept of “all triadic dharmas” not only encompasses the aforementioned triads—such as the threefold enlightenment (san puti 三菩提), the three Buddha-natures (san foxing 三佛性), and the three treasures (san bao 三寶)—but also employs the Yi-character metaphor to interpret numerous other triadic categories. These include: the three kinds of liberation (san jietuo 三種解脫), the three realms (san dao 三道), the three consciousnesses (san shi 三識), the three wisdoms (san bore 三般若), the three Mahāyānas (san dasheng 三大乘), the three buddhas (san fo 三佛), the three kinds of Nirvāṇa (san niepan 三涅槃), and all other such triadic doctrinal formulations.13

Taking the Tiantai school’s distinctive doctrine of “the perfect interfusion of the threefold truth” (sandi yuanrong 三諦圓融) as an example, Zhiyi posits that the true existence of all phenomena encompasses three aspects—the truth of emptiness (kongdi 空諦), the truth of nominal/provisional existence (jiadi 假諦), and the truth of the Middle Way (zhongdi 中諦)—collectively termed the “threefold truth.” The “truth of emptiness” signifies that all phenomena arise from dependent origination and lack an inherent, unchanging nature. Since the conditions composing any phenomenon are in constant flux, phenomena themselves are transient, arising and ceasing instantaneously—their fundamental nature is intrinsically “empty.” The “truth of nominal existence” refers to the fact that, although phenomena are empty in nature, they nevertheless manifest as specific appearances, giving rise to the vast diversity of the world. The “truth of the Middle Way” is the realization that all phenomena simultaneously embody both “emptiness” and “nominal existence,” thereby enabling one to apprehend the true reality of all dharmas.

Zhiyi identified a misconception regarding the threefold truth, wherein the three truths were erroneously perceived as non-fused and as having either a sequential (vertical) or parallel (horizontal) relationship—temporally ordered in succession or spatially separated from one another. Some mistakenly believed that one should first contemplate the truth of emptiness, then the truth of nominal existence, and finally the truth of the Middle Way, thus assuming that the Middle Way could only be realized by transcending both emptiness and nominal existence. This mode of thinking fails to recognize the “perfect interfusion” relationship among the items of the threefold truth—namely, that each truth inherently encompasses the other two, and all three are simultaneously and inseparably present in a single moment of consciousness. This non-obstructed, interpenetrating relationship is summarized by the following principle: “To articulate one is [to encompass] all three; the complete three are none other than one” (舉一即三，全三是一).14

During the Northern and Southern Dynasties, Nirvāṇa School scholars extracted the “three dots of the character Yi” from the Mahāparinirvāṇa sūtra to articulate the profound meaning of the Mahāyāna Nirvāṇa doctrine. The Tiantai school advanced this further by utilizing the Yi-character to represent the perfectly interfused relationships inherent in all triadic dharmas, characterizing the relationships as neither sequential nor parallel, following a pattern of “one [encompassing] three, and three [being identical to] one” (一三、三一).

4. The Huayan School’s Integration of “The Three Chan Lineages” and “The Three Doctrinal Teachings”

Influenced by the Tiantai school’s extensive development of the “all triadic dharmas” framework, many scholars within the Huayan school also frequently engaged with the metaphor of Yi-character. A prominent example is Chengguan 澄觀 (738–839), retrospectively the Fourth Patriarch of the Huayan school, whose philosophy was deeply shaped by Tiantai thought. In his exegesis of the Flower Ornament Sūtra (Huayan jing 華嚴經), Chengguan employed the symbolism of a single Yi-character separating into three dots and three dots merging back into a single Yi-character to illustrate the perfectly interfusion relationship between the “Three Vehicles” (triyāna) and the “One Vehicle” (ekayāna).15

Notably, Chengguan also observed that the Yi-character could be written in two forms: not only as “∴” but also as “∵.” He argued that both forms were valid, stating, “One cannot rigidly assign a fixed order or hierarchy [to the dots] (lit. ‘one or two, above or below’); and instead grasp that [their relationship] is neither vertical nor horizontal, neither merged nor separate.”16 This perspective clearly diverged from that of the Northern and Southern Dynasties Nirvāṇa scholars, who emphasized a “substance generating function” framework. In Chengguan’s view, since each dot inherently encompasses the other two, there is no fixed distinction between substance and function among the three dots. Therefore, whether the Yi-character is written with one dot on top or two dots on top, it equally effectively symbolizes the relationship of “perfect interfusion.”

