A Study on the Philosophy of Perfect Harmony in the Huayan School: Focusing on the Four Dharmadhātus

Abstract

The philosophy of the Huayan school is founded on the dharmadhātu (法界) as its fundamental ontology, embodying the boundless truth of the cosmos and human existence. It seamlessly integrates the philosophical doctrine of the “perfect interpenetration and non-obstruction of Buddhist teachings”, while expounding the vast tenets of “principle (理), phenomena (事), wisdom (智), and practice (行),” all of which are encompassed within the comprehensive framework of the “four stages of faith–understanding–practice–realization (信解行证)”. The idea of “four dharmadhātus” (四法界), which was first systematically formulated by Master Chengguan, is considered one of the core doctrines of Huayan thought. However, contemporary scholarship has yet to provide a thorough elucidation of the relationship between the one true dharmadhātu (一真法界) and the four dharmadhātus, nor has it sufficiently addressed the notion that the four dharmadhātus are not merely a theoretical construct but also a genuine realization—a stage in the practice of spiritual cultivation. This study first explicates the conceptual significance of the four dharmadhātus, then analyzes the Huayan patriarchs’ interpretations of the one true dharmadhātu and the four dharmadhātus. It further explores the path to awakening through the interpenetration and non-obstruction of the four dharmadhātus and highlights the integration between the empirical world and the ideal world of Buddhist teachings. Ultimately, it argues that every realm and every stage within the dharmadhātu is perfectly complete and seamlessly interconnected.

1. Introduction

The Avataṃsaka Sūtra (Huayan jing, 華嚴經) is one of the foundational scriptures of Mahāyāna Buddhism. It directly elucidates the definitive teachings of the Mahāyāna tradition. The doctrinal coherence and comprehensive insight of the Huayan school are grounded in the theory of the four dharmadhātus1. As Oh notes, “From its canonical scripture, the Avataṃsaka Sūtra, the Huayan school derived the idea of dharmadhātu as the central theme for teaching and meditation” (Oh 1976, p. 5). Being one of the core teachings of the Huayan school, the concept of “four dharmadhātus” attracts much attention from researchers. There have been a considerable number of works on the philosophy of the Huayan Buddhism. It is generally held among researchers that the doctrine of the four dharmadhātus in the Huayan school was first articulated by Master Chengguan (澄觀大師, 738–839) (Zhenghe Yang 1992, p. 440; Wei 2008, p. 180; Kimura et al. 2011, p. 195; Kamekawa and Hai 2018, p. 149), and Zengwen Yang (2019, p. 8) remarks the following: “In order to make this profound vision of the dharmadhātu more comprehensible, Master Chengguan synthesized Master Dushun’s threefold view of the dharmadhātus and Master Fazang’s fivefold dharmadhātus, thereby distilling them into the four dharmadhātus”. However, even some book-length studies make little reference to the idea of the four dharmadhātus and seamless and un-obstructed integration (Park 2008; Cook 2010). Other works contain only a brief discussion of these issues, which indicates that this is still an under-explored field in Huayan Buddhism.

For example, Chang (1971) highlights the interdependence of Li and Shi, stating that they form a unified whole and are inseparable. He provides the foundational understanding of the four dharmadhātus, emphasizing the dynamic and non-dual relationship between principle and phenomena. This supports the idea of a system of harmonious and un-obstructed integration. Oh (1976) provides an in-depth study of Chinese Huayan Buddhism with special reference to the dharmadhātu doctrine, and discusses the philosophical and religious significance of the dharmadhātu doctrine, as well as its historical influence. In addition, he considers Huayan Buddhism as the most theoretical and systematic presentation of Buddhist ideas in China. Oh (1979, pp. 72–91) provides the basic etymology and meanings of dharmadhātu, which is a foundational concept in Huayan Buddhism related to elements, constituents, and existence, and he highlights how the Huayan school systematized dharmadhātu, referencing Master Dushun’s (杜順大師, 557–640) insights and Master Fazang’s (法藏大師, 643–712) theoretical contributions. Cleary (1983) describes Master Dushun’s exploration of the four dharmadhātus, including the noninterference of noumenon and phenomena as key aspects of Huayan metaphysics. Odin (1983) identifies four distinct levels of dharmadhātu, aligning them with stages of theoretical understanding, and he interprets emptiness (sunyata) in Huayan as signifying the profound interdependence and interpenetrative character of events, highlighting ontological fullness. Gregory (1983, pp. 253–20) does not explicitly discuss the four dharmadhātus in the Huayan school. However, he does discuss elements that can be related to understanding and practice within the Huayan framework, particularly concerning the integration of principle and phenomena, and the path to enlightenment. For example, the practices of maintaining precepts, meditation, and moral conduct directly influence one’s ability to realize the nature of reality as described by the four dharmadhātus. Gimello (1983, pp. 321–87) mentions the realization that one’s own body and mind are fundamentally the dharmadhātu. This is relevant to achieving the realization of one’s true nature. Shim (1987, pp. 49–64) emphasizes Master Fazang’s logic of “non-obstruction among events (shi-shi wu-ai)”, indicating that any stage can be identified with all other stages. Hamar (1998, pp. 1–19) focuses specifically on Master Chengguan’s theory of the four dharmadhātus, and explains Master Chengguan’s view that the dharmadhātu is identical to the essence of one mind. Jiang (2001, pp. 457–75) provides a detailed examination of the Li/Shi relationship and the concept of interpenetration, which are central to the four dharmadhātus. The explanation of the relationship of one and all is central to understanding the scope of the four dharmadhātus. Ben (2002, pp. 169–84) mentions the Huayan school’s concept of “the four dharmadhātus”, but the discussion is focused solely on Master Chengguan’s interpretation of this concept. Park (2003, pp. 165–74) emphasizes the Huayan principle that “each particle of dust contains the entire world,” indicating the interconnectedness of all phenomena. This concept aligns with the seamless integration of principles and phenomena studied in this paper. Plassen (2007, pp. 1–19) highlights how Master Dushun’s use of Li and Shi represents a more positive evaluation of the phenomenal world as an expression of reality, and mentions that Imre Hamar has forwarded a series of publications on Master Chengguan’s biography and the diverse aspects of his thought, including his theory of the four dharmadhātus. Jones (2010, pp. 355–68) notes that in Buddhist thought, all objects are considered insubstantial processes or events, eliminating the contrast between objects and events. Hamar (2014, pp. 145–65) positions the four dharmadhātus as a synthesis of the school’s core tenets and points out that all phenomena have a common origination from the absolute mind. What is more, he explains that the dharmadhātu of non-obstruction of phenomena can be established because all phenomena are endowed with absolute nature. Van Norden and Jones (2019) provide a detailed overview of the Huayan school, including the development of the four dharmadhātus by Master Chengguan. They describe Li Tongxuan’s (李通玄, 635–730) teaching of the one true dharmadhātu as one where all places and objects are as true as they are. Plassen (2023, pp. 133–48) emphasizes the importance of meditative practice in understanding Huayan philosophy and highlights the role of emptiness as the foundation for the interpenetration of all things, and suggests that the concepts of the four dharmadhātus may be better understood as a means of meditative practice than a metaphysical system. Xiong (2024, p. 482) emphasizes that all things are interdependent, interpenetrating, and un-obstructed in the dharmadhātu, and highlights the importance of the mind in Huayan thought, stating that all dharmas turn from the mind and are formed by it. What is more, he connects these doctrines to the practical goal of achieving bodhi and nirvana.

Through the study of the relevant literature, it becomes evident that a conclusive exposition on the relationship between the one true dharmadhātu (一真法界, yizhen fajie) and the four dharmadhātus (四法界) remains lacking. In essence, the one true dharmadhātu and the dharmadhātu itself share a relationship of “wondrous existence within true emptiness and true emptiness within wondrous existence”. The entirety of the four dharmadhātus, even in their ultimate standpoint, represents nothing other than the singular and genuine dharmadhātu—the one true dharmadhātu, which embodies the intrinsic awakened nature of the Buddha. Therefore, only the one true dharmadhātu can encompass and unify any dharmadhātu. Likewise, the one true dharmadhātu and the four dharmadhātus are not two, but are fundamentally one in nature. Furthermore, the literature also discusses the practical cultivation corresponding to the four dharmadhātus. However, as the ultimate doctrinal expression of the Huayan tradition, the four dharmadhātus are not merely theoretical constructs but embody a genuine view of realization. This genuine view is identical to the stage and labor of spiritual practice. When such a realization becomes clear and self-liberated, one naturally knows how to act. Otherwise, even with seemingly intellectual comprehension, one’s realization remains obstructed at the level of the mind-ground. In truth, the dharmadhātu is Buddha, and the Buddha is the dharmadhātu. The practitioner, too, is the entirety of the dharmadhātu—his mind is the complete dharmadhātu, his body likewise the complete dharmadhātu. This path of awakening does not necessarily require gradual entry; this is what is referred to as sudden awakening (頓悟): an immediate entry into the dharmadhātu of non-obstruction of phenomena and phenomena. One may enter directly through any dharmadhātu into this ultimate dharmadhātu, for each and every dharmadhātu is in essence the one true dharmadhātu—complete, perfect, freely accessible, and fully integrated, with no obstruction whatsoever.