Among Huayan monks, the application of the “three dots of the character Yi” was particularly innovative in the work of its Fifth Patriarch, Guifeng Zongmi 圭峰宗密 (780–841). As a dual inheritor of both the Heze Chan 菏澤禪 and the Huayan school, Zongmi’s sectarian orientation was primarily characterized by reconciling the Chan practice with doctrinal teachings. Based on his commentaries on the Sūtra of Perfect Enlightenment (圓覺經 Yuanjue jing), he established a philosophy of “Huayan-Chan” that integrated the “Four Dharma Realms” (si fajie 四法界) into the “One Mind” (yixin 一心). In his major writings, Zongmi typically employed the Yi-character metaphor within the context of the perfect interfusion of the “Three Virtues of Nirvāṇa” and “all triadic dharmas.” Furthermore, he also utilized this symbol to advance his thesis of the unity of Chan and the doctrinal teachings, thereby imbuing the “three dots of the character Yi” with additional hermeneutical significance related to the doctrinal classification (panjiao 判教).

“Doctrinal Classification” is a tradition unique to Chinese Buddhism.17 Among the most influential classification systems are Zhiyi’s “Five Periods and Eight Teachings” (wushi bajiao 五時八教) and Fazang’s “Five Teachings and Ten Schools” (wujiao shizong 五教十宗). Both are interpretive frameworks that classify and evaluate the various schools of Hīnayāna and Mahāyāna Buddhism. Zongmi’s classification doctrine, on the one hand, inherited the basic structure of Fazang’s system, which categorized teachings as “Hīnayāna, Initial, Final, Sudden, and Perfect.” On the other hand, Zongmi introduced significant innovations in response to the intellectual shifts of his time. During Zongmi’s era, the Huayan school was beginning to decline from its peak of influence, while the Chan school was experiencing rapid growth alongside internal sectarian fragmentation. Simultaneously, Confucianism was gaining momentum towards a revival, propelled by movements like the Classical Prose Movement (guwen yundong 古文運動) led by figures such as Han Yu 韓愈 (768–824). In this context, Zongmi aimed to harmonize doctrinal teachings with Chan practice, consolidate forces within Buddhism, and counter the rising influence of Confucianism.

Preface to the Collection of Chan Sources (Chanyuan zhuquanji duxu 禪源諸詮集都序) is Zongmi’s seminal work dedicated to harmonizing doctrinal teaching and Chan practice. Regarding the sectarian divisions within the Chan school of his time, Zongmi expressed the following view:

Thus, followers of the Sudden and Gradual approaches regard each other like sworn enemies; those within the Southern and Northern schools oppose each other like [the rival states of] Chu and Han. The admonition of [the Buddha] washing his feet [after being insulted by a Brahmin], and the parable of the blind men touching the elephant, are precisely validated by this situation. Now, the purpose of my writing is certainly not to create yet another separate collection, but rather to synthesize them. The essential task lies in [achieving the harmony of] the three dots of the character Yi. Just as the three dots, if kept separate, can no longer form the Yi-character, so too if the three lineages [of Chan] remain in conflict, how can one accomplish Buddhahood?

故頓漸門下相見如仇讎，南北宗中相敵如楚漢。洗足之誨，摸象之喻，驗於此矣。今之所述，豈欲別為一本？集而會之，務在伊圓三點。三點各別既不成伊，三宗若乖焉能作佛？18

The “three lineages of Chan” (Chan sanzong 禪三宗) were delineated according to the Northern/Southern and Sudden/Gradual distinctions. Within the Chan community, these factions engaged in incessant mutual criticism. Zongmi employed the metaphor of the “three dots of the character Yi” to demonstrate his stance of unifying these various lineages. He argued that, just as the three separate dots cannot form the Yi-character, so too if the three Chan lineages remain independent, none can individually lead to the attainment of Buddhahood. This illustrates that Zongmi’s use of the Yi-character metaphor emphasized the necessity of harmonious integration and interpenetration among all elements within a holistic system. Similarly, regarding the doctrinal teachings, Zongmi classified them into “three types of teaching” (jiao sanzhong 教三種), which he meticulously paired one-to-one with the three Chan lineages. This pairing was intended to create a mutual “support and convergence” (fuhui 扶會) between doctrinal learning and Chan practice.

It is noteworthy that Zongmi did not include the Flower Ornament Sūtra—the scripture most highly revered by the Huayan school—within his frameworks of the “three Chan lineages” or the “three types of teaching.” Within the Huayan tradition, the doctrine of the Flower Ornament Sūtra is considered to transcend the Three Vehicles and is designated as the “Distinct Teaching of the One Vehicle” (biejiao yisheng 別教一乘), which inherently encompasses and subsumes all Chan and doctrinal lineages.19 Based on this, we may posit that, if the “one-three / three-one” (一三、三一) relationship of the “∴” symbol is used to represent the overall structure of Zongmi’s doctrinal classification, then the three Chan lineages and the three types of teaching, after being meticulously paired, constitute the individual dots of the Yi-character’s three dots, respectively. The Huayan teaching, however, occupies the position of the “comprehensive and whole One,” which integrates and underlies the three.

5. The Early Caodong School: “The Three Dots of the Perfect Yi Distinguish Host and Guest”

From the late Tang to the Five Dynasties period, the Chan school stemming from Huineng 慧能 (638–713) differentiated into five factions, known as “one flower opening into five petals.” Among these, the Caodong school, founded by Dongshan Liangjie 洞山良价 (807–869) and Caoshan Benji 曹山本寂 (840–901), also employed the tradition of using the three dots of the character Yi to express its core doctrines. Master Dongshan inherited the Song of the Precious Mirror Samādhi (Baojing sanmei ge 寶鏡三昧歌) from Yunyan Tansheng 雲岩曇晟 (782–841), and it became one of the central texts of the Caodong school. The Literary Chan of the Stone Gate (Shimen Wenzi Chan 石門文字禪) records a reference to “Yunyan’s Precious Mirror Samādhi,” which states:

The Precious Mirror responds freely, beyond secret transmission;

The slightest leakage [into conceptualization] falls into verbal explanation.

The three dots of the perfect Yi distinguish host and guest;

Subtly embracing dual illumination, it transcends correctness and deviation.

寶鏡當機不密傳，

纖毫滲漏墮言詮。

圓伊三點分賓主，

妙挾雙明絕正偏。20

Within the Caodong tradition, the categories of “guest” (bin 賓) and “host” (zhu 主) are frequently employed to denote the relationship between “substance” and “function” (tiyong 體用), particularly the relationship between the ontological ground of Buddha-nature and the myriad phenomena of the empirical world. However, in contrast to the Nirvāṇa masters of the Northern and Southern Dynasties, who emphasized “function arising from substance,” the masters of the Caodong school prioritized “realizing substance through function.” This approach involves contemplating the ultimate reality through all phenomena encountered in the everyday world.

The public case (gong’an 公案) of Master Dongshan “seeing his reflection while crossing water” serves as a prime example. Dongshan had been learning under Yunyan but failed to grasp the essential principle. While crossing a river one day, he caught sight of his own reflection in the water and suddenly experienced a great awakening. He then composed a verse, which stated:

Beware! Seek not from others,

Lest it distantly drift apart from me.

Now I journey alone,

Yet everywhere I encounter it.

It now is precisely me,

Yet I now am not it.

One must comprehend in this manner,

To finally accord with Suchness.

切忌從他覓，迢迢與我疎。

我今獨自往，處處得逢渠。

渠今正是我，我今不是渠。

應須恁麼會，方得契如如。21

In the poem, the “I” that searches everywhere for Buddha-nature represents the subjective self within the phenomenal world, while the “it”—reflected image in the water—symbolizes the originally inherent Buddha-nature. Hence, we have the lines: “everywhere I encounter it” and “It now is precisely me.” Through self-reflection upon the water, Buddha-nature is presented in an objectified form. However, this objectified grasp of Buddha-nature, much like understanding it through intellectualized or analytical means, remains merely a relative form of recognition. True awakening should occur precisely within the phenomenal “I,” realizing the inherent Buddha-nature. After this awakening, the “I” is no longer an objectified substance; hence, we have the line: “Yet I now am not it.” In this sense, the awakened person achieves a harmonious unity between the phenomenal self and the self as Buddha-nature. This is the correct path to attaining Buddhahood. Given that the Caodong school emphasizes the mutual forgetting of guest and host (binzhu liangwang 賓主兩忘) and the correspondence of substance and function (tiyong qihe 體用契合), the relationship between substance and function symbolized by “the three dots of the perfect Yi distinguish host and guest” in Yunyan’s Precious Mirror Samādhi can be illustrated as shown in Figure 1.

The latter line, “Subtly embracing dual illumination, it transcends correctness and deviation,” also exhibits a similar structure, as shown in Figure 2.

Within the discourse system of the Caodong school, “correctness” (zheng 正) and “deviation” (pian 偏) typically refer to “principle” (li 理) and “phenomena” (shi 事), respectively. “Transcending correctness and deviation” (jue zhengpian 絕正偏) thus signifies surpassing the opposition between principle and phenomena, emptiness and existence, and thereby attaining the state where principle and phenomena are perfectly interfused (lishi yuanrong 理事圓融), and defilement and purity are non-dual (ranjing bu’er 染淨不二).