This paper, building on a detailed exposition of the philosophy of “the four dharmadhātus” as a system of harmonious and un-obstructed integration, seeks to clarify the internal development of this doctrine, to integrate and interpret the definitive teachings (liǎoyì, 了義) of Mahāyāna Buddhism, and to focus on its articulation of the path to enlightenment. At the level of doctrinal and meditative realization, research into the integrative nature of the four dharmadhātus reveals the supreme importance of the one mind (一心) as the absolute ontological ground. In this sense, the religious significance of the Huayan view of the dharmadhātu lies in its ability to bring lofty ideals into concrete religious practice in the lived world. This integration is subtle and profound—it reflects a seamless interface between the realm of philosophical insight and that of existential embodiment, demonstrating the ultimate interpenetration of the phenomenal and the ideal worlds. Such a realization leads beings to deeply comprehend the teaching that “the Dharma is in the world” (佛法在世間) [Zongbao 宗寶, The Platform Sūtra of the Sixth Patriarch 六祖大師法寶壇經, Chapter on Prajñā 般若品, Taishō Tripiṭaka 大正藏, vol. 48, p. 351]. Through rigorous study of the Huayan doctrine of the four dharmadhātus, one can gain a deeper appreciation of the statement that “The entire sūtra does not depart from the four gates of faith, understanding, practice, and realization; this is the very structure by which the teaching functions” (一部經, 不出信解行證四門, 此乃能詮之教) [Master Fu’an 復庵和尚, The Systematic Outline of the Avataṃsaka Sūtra 華嚴經綸貫, 1986, p. 4.]. This recognition enables a more grounded grasp of the practical path laid out through faith–understanding–practice–realization (信解行證) and opening–revealing–awakening–entering (開示悟入), thereby facilitating a genuine integration of doctrinal insight and lived realization—an embodied expression of the Huayan ideal of the seamless fusion between principle and phenomena.

This study undertakes a systematic clarification of the doctrinal notion of the dharmadhātu, employing philosophical analysis to elucidate the theoretical structure of the four dharmadhātus. In addition, by integrating a historical perspective, this study traces the formative and constructive process through which Master Chengguan’s theory of four dharmadhatus emerged. Accordingly, the present research integrates both a historical–philosophical approach and analytic philosophical methods to offer a comprehensive account of this pivotal Huayan concept.

2. The Doctrinal Significance of the Four Dharmadhātus in the Huayan School and Their Implications for Mind and Consciousness

The well-known doctrine of the four dharmadhātus has come to be recognized as one of the core theoretical expressions of Huayan thought. However, this doctrine did not exist in its complete form at the initial founding of the Huayan school. Rather, its theoretical construction unfolded gradually through successive generations of Huayan patriarchs, whose interpretations and elucidations shaped its development. It was ultimately Master Chengguan who systematized the teaching and, for the first time, formally articulated the doctrine of the four dharmadhātus.

Rooted in the Avataṃsaka Sūtra, the Huayan school articulates the principle of the dependent arising of the dharmadhātu (dharmadhātu-pratītyasamutpāda, 法界緣起), which reveals the wondrous and unimpeded interpenetration of all phenomena within the cosmos. As such, the integrative and non-obstructive nature of the Avataṃsaka Sūtra directly manifests the Buddhist ideal of totalistic interrelation. Following the Buddha’s enlightenment, he expounded the origins of the cosmos and human existence, a teaching later encapsulated under the doctrine of dependent origination.

Xiong (2024, p. 482) summarizes this as follows: “The ultimate goal of both the Huayan and other schools was to enable sentient beings to attain bodhi and nirvana. Therefore, the ultimate purpose of understanding the DIDCD (無盡法界緣起, the dependent arising of the infinitely diverse dharmadhātu) is also to enable sentient beings to attain bodhi and nirvana”.

It was Master Dushun who initially extrapolated the idea of dharmadhātu-pratītyasamutpāda from the Avataṃsaka Sūtra, laying the foundational thought for what would later become the doctrine of the four dharmadhātus. He also proposed the framework of the “Three Contemplations” (sanguan, 三觀): the contemplation of true emptiness, the contemplation of non-obstruction between principle and phenomena, and the contemplation of mutual containment and pervasiveness. This system was subsequently enriched and systematized by Master Chengguan, and he firstly articulated and codified the core content of the four dharmadhātus doctrine. The four dharmadhātus doctrine is actually an innovation of Master Chengguan.

With regard to the exposition of the dharmadhātu, each of the patriarchs of the Huayan school has addressed the concept in their respective commentaries. Master Zhiyan (智儼大師, 602—668) states the following: “Why is this again designated as the dharmadhātu? It is because it serves as the basis upon which all the sublime teachings of the Śrāvakas, Pratyekabuddhas, and Buddhas rely” (何故復說此名法界。一切聲聞緣覺諸佛妙法所依相故). [Master Zhiyan 智儼大師, Classified Compilation of Chapter Headings and Essential Topics in the Avataṃsaka Sūtra 華嚴經內章門等雜孔目章, vol. 1, Taishō Tripiṭaka 大正藏, vol. 45, p. 542.]. Here, Master Zhiyan understands the dharmadhātu as encompassing all aspects of reality—from the fundamental Buddha-nature to the various doctrinal teachings, as well as all sentient beings and the manifold phenomena of the world.

Master Fazang states in Commentary on the Treatise on the Non-Differentiation of the Dharmadhātu in the Mahāyāna 大乘法界無差別論疏:

“The term dharma possesses three meanings: (1) the meaning of sustaining, indicating that its self-nature remains unchanging; (2) the meaning of norm or standard, in that it serves as a model which gives rise to understanding; (3) the meaning of cognitive object, in that it is known by consciousness. The term dhatu likewise holds three meanings: (1) the meaning of cause, referring to the arising of noble dharmas...... (2) the meaning of nature, referring to the true nature of dharmas...... (3) the meaning of delimitation, in that the distinctions among dharmas remain unmixed—hence it is called dhātu. The first two are the dhātu of dharmas, thus called the dharmadhātu; the third, being itself a dhātu, is likewise named dharmadhātu.”2

[Master Fazang 法藏大師, Commentary on the Treatise on the Non-Differentiation of the Dharmadhātu in the Mahāyāna 大乘法界無差別論疏, Taishō Tripiṭaka 大正藏, vol. 44, p. 63.]

Through this exposition, Master Fazang reveals that the dharmadhātu encompasses the meanings of dharma-nature, buddha-nature, and suchness (真如). At once, it signifies the unchanging self-nature of all dharmas and their capacity to bring forth realization. Thus, the dharmadhātu is not only the ontological ground and original essence of all phenomena, but also the inclusive totality of all things and appearances.

In the Brief Commentary on the Avataṃsaka Sūtra 大華嚴經略策, Master Chengguan expounds on the dharmadhātu from the dual perspectives of Li and Shi. He maintains that the dharmadhātu expresses both the ultimate truth underlying all dharmas and the essential ground common to all sentient beings. At the same time, all worldly phenomena—the manifold appearances of things—are themselves none other than manifestations of the dharmadhātu.

In this regard, Wei (2008, p. 179) observes the following: “Master Chenguang’s discussion of the relationship between principle and phenomena, taken as a whole, does not go beyond the doctrinal scope set forth by Master Zhiyan and Master Fazang. What he accomplished was a systematic clarification and arrangement of their views, rendering them more coherent and organized. Nevertheless, his particular emphasis on the interplay between principle and phenomena is closely related to his formulation of the doctrine of the four dharmadhātus”.