In the Verse of the Five Ranks of Lord and Vassal (Wuwei junchen song 五位君臣頌) composed later by Dongshan, this central theme was developed into the more complex system of the “five ranks of deviation and correctness” (pianzheng wuwei 偏正五位), also known as the “five ranks of lord and vassal” (junchen wuwei 君臣五位), which further delineates stages of practice. Across both the threefold and fivefold relationships of deviation and correctness, the highest form is regarded as “simultaneous integration” (jiandai 兼帶), also termed the “union of the way of lord and vassal” (junchen dao he 君臣道合). According to Caoshan Benji’s explanation, “‘Simultaneous integration’ means mysteriously responding to all conditions without following after any existents. It is neither defiled nor pure, neither correct nor deviant. Therefore, it is called the ‘vast and profound great way’, the ‘true doctrine of non-attachment’.”22 Thus, the state of “simultaneous integration” carries not only the meaning of “transcendence” but also that of “responsive adaptation.” It signifies that the awakened person can, at any time and in any place, perceive the empty and quiescent nature within each and every phenomenon of the realm of form.

6. Fang Yizhi’s Reform of the Three Dots of the Character Yi

As previously indicated, within the Chinese Buddhist tradition, the symbol “∴” was initially referred to as the “three dots of the character Yi” (yizi sandian 伊字三點) or simply the “Yi-character” (yizi 伊字). Following the infusion of the connotation of “perfect interfusion” (yuanrong 圓融) by Tiantai and Huayan scholars during the Sui and Tang dynasties, this symbol later became more commonly known as the “perfect Yi” (yuanyi 圓伊/∴) or the “three dots of the perfect Yi” (yuanyi sandian 圓伊/∴三點). Within Fang Yizhi’s philosophical vocabulary, the concept he most frequently employed was that of the “Perfect ∴.” The character “圓” should be understood in the sense of “perfect interfusion,” demonstrating his acceptance of the traditional Buddhist interpretation. However, his choice to use the graphic symbol “∴” instead of the phonetic character “伊” (yi) stemmed from a unique consideration: to introduce the image and number (xiangshu 象數) of the Zhouyi and thereby reformulate the three dots of the Yi-character.

Incorporating the Zhouyi to expound Chan did not originate with Fang Yizhi. Viewed from the tradition of the Caodong school, the ideas of image and number from the Zhouyi were introduced as early as its founding period. Two examples suffice to illustrate this. First, Dongshan Liangjie proposed in the Song of the Precious Mirror Samādhi: “The doubled Li hexagram’s six lines; Deviation and Correctness mutually integrate. Stacked, they become three; Through transformation, they are exhausted as five.”23 This uses the “doubled Li” (chongli 重離) hexagram from the Zhouyi to explain the Caodong concept of “Deviation and Correctness.” The doubled Li hexagram is composed of two trigrams symbolizing “fire” (☲), stacked one upon the other to form a hexagram of six lines (䷝). These six lines can undergo a process of change through three transformations, ultimately generating a total of five hexagram images, including the doubled Li hexagram itself. Master Dongshan believed that this principle of change inherent in the Li hexagram’s symbolism corresponded to the internal structure of the Caodong “five ranks of lord and vassal.”

A second prominent example comes from his successor, Caoshan Benji. In his work, the Essential Formula of the Five Ranks (Wuwei zhijue 五位旨訣), Master Caoshan directly introduces five hexagrams from the Zhouyi—Daguo 大過 (䷛), Zhongfu 中孚 (䷼), Xun 巽 (䷸), Dui 兌 (䷹), and the doubled Li—right at the outset, using them to describe the respective stages of spiritual attainment represented by each of the five ranks. Among these, the doubled Li hexagram represents the highest stage, “Arriving at Within Integration” (jianzhongdao 兼中到): “‘Arriving at Within Integration’ is the doubled Li. Correctness need not be empty [i.e., absolute]; Deviation need not be solid [i.e., phenomenal]. There is neither turning away nor turning towards.”24 “Arriving at Within Integration,” along with aforementioned concepts like “Simultaneous Integration” and the “Union of the Way of Lord and Vassal,” signifies that the practitioners have not only transcended mundane dualistic thinking but is also able to dissolve themselves within all things of the conventional world.25

Beyond these early Caodong masters, Fang Yizhi’s own teacher in the Caodong school, Juelang Daosheng, also possessed profound expertise in Zhouyi studies. Daosheng not only used the Zhouyi to expound Chan, as was common among many late-Ming Chan masters, but also harbored the ambition to use the learning of the Zhouyi to synthesize the Three Teachings of Confucianism, Daoism, and Buddhism.26

6.1. The Central Five

Unlike his predecessors, Fang Yizhi’s key approach to integrating the study of the Zhouyi with Buddhism was to combine the diagram of the Perfect ∴ with the Hetu 河圖 (Yellow River chart) and Luoshu 洛書 (Luo River writing). The Hetu and Luoshu are cosmogonic diagrams that form the foundation of the image and number systems in the Zhouyi. Traditionally, the Hetu is linked to Fuxi 伏羲’s derivation of the eight trigrams, embodying a generative model of the universe through the harmonious interaction of Yin–Yang and the Five Phases. The Luoshu, with its unique magic square arrangement, exemplifies the dynamic balance and cyclical transformations central to the ZhouYi’s divinatory thinking process. Together, they provide a profound schematic synthesis—integrating image, number, and principle—that underpins the Zhouyi’s philosophical framework for understanding cosmic order and change.27 In the interpretive work on the Zhouyi, co-authored by Fang Yizhi and his father, the forms of the Hetu and Luoshu are presented as shown in Figure 3.