This discussion must further engage with the doctrinal expositions on the dharmadhātu by Master Fazang and Master Huiyuan (慧苑大師, 673–743?)3. Master Fazang elucidates the profound connotations of the dharmadhātu, systematically differentiating it into the dharmadhātu of phenomena and the dharmadhātu of principle. Master Fazang also articulates a threefold division: “When neither essence nor attributes abide, this is the Dharmadhātu of Principle; When unimpeded by phenomenal appearances and yet fully manifest, this is the Dharmadhātu of Phenomena; When principle and phenomena interpenetrate without obstruction, the two are not-two, and the not-two is precisely two—this is the dharmadhātu” (若性相不存, 則為理法界; 不礙事相宛然, 是事法界; 合理事無礙, 二而無二, 無二即二, 是為法界也). [Master Fazang, The Hundred Gates to the Ocean of Meaning in the Avataṃsaka Sūtra 華嚴經義海百門, Taishō Tripiṭaka 大正藏, vol. 45, p. 627.]. This corresponds to the dharmadhātu of principle, the dharmadhātu of phenomena, and the dharmadhātu of non-obstruction between principle and phenomena. In addition, Fazang also proposes a fivefold classification of the dharmadhātu: “The conditioned dharmadhātu; The unconditioned dharmadhātu; The dharmadhātu that is both conditioned and unconditioned; The dharmadhātu that is neither conditioned nor unconditioned; The un-obstructed dharmadhātu” (有為法界; 無為法界; 亦有為亦無為法界; 非有為非無為法界; 無障礙法界). [Master Fazang, Commentary on the Profound Meaning of the Avataṃsaka Sūtra 華嚴經探玄記, vol. 18, Taishō Tripiṭaka, vol. 35, p. 440.].

Following the parinirvāṇa of Master Fazang, his foremost disciple, Master Huiyuan, continued to expound upon Master Fazang’s teachings, particularly the doctrine of the dharmadhātu. However, in certain respects, Master Huiyuan’s interpretations diverged from the original intent of his teacher, thereby obscuring the true purport of Huayan thought concerning the dharmadhātu and rendering its ultimate meaning difficult to grasp.

In order to uphold the orthodox Huayan doctrines as expounded by Master Fazang and to safeguard the authentic transmission of the school’s thought, Master Chengguan refuted Master Huiyuan’s interpretations. In Commentary on the Elaboration of the Avataṃsaka Sūtra with Subcommentary, Master Chengguan writes the following: “As for the author of the 《KanDing Ji》, though he inherited the lineage of our tradition and had entered the gate of the late Master Fazang, he failed to discern the lost path of the straying sheep. Though he had passed through the abode of a virtuous friend, he remained ignorant of the jewel hidden within the robe.” (而《刊定記》主, 師承在茲, 雖入先生之門, 不曉亡羊之路; 徒過善友之捨, 猶迷衣內之珠) [Master Chengguan 澄觀大師, Commentary on the Elaboration of the Avataṃsaka Sūtra with Subcommentary 大方廣佛華嚴經隨疏演義鈔, vol. 3, Taishō Tripiṭaka 大正藏, vol. 36, p. 17.].

Here, Master Chengguan clearly indicates that Master Huiyuan failed to comprehend the profound intent of Master Fazang and thus offered misguided interpretations, which posed a threat to the faithful transmission of Huayan doctrine.

Therefore, in order to render the thought of the Huayan school more accessible and intelligible, Master Chengguan, building upon Master Fazang’s interpretation of the doctrine of the dharmadhātu, states the following in Commentary on the Chapter of the Aspiration Verses of Samantabhadra Bodhisattva in the Avataṃsaka Sūtra:

“Hence, the dharmadhātu may be provisionally divided into three types: (1) the Dharmadhātu of Phenomena, (2) the Dharmadhātu of Principle, (3) the Dharmadhātu of Non-Obstruction. The Non-Obstruction, in turn, is of two kinds, thus yielding a fourfold classification of the dharmadhātu: namely, the Dharmadhātu of Non-Obstruction of Principle and Phenomena, and the Dharmadhātu of Non-Obstruction of Phenomena and Phenomena. The fivefold schema of the dharmadhātu set forth by earlier masters does not depart from this essential framework.” (故於法界略分三種：故於法界，略分三種：一、事法界，二、理法界，三、無障礙法界。無（障）礙有二，則分四種法界，謂事理無礙法界、事事無礙法界。古德立五種法界，亦不出此)

[Master Chengguan, Commentary on the Chapter of the Aspiration Verses of Samantabhadra Bodhisattva in the Avataṃsaka Sūtra 华严经普贤行愿品疏, vol. 1, 1996, p. 32.]

Through this exposition, Master Chengguan establishes the complete doctrinal system of the four dharmadhatus.

As Oh (1976, pp. 5–6) observes, “The dharmadhātu doctrine can be said to have been, by and large, founded by Tu-shun, formulated by Chih-yen, systematized by Fa-tsang, and elucidated by Cheng-kuan and Tsung-mi.”4

Within this doctrinal development, the one true dharmadhātu serves as the fundamental principle underlying the four dharmadhātus, and this notion was advanced by the esteemed lay scholar Li Tongxuan. His thought introduced a radical non-dual understanding that profoundly shaped the Huayan worldview.

As noted by Van Norden and Jones (2019), “Li’s central contribution to Huayan tradition is his teaching of the one true dharma realm (Ch. yi zhen fajie). According to this teaching, all places and objects in the world are true just as they are. There is no real ontological separation between the sacred and the secular, enlightenment and ignorance, or the Buddha and sentient beings”.

Thus, the teaching of the one true dharmadhātu not only grounds the conceptual structure of the four dharmadhātus but also offers a profound framework for understanding the unity of mind and reality. It illuminates the seamless correspondence between ontological principle and phenomenological consciousness, affirming that the awakened mind and the totality of the dharmadhātu are inherently non-dual.

Regarding the doctrinal content of the four dharmadhātus and the characterization of each respective dharmadhātu, the section titled “The Twenty-Seventh: The Name and Essence of the Dharmadhātus (第二十七法界名體)” in the Brief Commentary on the Avataṃsaka Sūtra (大華嚴經略策) provides the following discussion:

“The Twenty-Seventh: The Name and Nature of the Dharmadhātu. Question: What is the meaning of ‘Dharmadhātu’? What does Dharmadhātu signify? Answer: ‘Dharma’ refers to that which upholds and maintains order, while ‘dhātu’has two meanings. First, in terms of phenomena, ‘dhātu’ signifies differentiation, as phenomena are distinguished according to their characteristics. Second, in terms of nature, ‘dhātu’refers to the principle of the Dharmadhātu, which is the unchanging essence of all dharmas. These two aspects interweave to form the ‘Dharmadhātu of Non-Obstruction between Principle and Phenomena’, where phenomena are grounded in principle, and principle is manifested through phenomena. When the two mutually negate each other, both phenomena and principle vanish; when they mutually affirm each other, phenomena and principle eternally coexist. The fourth is the ‘Dharmadhātu of Non-Obstruction among Phenomena’, which arises because principle harmonizes and integrates all phenomena.”5

In this context, the meaning of the dharmadhātu is employed to elucidate the interrelated significance of the four dharmadhātus. Central to the concept of the four dharmadhātus is the philosophical relationship between phenomena (Shi, 事) and principle (Li, 理)6—that is, between the phenomenal manifestations and ultimate truth.

The mature formulation of Master Chengguan’s doctrine of the four dharmadhātus is found in his major work, The Mysterious Mirror of the Avataṃsaka Dharmadhātu (華嚴法界玄鏡). In this text, Master Chengguan offers a systematic exposition of the fully developed theory of the four dharmadhātus, aligning it with Master Dushun’s “Three Contemplations” and explicitly correlating these contemplative methods with the fourfold structure of the dharmadhātu. Particular emphasis is placed on the dharmadhātu of non-obstruction of phenomena and phenomena, as this is the highest realization of this framework.

In The Mysterious Mirror of the Avataṃsaka Dharmadhātu, the following is stated:

“The term ‘Dharmadhātu’ represents the profound essence of the entire Avataṃsaka Sūtra, which takes the inconceivable Dharmadhātu of dependent arising as its fundamental principle. The characteristics of the Dharmadhātu can be summarized into three aspects, yet they comprehensively encompass four types: (1) the Dharmadhātu of Phenomena, (2) the Dharmadhātu of Principle, (3) the Dharmadhātu of Non-Obstruction of Principle and Phenomena, and (4) the Dharmadhātu of Non-Obstruction of Phenomena and Phenomena.”

[Master Chengguan. The Mysterious Mirror of the Avataṃsaka Dharmadhātu, 卷上, p. 672.]