Such diagrams of the Hetu and Luoshu represent an interpretive model of the cosmos that became widely influential through the advocacy of Song dynasty Neo-Confucian scholars such as Shao Yong 邵雍 (1012–1077) and Zhu Xi 朱熹 (1130–1200). In these diagrams, each dot represents the number 1, and the accumulation of dots forms different numerals. Odd numbers are represented by white dots, while even numbers are depicted with black dots. The Hetu encompasses numbers 1 through 10, whereas the Luoshu includes only numbers 1 through 9. These numbers are arranged in specific spatial orientations according to distinct principles. The Hetu and Luoshu symbolize, respectively, the order of heaven and the mensuration of the earth, the generative model and the changing rule, as well as the substance and the function.

Fang Yizhi and his father placed particular emphasis on the number 5 in these diagrams—regardless of how the other numbers varied in the two charts, 5 always occupied the central position. In their view, these five dots arranged in a cross-shaped distribution symbolize the fundamental order of cosmic generation and the basic principle governing the operation of all things. Fang Yizhi and his father stated that “The center is five, its function is three; one is concealed, while four revolve—this is the standard of the Zhouyi.”29 Scholars such as Cai Zhenfeng have interpreted this statement as follows: “Both ‘the center is five, its function is three’ and ‘one is concealed, while four revolve’ take the three-dot pattern of the ∴ symbol as their basic form. In the ∴ symbol, the central dot remains fixed, while the other two dots rotate to form the ∵ symbol. By combining the ∴ and ∵ symbols, four ∴ patterns are formed—above, below, to the left, and to the right.”30 Consequently, Fang Yizhi sometimes combined the “Perfect ∴” with the Hetu and Luoshu, referring to them collectively as the “Perfect ∴ Chart and Writing” (yuanyi tushu 圓∴圖書).31

By integrating with the central five dots of the Hetu and Luoshu, the symbol “∴” acquired a significant cosmological meaning that it originally did not possess within the Buddhist tradition. This symbol thus came to represent a basic model of the universe. Although they were promoted by the Tiantai and Huayan schools, the three dots of the character Yi—while symbolically representing “all triadic Dharmas”—are essentially illusory and insubstantial in their Perfect Interfusion. This is based on the Mahāyāna doctrine of “emptiness” of all phenomena. Although Fang Yizhi became a Chan master in his later years, he never accepted the Buddhist assertion that the nature of all existence is fundamentally empty. It can be said that Fang Yizhi’s adoption of the Buddhist concept of the three dots of character Yi was merely an absorption of its conceptual mode. In his view, the cosmic vision was always grounded in a Confucianized interpretation of the Zhouyi, portraying a universe that possesses an inherent “reason of being” as its axiological foundation and is perpetually dynamic and generative in its manifested existence.

6.2. The Great Ultimate—Two Modes

Fang Yizhi also endowed the symbol “∴” with the basic principles of the Zhouyi—namely, the “Great Ultimate” (taiji 太極) and the “Two Modes” (liangyi 兩儀):

The three dots of the Perfect ∴ exemplify the principle of presenting one to illuminate three, which signifies employing the mean between two extremes and permeating all with a single unifying principle. Essentially, all phenomena arise from the duality of odd and even numbers, wherein the odd and the even constitute the foundation of the triadic and dyadic relationships. The upper dot represents the Great Ultimate, which transcends all dualities and eludes the four propositions of logical assertion. The lower two dots represent the Two Modes, which exist in mutual opposition and interact through alternating rotation within the Great Ultimate. […] The symbol is conceived in this way, with the upper dot actually penetrating the two lower dots like a circle, neither vertical nor horizontal, yet capable of being both vertical and horizontal.

圓∴三點，舉一明三，即是兩端用中，一以貫之。蓋千萬不出於奇偶之二者，而奇一偶二即參兩之原也。上一點為無對待、不落四句之太極，下二點為相對待、交輪太極之兩儀。……設象如此，而上一點實貫二者如環，非縱非橫而可縱可橫。32

The term “Two Modes” referred to the solid line (yangyao 陽爻) and broken line (yinyao 陰爻) in the Zhouyi, as stated in the Xici zhuan 繫辭傳 (Commentary on the Appended Phrases): “In the Changes, there is the Great Ultimate, which generates the Two Modes. The Two Modes generate the Four Images, and the Four Images generate the Eight Trigrams.” (易有太極，是生兩儀。兩儀生四象，四象生八卦。) Fang Yizhi interpreted the “Two Modes” as all mutually opposing phenomena: “the substantial and the insubstantial, movement and stillness, Yin and Yang, form and material, principle and concrete reality, day and night, the hidden and the manifest, life and death—all [the things] in heaven and earth, past and present, are dual.”33 All concrete and abstract existence can be distinguished into two opposite aspects. However, due to the presence of the Great Ultimate, the two opposing ends continuously move toward each other, engaging in an unceasing process of mutual transformation, much like the unending alternation of day and night. The two mutually opposing aspects originate from a single source, and after generating a pair of opposites, this source exists within that pair of opposites. The Great Ultimate, as the dynamic source of perpetual generation, enables the Two Modes to undergo constant mutual transformation. Opposites arise from the same source and, under the influence of this source, continuously transform into each other. This relationship is termed by Fang Yizhi as “mutual opposition and mutual causation” (xiangfan xiangyin 相反相因).

The relationship between the Great Ultimate and the Two Modes, as symbolized by Fang Yizhi’s Perfect ∴, can be understood through the diagram shown in Figure 4.

It can be intuitively observed that, unlike the planar configuration formed by the three dots of the character Yi in earlier Buddhist thought, Fang Yizhi’s description of “the upper dot actually penetrating the two lower dots like a circle” results in a three-dimensional conical structure. Furthermore, the relationship he describes among the three dots as “neither vertical nor horizontal, yet capable of being both vertical and horizontal” differs from the principle of Perfect Interfusion emphasized in Tiantai Buddhism. If Tiantai master Zhiyi’s notion of “neither vertical nor horizontal” was formed with the primary aim of illustrating that each of the three dots encompasses the other two, Fang Yizhi’s use of “neither vertical nor horizontal” focuses instead on the relationship between the two modes, Yin and Yang—that is, due to the dynamic presence of the Great Ultimate, the opposing forces are not isolated from each other in time or space but exist in a cyclical and transformative interplay. It can be said that Fang Yizhi’s concept of “neither vertical nor horizontal” essentially conveys the idea of “mutual opposition and mutual causation.”

Of course, this conical representation of the three dots must be premised on the differentiation of the Great Ultimate into the Two Modes. This differentiation resembles the interpretation of the Yi-character by the Nirvāṇa masters during the Northern and Southern Dynasties, where the upper dot was regarded as the “substance” (ti 體), and the lower two dots as the “function” (yong 用), suggesting that one substance gives rise to two functions. In comparison, the distinctive feature of Fang Yizhi’s Perfect ∴ lies not only in depicting the relationship of mutual opposition and mutual causation between the lower two dots but also in his repeated emphasis on “substance existing within function” (ti zai yong zhong 體在用中) and “the great duality being the great unity” (daliang ji dayi 大兩即大一), prioritizing the “function” of the “two” over the “substance” of the “one.” This is because, although the Great Ultimate, as the absolute, serves as the dynamic source of perpetual generation, it is itself beyond empirical experience. “The non-opposition exists within opposition, yet one must intimately apprehend this non-opposition.”34 Only through the experience of the mutual opposition and mutual causation of the two functions can the existence of the Great Ultimate as substance be confirmed. The respective emphases placed by the early Nirvāṇa masters and Fang Yizhi on the upper dot and the lower two dots in the ∴ schema reflect the historical shift in Chinese philosophy from prioritizing “substance” to prioritizing “function.” Liang Qichao 梁啟超 (Liang 2015, p. 150) once characterized Fang Yizhi’s scholarship as embodying three key principles: “esteeming doubt” (zun yi 尊疑), “esteeming evidence” (zun zheng 尊證), and “esteeming the present” (zun jin 尊今). Fang’s emphasis on “Function” highlights his advocacy for skeptical inquiry, and his focus on empirical evidence and contemporary changes. This intellectual orientation was consistent with the broader scholarly trend shifting toward the Evidential Learning (kaoju xue 考據學) of the Qing Dynasty.