This section systematically introduces the four types of dharmadhātu and states explicitly that the notion of “four dharmadhātus” is intended to capture the ultimate purport of the Avataṃsaka Sūtra. Only after one comprehends the philosophical implications of each dharmadhātu and the interrelations among them can one proceed, from the highest perspective, to harmonize the four dharmadhātus. This harmonization is integrated with Master Dushun’s Three Contemplative Doctrines—namely, the Contemplation of True Emptiness, the Contemplation of Non-Obstruction Between Principle and Phenomena, and the Contemplation of Omnipresent Inclusiveness—to highlight and elucidate the consummate realization of the dharmadhātu of non-obstruction of phenomena and phenomena, which represents the supreme fulfillment of the Huayan teaching.

The four types of dharmadhātu are as follows: the dharmadhātu of phenomena; the dharmadhātu of principle; the dharmadhātu of non-obstruction of phenomena and principle; The dharmadhātu of non-obstruction of phenomena and phenomena.

According to Master Chengguan, in terms of the dharmadhātu of phenomena, “It signifies differentiation, as it distinguishes according to the characteristics of phenomena” (即分義, 隨事分別故). [Brief Commentary on the Avataṃsaka Sūtra, vol. 1, Taishō Tripiṭaka, vol. 36, p. 707.].

In brief, everything that can be perceived, seen, heard, or sensed in this Saha world—all conditioned dharmas and limitless phenomena—are, in relation to the ultimate truth, physical manifestations and appearances within the realm of sensory experience. In reality, regardless of which dharmadhātu or world one refers to, all differentiated forms and physical functions that manifest through conditions belong to the dharmadhātu of phenomena. Generally speaking, this is a realm of “wondrous existence” (miaoyou妙有)—transient, conditionally arisen illusions that are ultimately empty and insubstantial.

The dharmadhātu of principle, on the other hand, is described as follows: “in terms of its essential nature, it refers to the immutable essence of all dharmas” (性義為諸法性不變易故). “Principle” stands in contrast to “phenomena”: “Differentiation pertains to phenomena; absence of differentiation pertains to principle” (分即是事, 無分是理). [Commentary on the Elaboration of the Avataṃsaka Sūtra with Subcommentary, vol. 24, Taishō Tripiṭaka 大正藏, vol. 36, p. 181.].

The universal truth of the cosmos—unchanging and indivisible—is none other than the tathatā (true suchness) that defines the dharmadhātu of principle. It corresponds to the notion of “true emptiness” (zhenkong 真空), which is not in opposition to “wondrous existence” but coexists with it in an integrated and non-dual fashion. As Chang (1971, p. 143) notes, “Of all the different Lis, the Hwa Yen philosophers seem to have in mind primarily the ultimate Li—namely, tathatā (suchness or thatness), either interpreted as the universal one mind (Yi Xin) or as emptiness (K’ung)”.

Therefore, the dharmadhātu of principle emerges as an insight developed once an individual attains a certain level of understanding regarding the dharmadhātu of phenomena. It is a gradual realization of the foundational ground upon which all phenomena arise, wherein one comes to perceive that, despite the apparent differences among worldly things, their essential nature is fundamentally equal, undifferentiated, and rooted in one principle. This realization reveals that the differences among phenomena are only apparent, while their underlying reality is the same.

This process mirrors a common human experience: one initially regards worldly phenomena as genuinely existent and substantial, but through transformative encounters or contemplative insight, one begins to recognize that such perceived “substantiality” is not eternal. This awareness initiates a deeper inquiry into the eternal and ultimate truth—leading from a differentiated understanding based on “phenomena” toward a more profound grasp of “principle”. It is precisely this transformative recognition that marks the transition from the dharmadhātu of phenomena to the dharmadhātu of principle, at least within the scope of these first two dharmadhātus.

Upon further contemplation and insight into the nature of truth (li) and phenomenal appearances (shi), one comes to recognize that physical phenomena—though marked by form, obstruction, and visible characteristics—possess no substantial essence whatsoever. In contrast, what truly exists as the ultimate reality is the dharmadhātu of principle, which corresponds to the original mind and constitutes the fundamental ontological ground. Consequently, the inherent qualities of the dharmadhātu of phenomena and the dharmadhātu of principle naturally entail mutual influence and integration. Through phenomena, one gradually realizes principle, and principle is constantly made manifest through phenomena.

This dynamic interplay is clearly illustrated by Master Chengguan in his Commentary on the Elaboration of the Avataṃsaka Sūtra with Subcommentary, where he employs the metaphor of “movement and stillness”: “Movement pertains to phenomena; stillness pertains to principle. Movement and stillness arise from a single source, thus revealing the dharmadhātu of non-obstruction between phenomena and principle.” (動即是事，靜即是理。動靜一源，即事理無礙法界也) [Commentary on the Elaboration of the Avataṃsaka Sūtra with Subcommentary, vol. 1, Taishō Tripiṭaka, vol. 36, p. 2.].

All phenomenal appearances are impermanent, while the truth of reality is immutable and tranquil. Yet movement and stillness arise from the same source—both are expressions of the one mind. There is stillness within movement and movement within stillness. This idea is concisely summarized by Chang (1971, p. 143): “In short, ‘Li’ is conceived of here as the all-inclusive and many-sided principle, fundamental for all existence, yet indeterminable in its contents. The dharmadhātu of Shi and the dharmadhātu of Li cannot be regarded as two separated realms. They are inseparable and interdependent, forming a unified whole. They are listed here as two separate realms only for the sake of illustration”.

As this relationship unfolds, it begins to reveal the Huayan doctrine of perfect interfusion. The mutual non-obstruction between principle and phenomena—the dharmadhātu of non-obstruction of phenomena and principle—marks a pivotal point of philosophical integration. Master Chengguan elaborates with the following: “Phenomena are grounded in principle, and principle is revealed through phenomena. When the two negate each other, both phenomena and principle vanish; when they mutually affirm each other, phenomena and principle eternally abide.” (事攬理成，理由事顯。二互相奪, 即事理兩亡, 若互相成，則常事常理) [Brief Commentary on the Avataṃsaka Sūtra, vol. 1, Taishō Tripiṭaka, vol. 36, p. 707.].

Phenomena exist only by virtue of borrowing the substance of truth; they do not exist independently. Without the causal condition of principle, phenomena would not come into being. Thus, precisely because phenomena borrow from principle for their existence, and because principle is revealed and functions through phenomena, one cannot assert that all is simply empty. If principle and phenomena existed in isolation without mutual interfusion, phenomena would be nonexistent, and principle would have no efficacy. Yet when the two inter-affirm, phenomena carry the Way, and principle is entirely luminous.

In this sense, principle and phenomena are mutually non-obstructive and arise dependently, without impeding each other. Whether one speaks of differentiated, illusory appearances or undifferentiated, truly empty reality, both are mutually interpenetrating and inseparable. The conventional names “principle” and “phenomena” merely denote the dynamic and unimpeded functioning of truth; they are carriers of the dharma. Should the two be separated, phenomena cease to exist; if they obstruct each other, truth loses its efficacy. Hence, the dharmadhātu of non-obstruction of phenomena and principle arises.

Hamar (2014, pp. 145–65) also notes that “Chengguan relates the dharmadhātu to phenomena, because they are divided, as well as to principle, which he equates with the Buddha-nature or the absolute nature. As this one term includes both meanings, the two meanings intermingle, which is the dharmadhātu of phenomena and principle”.

Master Chengguan interprets the four dharmadhātus through the varied meanings of dhātu: first, as division or differentiation; and second, as intrinsic nature.

In truth, the four dharmadhātus evolved from the foundational concept of the dependent arising of the dharmadhātu and unfolded through the framework of the one true dharmadhātu. Therefore, to grasp the process through which the dharmadhātu diversifies, one must intuitively realize the highest perspective—only then can the relationship and true meaning of the dharmadhātu and the one true dharmadhātu be fully understood.

However, even though the dharmadhātu of non-obstruction of phenomena and principle achieves the profound mutual integration of principle and phenomena, it still retains their conventional names and thus remains within the realm of dualistic cognition. To speak of “phenomena” implies “principle,” and to speak of “principle” presupposes “phenomena”. Although the two influence each other, they have not yet reached the fundamental and ultimate level, nor does this stage embody the total and un-obstructed realization of one mind emphasized in the Huayan tradition. As such, it cannot fully elucidate the one true dharmadhātu without further development.

From another perspective, this also implies that whether one speaks of principle and phenomena, or of all four dharmadhātus, their ultimate ground is none other than the singular, true dharmadhātu—the one true dharmadhātu. It alone can encompass and unify any of the dharmadhātus. Thus, the framework of the four dharmadhātus serves to guide sentient beings from delusion to awakening. In brief, as one gains clarity of principle, one realizes the original purity of phenomena. The essence of principle becomes fully manifest and active within the realm of phenomena, leading to the non-duality of principle and phenomena, to the total clarity and purity of mind, and ultimately to awakening and liberation.

At this level, there remains no conceptual distinction between “principle” and “phenomena.” Even the phrase unity of principle and phenomena (事理不二) is merely an expedient expression. True insight transcends speech; only through direct realization beyond language and conceptual constructs can one comprehend the ultimate, wondrous truth.

The Buddhadharma is the dharma of non-duality—one, not two. One is two; two is one (佛法是不二之法，是一不是二，一就是二、二就是一). The nature remains unchanging; mind and world are of one suchness. This contains the very key to authentic spiritual cultivation and realization.

The existence of principle (li) serves as the basis for the mutual communication and integration among ultimate realities. In a philosophical sense, principle constitutes the very foundation of the dharmadhātu of non-obstruction of phenomena and phenomena; it is through principle that phenomena become harmonized. As a result, the myriad forms that arise as differentiated phenomena are able to interpenetrate without obstruction. Principle itself is characterized by a singular, indivisible essence of non-duality. Therefore, this necessitates a return to the dharmadhātu of non-obstruction of phenomena and phenomena—the realization that Buddha-nature is inherently complete and one’s own nature is originally endowed.

Hamar (2014, pp. 145–65) affirms that “Chengguan also emphasizes that these two aspects, phenomenal existence and absolute nature, cannot be separated: they cannot exist without each other. Finally, Chengguan affirms that the dharmadhātu of non-obstruction of phenomena can be established because all phenomena are endowed with the absolute nature.”

As a pair of philosophical categories, phenomena and principle do not exist in opposition. In fact, their relationship mirrors that between the one true dharmadhātu and its manifold expressions as the evolving dharmadhātu. This is a relationship of “true emptiness and wondrous existence, and wondrous existence and true emptiness”—demonstrating both the ultimate reality of all dharmas and the holistic unity of the four dharmadhātus. This further reveals that Buddha-nature is an undivided whole—neither increasing nor decreasing, neither arising nor ceasing—rather than a composite of four discrete dharmadhātus.

Through the interplay of phenomena and principle, and the conceptual relationship between the dharmadhātu of non-obstruction of phenomena and principle and the dharmadhātu of non-obstruction of phenomena and phenomena, one can understand that suchness and the myriad dharmas are not in conflict, but are more akin to the relationship between the mind and its experiential realm. Therefore, from the Huayan perspective, the relationship between phenomena and principle serves as a demonstration of the ultimate and perfectly integrated wisdom of the Buddha.

Indeed, the true nature of this relationship can only be fully elucidated at the level of the dharmadhātu of non-obstruction of phenomena and phenomena. That is, whether one speaks of phenomena and principle, or the entire system of the four dharmadhātus, from the ultimate standpoint, all are reducible to the one and only true dharmadhātu—the one true dharmadhātu—which is, in essence, the perfectly integrated wisdom of Buddhahood embodied in the dharmadhātu of non-obstruction of phenomena and phenomena.

Master Chengguan’s interpretation of the interplay between principle and phenomena was deeply influenced by Master Fazang. By incorporating this with Master Fazang’s teachings, one may gain a more comprehensive understanding of the Li–Shi (principle–phenomena) relationship. Master Fazang once wrote that “Though phenomena appear vividly, they are eternally devoid of intrinsic existence; thus, function is none other than substance, like the gathering of all rivers into the ocean. Though principle is of one taste, it eternally adapts to conditions; thus, substance is none other than function, like the ocean revealing itself through the myriad streams.” (事雖宛然，恆無所有，是故用即體供，如會百川以歸於海。理雖一味，恆自隨緣，是故體即用也，如舉大海以明百川) [The Hundred Gates to the Ocean of Meaning in the Avataṃsaka Sūtra: The Ninth Gate on the Opening and Closing of Substance and Function, Taishō Tripiṭaka, vol. 45, p. 635.].

This passage expresses the epistemological view that phenomena and principle relate as function and substance—mutually inclusive and inseparable. Master Fazang further proposed a “fivefold relationship” between principle and phenomena: mutual pervasion (相遍), mutual formation (相成), mutual negation (相奪), mutual identity (相即), and mutual non-identity (相非). In summary, this means that the original mind, as principle, both generates and encompasses all phenomenal appearances. At the ultimate level, phenomena are principle and principle is phenomena. The dharmadhātu of principle, the dharmadhātu of phenomena, the dharmadhātu of non-obstruction of phenomena and principle, the dharmadhātu of non-obstruction of phenomena and phenomena, and even the one true dharmadhātu, are ultimately one reality. To understand one is to understand the other; to realize one is to realize both.

In conclusion, both the dharmadhātu of principle and the dharmadhātu of phenomena are expressions of the myriad dharmas. In the state of the dharmadhātu of non-obstruction of phenomena and principle, principle becomes fully transparent and integrated—wherein all dharmas are expressions of the true mind. Phenomena, in turn, become accessible and utilizable according to conditions, with no discord among the countless appearances of the world. At this stage, neither principle nor phenomena dominate; instead, they freely function in perfect harmony.

The dharmadhātu of non-obstruction of phenomena and phenomena reflects this original nature—it is how self-nature truly is. Ultimately, the four dharmadhātus are but one. Linguistic and conceptual distinctions serve only as expedient means.

As Master Chengguan declares in The Mysterious Mirror of the Avataṃsaka Dharmadhātu, the four dharmadhātus express the ultimate intent of the Avataṃsaka Sūtra. As one of the core teachings of the Huayan school, the doctrine of the four dharmadhātus embodies the ideal of harmonious interpenetration. In any given dharmadhātu, the universal principle is fully integrated, and within the infinite appearances that pervade the entire dharmadhātu, not a single phenomenon fails to be infused with principle. As expressed in the Avataṃsaka Sūtra, “In every mote of dust within the Lotus Treasury World, the entire Dharmadhātu is revealed.” (華藏世界所有塵, 一一塵中見法界) [Translated by Śikṣānanda實叉難陀, Avataṃsaka Sūtra 大方廣佛華嚴經， Chapter on the Huazang World 華藏世界品第五, Taishō Tripiṭaka 大正藏, vol. 10, p. 39.].

The doctrine of the four dharmadhātus originates from the one true dharmadhātu. As the spontaneously manifesting source of original awakening, the one true dharmadhātu reveals the wondrous existence of the “four” dharmadhātus. Through an in-depth understanding of the four dharmadhātus, culminating in the realization of the inherent nature of the dharmadhātu of non-obstruction of phenomena and phenomena, one gains insight into the full scope of reality—integrating the various dimensions of life, including principle and phenomena and nature and form. This manifests the Huayan school’s unique quality of perfect interpenetration.

In truth, the four dharmadhātus—the dharmadhātu of principle, the dharmadhātu of phenomena, the dharmadhātu of non-obstruction of phenomena and principle, and the dharmadhātu of non-obstruction of phenomena and phenomena—are one, not four. They cannot be regarded as four discrete categories with separate meanings. The one true dharmadhātu and the four dharmadhātus are not two distinct entities but a single, indivisible whole.

As Master Chengguan states, “The Dharmadhātu of Non-Obstruction among Phenomena is so called because principle harmonizes and integrates all phenomena.” (事事無礙法界，謂由以理融彼事故)

[Brief Commentary on the Avataṃsaka Sūtra, vol. 1, Taishō Tripiṭaka, vol. 36, p. 707.]

Every phenomenon reflects the real functioning of principle; each phenomenon carries the Way, and principle is present in all things. Hence, the transition from the dharmadhātu of non-obstruction of phenomena and principle leads to fundamental wisdom—namely, the realization of the dharmadhātu of non-obstruction of phenomena and phenomena. Only upon entering this dharmadhātu does one fully comprehend true interpenetration without obstruction.

Within the dharmadhātu of non-obstruction of phenomena and phenomena, there is no conceptual distinction or provisional naming of principle and phenomena. One speaks directly of the one true dharmadhātu, which is none other than the one mind tathāgatagarbha (一心如來藏)—our originally pure nature of bodhi (awakening). Though the myriad conditioned dharmas appear differentiated on the surface, from the perspective of the one mind, they are essentially one in nature—non-dual, where the one contains the many and the many contain the one; the great is within the small, and the small is within the great; one is all, and all is one. This interrelation is infinite and boundless.

Thus, it becomes evident that the four dharmadhātus are, in terms of their essence, non-differentiated. All arise from the one mind, are comprehended through the one mind, and manifest complete harmony and mutual interpenetration.