6.3. The Three Ultimates and the Three Heavens

Fang Yizhi’s reinterpretation of the three dots of the character Yi through the lens of the Zhouyi can also be examined in conjunction with his self-devised theory of the “Three Ultimates” (sanji 三極). The original text of the Zhouyi mentions only the term “Great Ultimate.” It was not until the Song Dynasty that Zhou Dunyi 周敦頤 (1017–1073) introduced the concept of the “Ultimate of Non-being” (wuji 無極), stating, “The Ultimate of Non-being and yet the Great Ultimate.” (wuji er taiji 無極而太極) In Zhu Xi’s revised edition of the Explanation of the Diagram of the Great Ultimate (Taijitu shuo 太極圖說), the phrase “the Ultimate of Non-being and yet the Great Ultimate” does not imply that there exists a separate substance called the “Ultimate of Non-being” beyond the Great Ultimate. Rather, it signifies that the Great Ultimate possesses the characteristic of “non-being”—while all things have form and appearance, the Great Ultimate, as the source of creation, is imperceptible to the senses.

Many scholars during the Song Dynasty debated whether it was necessary to add the Ultimate of Non-being before the Great Ultimate. Fang Yizhi, however, not only acknowledged the Ultimate of Non-being but also proposed the concept of the “Ultimate of Being” (有極 youji) in addition to the Great Ultimate and the Ultimate of Non-being. His reasoning was: “If we add the Ultimate of Non-being before the Great Ultimate, we cannot reveal the Great Ultimate that transcends both being and non-being. Therefore, I propose a third term.”35 The Great Ultimate, though formless, generates things with form. After generating things, it resides within each and every phenomenon. Thus, it can be said that the Great Ultimate simultaneously embodies the characteristics of both being and non-being, or conversely, that it is confined neither to “having form” nor to “being formless.” Hence, the first structural feature of Fang Yizhi’s theory of the “Three Ultimates” is that the “Great Ultimate transcends both being and non-being.” By introducing the “Ultimate of Being” as a counterpart to the “Ultimate of Non-being,” the Great Ultimate maintains its status as the “non-oppositional” substance, and the relationship among the Three Ultimates forms a “∴” schema.

The second structural characteristic of the theory of the Three Ultimates is formed through its integration with the theory of the “Three Heavens.” Shao Yong, the most famous Zhouyi scholar in the Northern Song Dynasty, used the Hetu and Luoshu to represent the innate (xiantian 先天) and the acquired (houtian 後天) realms, respectively. Fang Yizhi posited that the innate and acquired realms are mutually opposing, while introducing his self-devised concept of the “Central Heaven” (zhongtian 中天), which transcends both the innate and acquired realms, thereby forming another “∴” schema. Fang Yizhi states:

The hexagrams and lines of the acquired realm are already fully manifested—this is called the Ultimate of Being. The hexagrams and lines of the innate realm have not yet been fully expressed—this is called the Ultimate of Non-being. These two Ultimates stand in opposition, while the absolute Great Ultimate, transcending opposition, is called the Central Heaven. The Central Heaven exists within both the innate and acquired realms, and the innate realm exists within the acquired realm—thus, the three are one.

後天卦爻已布，是曰有極；先天卦爻未闡，是曰無極。二極相待，而絕待之太極，是曰中天。中天即在先、後天中，而先天即在後天中，則三而一矣。36

Although this passage does not directly mention the “Perfect ∴,” it is evident that the distribution of the Three Ultimates and the Three Heavens inherently follows the structure of a non-oppositional upper point and two opposing lower points. Particularly noteworthy is Fang Yizhi’s emphasis that “the Central Heaven exists within both the innate and acquired realms, and the innate realm exists within the acquired realm,” indicating that his focus lies on the “Acquired Realm” and the “Ultimate of Being.” This can be illustrated as shown in Figure 5.

Comparing the above diagram with the Caodong School’s schematic of “Deviation, Correctness, and Simultaneous Integration,” it becomes evident that both share a similar structural distribution and reasoning process. The difference, however, lies in the fact that the Caodong School’s three dots of the Perfect Yi emphasize deriving the “simultaneous integration” from the “deviation,” whereas Fang Yizhi reverses this approach, stressing the derivation of the “Ultimate of Being” from the “Great Ultimate” and the “Acquired Realm” from the “Central Heaven.” The Ultimate of Being and the Acquired Realm represent the dynamic, hierarchically structured, and orderly real world.

In Fang Yizhi’s view, both Confucianism and Buddhism in the late Ming Dynasty had fallen into the same trap of impracticality and abstraction: “Chan Buddhists observed Confucians immersed in worldly affairs and considered it unproblematic, thereby reducing Chan to a teaching that dismisses cause and effect. Confucians, in turn, borrowed the Chan notion of perfect interfusion and claimed it as an unprecedented insight, thus turning Confucianism into a doctrine of unbridled audacity.”37 Discourses such as “perfect interfusion” (yuanrong 圓融) and “unobstructed” (bu’ai 不礙) had become excuses for late Ming Confucians and monks to neglect social norms, undermine their ethical relationships, and avoid reading and learning. To counteract this trend, Fang Yizhi particularly emphasized the Buddhist spiritual tradition that “Perfect interfusion does not obstruct sequential deployment” (yuanrong bu’ai xingbu 圓融不礙行布), highlighting the importance of the empirical world and the concrete order of reality.38