This very insight is echoed later by the Sixth Patriarch of the Chan tradition 禪宗六祖, Master Huineng (惠能大師, 638–713), who proclaims “Who would have thought that the self-nature can give rise to all phenomena.” (何期自性, 能生萬法) [Zongbao, The Platform Sūtra of the Sixth Patriarch, Chapter 1, p. 349.].

That is, the self-nature gives rise to all dharmas while remaining unborn and undying. All dharmas are neither increased nor decreased, but arise from self-nature.

Textually, this shows that “self-nature” encompasses all dharmas, and all dharmas are expressions of self-nature. One may thus pose the philosophical question: How does self-nature give rise to all dharmas? Why are all dharmas nothing other than self-nature? If there were no original nature, whence would the myriad dharmas arise? From what would they conditionally originate? This is a supplementary explanation of the inner logic between the one true dharmadhātu and the dharmadhātu.

In my own work, Study on the Ontology of ‘True Mind’ in Huayan Buddhism, I discuss this issue as follows: “In The Records of the Source-Mirror (宗镜录), deluded thoughts of sentient beings are compared to waves on water, while the calm water symbolizes the empty mind free from delusion. Whether turbulent or still, the nature of water remains unchanged”. “Whether one speaks of water and ice, snow and water, or water and waves, the relationship among them illustrates that every wave embodies the nature of water—there is no external form Dharma apart from mind Dharma. The differing states of water, ice, snow, or waves correspond to various dharmadhātus. Each dharmadhātu manifests its characteristic form, but as previously explained, regardless of how many dharmadhātus there may be, their essence remains unchanged. Furthermore, the dharmadhātu, as the field of diverse appearances, must rely upon its ontological ground in order to manifest. From a fundamental perspective, all are one and indivisible. The distinctions that appear among different dharmadhātus merely reflect the mind’s projection of varied phenomenal realms.” (Wang 2022, pp. 281–96).

The relationship between the one true dharmadhātu and the four dharmadhātus is akin to that between water and waves, essence and function, or substance and manifestation. It embodies the dynamic of “true emptiness as wondrous existence” and “wondrous existence as true emptiness”. As such, the four dharmadhātus also contain an epistemological paradigm—one that is not only conceptual but also realized through direct meditative experience.

We may thus understand the statement, “Who would have thought that the self-nature is originally pure” [Zongbao, the Platform Sūtra of the Sixth Patriarch, Chapter 1, p. 349], to affirm that the evolution from the one true dharmadhātu into the four dharmadhātus, and ultimately to the realization of the dharmadhātu of non-obstruction of phenomena and phenomena, remains within the experiential scope of the one true dharmadhātu. There is, in essence, no difference between mind, Buddha, and sentient beings.

As Hamar (2014, pp. 145–65) explains, “If a person can realize the real meaning of the dharmadhātu, he or she can return to the one mind.”

Hence, we must first clearly understand the mode of awakening articulated in the four dharmadhātus. An ancient verse reads “The hues of spring know no hierarchy, yet the branches of flowers vary in length.” (春色無高下，華枝有短長) [Fu’an, the Systematic Outline of the Avataṃsaka Sūtra, in Śikṣānanda’s translation of the Avataṃsaka Sūtra, 1986, p. 6.].

The line “The hues of spring know no hierarchy” expresses that there is no essential difference among mind, Buddha, and sentient beings—each individual inherently possesses a mind and nature that is identical to Buddha-nature. As the Chan tradition puts it, “The Buddha-Dharma is neither sudden nor gradual” (法無頓漸). Yet in terms of the progressive unfolding of discernment (見地), the line “the branches of flowers vary in length” points to the differing karmic conditions and obscurations that cause individuals to realize awakening at different moments. This is referred to as “delusion and enlightenment unfold at varying speeds” (迷悟有遲疾), which accounts for why one might perceive the dharmic functioning of the dharmadhātu of phenomena, the dharmadhātu of principle, or the dharmadhātu of non-obstruction of phenomena and principle.

Therefore, the awakening of consciousness in the context of the four dharmadhātus is not necessarily a step-by-step, progressive path. Rather, it is a case of sudden awakening (dunwu, 頓悟), whereby one directly enters the dharmadhātu of non-obstruction of phenomena and phenomena. One may also enter this dharmadhātu from any of the four, reaching the final realization in a free and un-obstructed manner—perfectly integrated and without hindrance.

However, even upon attaining the dharmadhātu of non-obstruction of phenomena and phenomena, one must return to the one true dharmadhātu, for the dharmadhātu of non-obstruction of phenomena and phenomena is, in its essence, none other than the innate bodhi-nature. Therefore, to clearly recognize the essence of awakening is to realize that self-nature is Buddha, as expressed in the line “Apart from the nature, there is no other Buddha” (離性無別佛) [Zongbao, the Platform Sūtra of the Sixth Patriarch, Chapter 2, p. 350].

All phenomena arise from self-nature. As self-nature pervades the entire Dharma Realm and fills infinite space (盡虛空遍法界), all manifestations are expressions of this one nature. Their mutual interpenetration and complete harmony reveal the truth of non-discrimination and unhindered realization.

3. The Unimpeded and Integrated Path of Awakening in the Doctrine of the Four Dharmadhātus

Through a deep understanding of the doctrinal content of the four dharmadhātus and the epistemological significance of “mind and consciousness” (xinshi, 心識), it becomes clear that the four dharmadhātus are not merely theoretical constructs. Rather, they constitute a profound and direct realm of realization, providing sentient beings with a clear and accessible path to awakening. Thus, the Huayan school’s vision of awakening through the four dharmadhātus is characterized by total integration and unimpeded progression.

The path of realization is provisionally expressed through four phases—namely, the phase of the dharmadhātu of phenomena, the phase of the dharmadhātu of principle, the phase of the dharmadhātu of non-obstruction of phenomena and principle, and the phase of the dharmadhātu of non-obstruction of phenomena and phenomena. As has been demonstrated in the foregoing discussions of the doctrinal meaning of the four dharmadhātus, this process of awakening aligns seamlessly with the framework of faith–understanding–practice–realization (xinjiexingzheng) found in the Avataṃsaka Sūtra, and with the fourfold method of opening–revealing–awakening–entering (kaishiwuru) presented in the Lotus Sūtra. Both are expressions of the same wondrous dharma.

To begin with, let us examine the meaning of faith, understanding, practice, and realization. This framework was systematized by the eminent Huayan patriarch Master Chengguan in his Commentary on the Chapter of the Aspiration Verses of Samantabhadra Bodhisattva in the Avataṃsaka Sūtra 華嚴經普賢行願品疏, where he explains:

“The first part, corresponding to the first assembly, is called ‘The Section on Presenting the Fruit to Inspire Joy and Generate Faith’. It presents the vast ocean of Buddha-lands, the boundless clouds of the Tathāgata’s body, and the all-pervading nature of the Lotus Treasury World, inspiring beings to rejoice and realize their inherent connection, thereby generating faith. The second part, spanning from the second to the seventh assembly, is named ‘The Section on Cultivating Causes to Accord with the Fruit and Generate Understanding’. It teaches the cultivation of the perfect causes of the five stages, aligning with the ultimate fruit of perfect enlightenment, enabling beings to correctly comprehend the relationship between cause and effect. The third part, corresponding to the eighth assembly, is called ‘The Section on Relying on the Dharma to Advance in Practice and Accomplish Action.’ It relies on the teachings of the six stages, encouraging beings to progress in their practice and fully embody the Dharma, as understanding is realized through action. The fourth part, corresponding to the ninth assembly, is named ‘The Section on Relying on Sages to Attain Realization and Accomplish Virtue.’ It relies on the causal and resultant stages of Buddhas and Bodhisattvas, guiding beings to enter the dharmadhātu and embody its virtues, as practice inevitably leads to realization and fruition. Although the Buddha’s teachings are vast, they do not go beyond these four: faith, understanding, practice, and realization. Within these four sections, each contains elements of the others, but each is named according to its predominant emphasis.”7

Master Chengguan emphasizes that the first step is faith—a deep confidence that arises from within. This faith is awakened through “presenting the fruit to inspire joy”, which introduces sentient beings to the vast and sublime truths of karmic causality, impermanence, suffering, and emptiness. This cultivates a desire for liberation. Furthermore, because the dharma-body of the Tathāgata pervades all space and the entire Dharma Realm, sentient beings come to realize that they all have a share in the Buddha’s supreme wisdom. This generates joyful confidence in the Dharma and stable faith in the Three Jewels after the Buddha’s entry into parinirvāṇa. This is the stage of faith.

Once faith is established, one proceeds to understanding—the inner realization of the profound truths of the Dharma. Through “cultivating causes to accord with the fruit”, one gains correct insight into the Dharma’s subtleties and realizes the luminous, innate wisdom within. This leads to practice, the next stage. As expressed in “relying on the Dharma to advance in practice”, practice is grounded in the Dharma and proceeds under its guidance. Every thought and action becomes an expression of the path, and one’s practice becomes continuous and unimpeded.

Eventually, this culminates in realization—awakening to the true nature of reality and entering the Dharma Realm.

According to Venerable Jiequan 界詮法師, this fourfold framework corresponds to another schema of Buddhist cultivation—teachings, principles, practice, and fruits (教理行果):

“In the Dharma of the Buddha, there are four aspects: teachings, principles, practice, and fruits. The teachings refer to the words, phrases, texts, and sounds spoken by the Buddha, as well as the various methods he employed to dispel ignorance and afflictions—namely, the Tripiṭaka and the twelve divisions of scripture. The principles refer to the truths expounded by the teachings, which reveal the ultimate nature of the universe and life. The practice refers to the cultivation of precepts, meditation, and wisdom, based on these principles. The fruits refer to the sacred attainments realized through complete and perfected practice. The entire body of the Tathāgata’s teachings does not go beyond these four. Through teachings, principles are revealed; based on principles, practice arises; through practice, the fruits are attained. Nothing lies outside these four. The schema of faith, understanding, practice, and realization directly corresponds to these four aspects. Faith means trusting the Buddha’s teachings; understanding means comprehending their principles; practice means acting upon them; and realization means attaining the fruits of the path.”8

This clarification allows the structure of faith, understanding, practice, and realization to be seen in a more complete light.

In fact, while Master Chengguan emphasizes this framework, he also values the teaching of “Opening, Revealing, Awakening, and Entering”, as found in The Lotus Sūtra (妙法蓮華經). This doctrine appears in Chapter 2, Expedient Means (方便品第二):

“All Buddhas, the World-Honored Ones, appear in the world for one great cause alone. Śāriputra! What is this one great cause for which all Buddhas, the World-Honored Ones, appear in the world? All Buddhas, the World-Honored Ones, appear in the world so that living beings may open the wisdom and vision of the Buddha, and thereby become pure. They appear in the world to reveal the wisdom and vision of the Buddha to living beings. They appear in the world so that living beings may awaken to the wisdom and vision of the Buddha. They appear in the world so that living beings may enter the path of the wisdom and vision of the Buddha. Śāriputra! This is the one great cause for which all Buddhas appear in the world.”

[Kumārajīva trans., The Lotus Sutra-Chapter Two: Expedient Means, p. 7.]

In both Huayan and Lotus traditions, the progression toward awakening is ultimately an expression of the same truth: that sentient beings possess the innate capacity for Buddhahood and can awaken through the unimpeded integration of understanding and practice. This is the profound and complete path of awakening embodied in the four dharmadhātus.

As the Sixth patriarch Huineng 六祖惠能大師 states:

“The Buddha is none other than awakening. This awakening is divided into four gates: opening the wisdom and vision of awakening, revealing the wisdom and vision of awakening, realizing the wisdom and vision of awakening, and entering the wisdom and vision of awakening. If one hears the opening and revealing, one can then realize and enter. This is the wisdom and vision of awakening, through which the true nature, originally present, manifests.”

[Zongbao, The Platform Sūtra of the Sixth Patriarch—Chapter Seven: On Opportunity and Condition, p. 355.]

Sentient beings, through the Buddha’s presence in the world and through the supreme cause and condition of “the Wisdom and Vision of the Buddha,” are able to awaken. The four gates of opening, revealing, awakening, and entering constitute the “condition” (yuan, 缘) of this “great cause” (dashi yinyuan, 大事因缘), enabling beings to perceive the Buddha’s insight and access the deeper meaning of the scriptures.

Regarding the subtle meaning of opening–revealing–awakening–entering, the Tiantai patriarch Master Zhiyi (天台宗智者大師, 538–597) provides a detailed analysis in his Profound Meaning of the Lotus Sūtra (妙法蓮華經文句):

“To open refers to the Ten Abodes (十住). Initially, it means to break through ignorance and open the treasury of the Tathāgata, thereby revealing the principle of ultimate reality. At the beginning stage, one can fully believe, receive, and subdue afflictions, but until delusion is severed, it is not yet called ‘opening.’ Through internal contemplation and external assistance from the Dharma rain, one breaks both general and specific delusions, thereby illuminating the true nature of cultivation. Wisdom and vision shine forth like the rising sun dispelling darkness, enabling clarity of perception—thus, it is called ‘opening.’ To reveal means that when delusions are removed, the essence of insight manifests. This essence, complete with all virtues, clearly displays the full range of qualities within the dharmadhātu. Hence, it is called ‘revealing.’ To awaken means that with hindrances eliminated and the essence revealed, the path of the dharmadhātu becomes luminous. Principle and phenomena interpenetrate without duality. As Mahāyāna masters say, ‘There is the wisdom of suchness and the wisdom of discernment.’ Since these are non-dual, it is called ‘awakening.’ To enter means that once principle and phenomena are harmonized, one attains unimpeded freedom—naturally flowing, effortlessly progressing from beginning to end, and entering the ocean of omniscient wisdom (Sarvajñā). As Mahāyāna masters put it, ‘Thusness and discernment are freely penetrated.’ The wisdom of discernment sustains all virtues; the wisdom of suchness eliminates all delusions. Thus, the act of opening inherently includes revealing, awakening, and entering. These are not separate processes, but manifestations of the wisdom of suchness itself, free from any gradation or dualistic distinction.”9

Master Zhiyi emphasizes that opening initiates the process by breaking ignorance and unveiling the tathāgatagarbha; revealing occurs when the obstructing delusions are removed, allowing the true wisdom-nature to manifest; awakening arises from the interpenetration of phenomena and principle; and entering signifies the attainment of unimpeded realization within the boundless ocean of wisdom.

However, it must be noted that entering the Buddha’s wisdom and vision (ru fozhi jian 入佛知見) is not the end; one must also emerge from it. Awakening involves realizing one’s own original nature, seeing that it is not different from the Buddha-nature. Thus, to emerge from the Buddha’s wisdom has two implications.

First, it points to the active function of wisdom arising from self-nature—as Huineng says, “Who would have thought that the self-nature can give rise to all phenomena.”

This realization allows one to employ this awakened insight as freely functioning wisdom. Second, if one remains solely in the Buddha’s vision without emerging from it, one will speak, perceive, and act only according to “how the Buddha sees,” (佛見如何) “how the Buddha hears,” (佛聞如何) “how the Buddha knows,” (佛覺如何) etc., thereby remaining dependent rather than truly free. Since one’s own original nature is not different from the Buddha-nature, and all dharmas are manifestations of self-nature, it is only by emerging from the Buddha’s vision that one fully accesses and integrates the awakened functioning of the mind.

This is also the nature of realization in faith–understanding–practice–realization, and it is the realization inherent in the dharmadhātu of non-obstruction of phenomena and phenomena. At the root of awakening, what is perceived is none other than one’s own inherently complete and originally pure mind-nature—non-arising, non-ceasing, and requiring no external acquisition. This alone constitutes true awakening: the full realization of the “originally pure, radiant nature of self-nature”.

Thus, we can see that the subtle meaning of faith–understanding–practice–realization (xinjiexingzheng) and the wondrous method of opening–revealing–awakening–entering (kaishiwuru) are perfectly interconnected and harmonized with the Huayan doctrine of the four dharmadhātus:

Opening and faith correspond to recognizing the phenomenal appearances of the world—this is the realm of the dharmadhātu of phenomena. Revealing and understanding correspond to realizing the truth beyond appearances—this is the realm of the dharmadhātu of principle. Awakening and practice correspond to enacting the Dharma after realizing the truth, in which principle and phenomena are harmonized—this is the dharmadhātu of non-obstruction of phenomena and principle. Entering and realization correspond to the total integration and self-realization of Buddha-wisdom—this is the dharmadhātu of non-obstruction of phenomena and phenomena.

Therefore, the doctrine of the four dharmadhātus, the faith–understanding–practice–realization model of the Avataṃsaka Sūtra, and the opening–revealing–awakening–entering teaching of the Lotus Sūtra converge in a seamless and integrated path of awakening.

4. The Integration of the Real and the Ideal in the Doctrine of the Four Dharmadhātus

In Huayan Buddhism, principle and phenomena form one of its most crucial philosophical pairs and are core categories within the doctrine of the four dharmadhātus. Through the study of this doctrine, it becomes clear that principle and phenomena are not in opposition. At the most fundamental level, they are one and the same. To speak of them as separate is already to fall into dualism. Yet the Dharma is, by its nature, non-dual. The evolution of the four dharmadhātus from the one true dharmadhātu fundamentally expresses the doctrine that all dharmas arise from self-nature (zixing 自性). The one true dharmadhātu is none other than the true mind tathāgatagarbha, and thus, the four dharmadhātus are likewise expressions of non-duality and perfect interpenetration.