7. Conclusions: The Perfect ∴ as the Conceptual Foundation for the Interconnectedness of the Three Teachings

Although the three dots of the Perfect ∴ form an inseparable unity, each possesses its distinct function. Depending on the situation, different spiritual connotations should be emphasized to rectify the deviations of the era. Fang Yizhi believed this to be the essence of the Caodong School’s principle of “Simultaneous Integration.” He stated: “Most people fail to understand the alternating interplay of the Perfect ∴, and thus cannot comprehend the subtlety of its integrative nature that embodies neither fixed affirmation nor fixed negation.”39 The term daicuo 代錯 (“alternating interplay”) originates from the Doctrine of the Mean (Zhongyong 中庸): “Just as the four seasons proceed in alternating sequence, and as the sun and moon illuminate in revolving succession.” (辟如四時之錯行，如日月之代明。) Correspondingly, human conduct should also adapt and adjust in accordance with the times. By the late Ming period, mutual imitation among the Three Teachings (Confucianism, Buddhism, and Daoism) led to numerous disorders: monks disregarded monastic rules and excessively engaged in secular life, while Confucian scholars adopted Chan Buddhist practices such as iconoclasm and transcending language, resulting in neglect of Confucian classics and a lack of substantive learning. In such a context, the spirit of “perfect interfusion,” which transcends all oppositions, had been taken to extremes. Instead, it became necessary to promote the spirit of “sequential deployment” (xingbu 行布), which emphasizes distinctions, order, and rules, thereby clarifying the boundaries among the Three Teachings.

The Three Teachings should strictly adhere to their respective traditions while simultaneously achieving harmonious coexistence. The secret of this, in Fang Yizhi’s view, lies in the fact that the core doctrines of all Three Teachings conform to the cosmic principle represented by the Perfect ∴ schema. That Buddhism and the Zhouyi align with this principle is self-evident; Fang Yizhi also repeatedly demonstrated that the philosophical thinking of Confucius, Laozi, and Zhuangzi inherently embodies the Perfect ∴ mode of thought. For instance, he stated: “When examined through the lens of the Perfect ∴’s principle of ‘raising one to illuminate three’, one immediately understands the Confucian method of ‘grasping the two extremes to apply the Mean’ and ‘permeating all with a single unifying principle’.”40 This references the Zhongyong’s “grasping the two extremes and applying the Mean for the people” (執其兩端，用其中於民) and the Analects’ “My way is permeated by a single unifying principle” (予一以貫之), thereby characterizing Confucius’s philosophy.

In terms of Daoism, Fang Yizhi argued the following: “Laozi said: ‘Reversion is the movement of the Dao.’ The character fan 反 here signifies more than just ‘return’ (fu 複). […… but implies that] in the immediate moment, one realizes that the opposing cause is simultaneously the fundamental cause.”41 Here, he interprets Laozi’s concept of “reversion” through the lens of “mutual opposition and mutual causation”, intrinsic to the ∴ schema. As for Zhuangzi, Fang Yizhi coined the phrase “the Perfect ∴ and the axis of the ring” (yuanyi huanzhong 圓∴環中)42, thereby incorporating Zhuangzi’s model of “only as the pivot attains the center of the ring” (樞始得其環中) into this triadic structure. Fang Yizhi’s critical engagement with Daoist philosophy culminated in his work Yaodi pao Zhuang 薬地炮莊 (The Medicinal Herbs Master’s Stewing of the Zhuangzi), composed after he entered monastic life. Building upon teacher Daosheng’s Zhuangzi tizheng 莊子提正 (Rectifying Interpretations of the Zhuangzi)43, Fang integrated public cases of Chan and the image and number from the Zhouyi to interpret Zhuangzi. He sought to demonstrate that Zhuangzi’s thought aligned with the Buddhist spirit of “dissolving attachments” while simultaneously advocating for the theory that “Zhuangzi emerged from the Confucianism”44.

In summary, the core doctrines of the Three Teachings all adhere to the cosmic principle of the Perfect ∴, enabling them to coexist without conflict. Simultaneously, due to their distinct historical traditions and emphases on different spiritual orientations, they cannot be conflated. The model of interrelationship among the Three Teachings advocated by Fang Yizhi essentially requires a comprehensive perspective that transcends the individual teachings themselves, allowing them to harmoniously coexist while preserving their respective independence. Fang Yizhi’s approach to reconciling the Three Teachings was unique in the late Ming context45 and likely drew considerable inspiration from the Perfect ∴ model inherent in Zongmi’s framework of doctrinal classification.