Accordingly, the concepts of principle and phenomena that structure the four dharmadhātus are themselves non-dual. The unity of principle and phenomena (shì-lǐ bù’èr, 事理不二) reveals the original non-distinction and seamless integration of reality. In Huayan thought, principle refers to the essential nature and ontological ground of things, while phenomena refer to material manifestations and functional activity. The idea of the unity of principle and phenomena thereby expresses the integration of the ideal (noumenon) and the real (phenomena). The essential nature (li) is pure Buddha-nature—one aspect of the “true emptiness” of the Buddha realm—while the manifest world of appearances (shi) constitutes the “wondrous existence” of the manifold world.

From the perspective of the four dharmadhātus, principle and phenomena are non-dual, true emptiness and wondrous existence are non-dual, and the expressions of the “one and the many,” or “one is all, and all is one,” are likewise non-dual. Therefore, the Buddha realm and the mundane world are, in essence, one and the same—perfectly integrated and without obstruction. Fang Litian observes that in Huayan Buddhist philosophy, the universe is an integrated whole, and all things are perfectly harmonious and un-obstructed.10

In fact, the one true dharmadhātu and the four dharmadhātus operate in this same mode. The “pure Buddha realm” (清淨佛界) and the “phenomenal world of appearances” (諸相世間) are not fundamentally different. Moreover, the one true dharmadhātu is precisely Buddha-nature. Although the four dharmadhātus encompass all dharmas, even the dharmadhātu of non-obstruction of phenomena and phenomena is none other than the inherent purity and awakened nature. Therefore, the self-nature of the one true dharmadhātu can contain all the myriad dharmas of the four dharmadhātus; self-nature gives rise to all dharmas, and all dharmas are expressions of self-nature. Mind and world are one, with no duality or separation, such that even invoking the term “non-dual” becomes unnecessary.

This resonates with the Vimalakīrti Sūtra, where in the Chapter on Entering the Gate of Non-Duality, Vimalakīrti responds to Mañjuśrī’s question—“What is the Bodhisattva’s entry into the gate of non-duality?” (何等是菩薩入不二法門)—with profound silence: “Vimalakīrti remained thunderously silent.” (維摩詰默然無言) [Kumārajīva trans. 鳩摩羅什譯, The Vimalakīrti Sūtra 維摩詰所說經, Taishō Tripiṭaka 大正藏, vol. 14, p. 551.].

Whether speaking of the diverse appearances of phenomena and the ontological basis of principle, or the differentiated appearances of the dharmadhātu in contrast to the pure tathāgatagarbha of the one true dharmadhātu, all of these are expressions of the relationship between affliction (kleśa) and awakening (bodhi). This is the relationship between true emptiness and wondrous existence, where form and emptiness interpenetrate. Though the dharmadhātu and phenomena reflect multiplicity and diversity, their ontological basis remains unchanged. They must rely upon this essence to appear, and thus cannot be understood apart from it.

This is precisely what is meant by the teaching “Afflictions are precisely bodhi.” (煩惱即菩提) [Zongbao, the Platform Sūtra of the Sixth Patriarch, Chapter 2, p. 350.].

As Jiang (2001, pp. 457–75) puts it:

“The natural soteriological conclusion that can be drawn in terms of the whole–part relation vis-à-vis the Huayan li/shi scheme is that… because of the infinite interpenetration of all, suffering and enlightenment likewise interpenetrate. This is tantamount to saying that suffering is no different from enlightenment and enlightenment is no different from suffering, echoing the well-known Madhyamaka motto: nirvana is samsara and samsara is nirvana.”

This means that one should not seek awakening apart from afflictions, for there is no essential difference between mind, Buddha, and sentient beings. The original nature of the mind is inherently pure and non-dual. As it is said, “In the moment of awakening, all beings are Buddha”. (一念悟時眾生是佛) [Zongbao, the Platform Sūtra of the Sixth Patriarch, Chapter 2, p. 351].

All phenomena in the universe are perfectly integrated and un-obstructed. The separation between Buddha realm and the mundane world is illusory. Obstruction arises only in one’s own mind. As Fang Dongmei eloquently states:

“All defiled and pure dharmas, without exception, rely on this mind. This mind possesses flawless merit and gives rise to infinite functions that benefit the world. It encompasses all supramundane Dharma. In the gate of suchness, it manifests absolute reason; in the gate of arising and ceasing, it manifests relative phenomena. These two are mutually interdependent. Without the absolute, there is no arising and ceasing; without arising and ceasing, there is no absolute. The two interpenetrate without obstruction, forming an infinitely radiant net like that of Indra. In this way, the entire mystery of the cosmos is revealed.”

(D. Fang 2012, p. 662).

Thus, the Huayan teaching of harmony through the four dharmadhātus enables a deeper understanding of the interrelation between the ideal and the real, the Buddha realm and the worldly realm. There is no need to artificially pursue tranquility, for “Afflictions are precisely bodhi.” [Zongbao, the Platform Sūtra of the Sixth Patriarch, Chapter 2].

The universe and all its dharmas interpenetrate freely and without obstruction. The only obstacles lie in one’s own deluded mind. If one can access the one mind, all becomes naturally harmonized. The world is inherently free from entanglement; it is only the deluded who disturb themselves.

5. Conclusions

Master Chengguan made a groundbreaking contribution to Huayan philosophy by formulating the doctrine of the four dharmadhātus. His efforts hold a position of great merit in the historical development of the Huayan school’s doctrinal system. The theoretical system he constructed rendered Huayan philosophy more intelligible, broadened the dissemination of Huayan philosophy, and made it more accessible to a wider audience. Consequently, posterity has come to regard Master Chengguan’s thought as the legitimate and orthodox continuation of the Huayan tradition.

The ultimate intent of the Huayan doctrine of the four dharmadhātus is one of genuine, non-deceptive realization. The practice paths and methods of cultivation it encompasses are likewise free from obstruction. The evolution of the four dharmadhātus from the one true dharmadhātu aims to guide sentient beings to realize that the path of awakening lies fundamentally within the mind—that the mind is the root of all things. Moreover, the progression from the dharmadhātu of phenomena to the dharmadhātu of non-obstruction of phenomena and phenomena represents not only a path of experiential realization but also a method of sudden awakening accessible directly through the mind.

The one true dharmadhātu evolves into the four dharmadhātus, yet all four dharmadhātus are none other than the one true dharmadhātu. Each of the four dharmadhātus—the dharmadhātu of principle, the dharmadhātu of phenomena, the dharmadhātu of non-obstruction of phenomena and principle, and the dharmadhātu of non-obstruction of phenomena and phenomena—mutually contains and harmonizes with the others. The dharmadhātu of principle encompasses and perfectly harmonizes the dharmadhātu of phenomena, the dharmadhātu of non-obstruction of phenomena and principle, and the dharmadhātu of non-obstruction of phenomena and phenomena. The dharmadhātu of phenomena encompasses and perfectly harmonizes the dharmadhātu of principle, the dharmadhātu of non-obstruction of phenomena and principle, and the dharmadhātu of non-obstruction of phenomena and phenomena. The dharmadhātu of non-obstruction of phenomena and principle encompasses and perfectly harmonizes the dharmadhātu of principle, the dharmadhātu of phenomena, and the dharmadhātu of non-obstruction of phenomena and phenomena. The dharmadhātu of non-obstruction of phenomena and phenomena encompasses and perfectly harmonizes the dharmadhātu of principle, the dharmadhātu of phenomena, and the dharmadhātu of non-obstruction of phenomena and principle. Any one dharmadhātu fully contains and integrates all the others; each is complete and perfect in and of itself. This is the meaning of “no diminution in the mundane, no increase in the sacred”—a core tenet of Huayan metaphysics.

Therefore, the ten faiths, ten abodes, ten practices, ten dedications, and ten grounds11 outlined in the Avataṃsaka Sūtra are all manifestations of this non-obstructed reality. They do not represent a sequential ascent or a step-by-step path to enlightenment, but rather reflect that each stage and moment is fully complete and self-sufficient—the ultimate expression of Huayan realization. All of these are presentations of ultimate reality—not progressive levels of attainment. There is no need to gradually climb stage by stage, for in every moment and every stage, the full truth is already perfectly present. This is the definitive teaching of Huayan.