On the Origin and Conceptual Development of ‘ Essence-Function ’ ( ti-yong )

‘Essence-function’(ti-yong體用), also called‘substance-function,’has been a constant topic of debate in monastic and academic communities in China. One group of scholars insists that the concept is derived from the Confucian tradition, while the other maintains that it originates with the Buddhist tradition. These opposing opinions are not merely the arguments of antiquity, but have persisted to our present time. This paper investigates the concept of‘essence-function,’focusing on its origin and conceptual development in the Buddhist and the Confucian traditions. This concept has become a basic framework of Chinese religions. Its root appears already in ancient Confucian and Daoist works such as the Xunzi and the Zhouyi cantong qi. It is, however, through the influence of Buddhism that‘essence’and‘function’became a paradigm used as an exegetical, hermeneutical and syncretic tool for interpreting Chinese philosophical works. This dual concept played a central role not only in the assimilation of Indian Buddhism in China during its earlier phases but also in the formation of Neo-Confucianism in medieval times. This paper shows that the paradigm constituted by‘essence’and‘function’resulted not from the doctrinal conflicts between Confucianism and Buddhism but from the interactions between them.


Introduction
The 'essence-function' (ti-yong 體用) 1 is a core concept in Chinese philosophy.It serves as the basic philosophical framework for all major Chinese religions.This dual concept became the foundation of the 'principle and vital force'(li-qi 理氣) which is the defining characteristic of Neo-Confucianism.
It was also the primary paradigm for the development of Buddhism in China, which distinguishes Chinese Buddhism from Indian Buddhism.Since the concept of 'essence-function'played a central role in the thought systems of both Confucianism and Chinese Buddhism, an issue has been debated concerning whether it is an exclusively Sinitic element or not.The disagreement among scholars was 1 The term ti 體 can mean'body,' 'entity,' 'substance,' 'essence,' 'system,'etc.As Charles Muller explains, its English translation is problematic.Its problematic character derives generally from the fact that Western religious and philosophical discourses are traditionally more dualistic than Eastern (Muller 2016, pp.124-26).Following the practice of Muller and other scholars, in this paper we have chosen the English word 'essence'over other alternatives.
Religions 2019, 10, 272; doi:10.3390/rel10040272www.mdpi.com/journal/religionsover its exact origin.Confucianists regarded this concept as intrinsic to Chinese indigenous religions, while Buddhists asserted that it owes its essential features to the influence of Buddhism.Although many things co-exist in the same space, they are composed of different'essences' and have no predetermined 'functions.'However, each human has many potential 'functions.' 5 The Xunzi describes entities in the phenomenal world using the terms 'essence'and 'function,' and proposes that 'essence'is a compositional principle of a thing and 'function'is a quality that 2 Wei Boyang's Zhouyi cantong qi was written in the East Han 東漢 dynasty.It was the first book of alchemy in the world, and is thus recognized as a foundational text of ancient Chinese alchemy.It is worth noting that Wei Boyang was a contemporary of Emperor Huandi 桓帝 (147-167).
is potentially possessed by a human being.Even though both terms appear together in the text, it is not clear whether or not there is a mutual relationship between them. 6 Yanwu observes that the concepts of 'essence'and 'function'originally appeared in the Zhouyi cantong qi by Wei Boyang in the Lianghan 兩漢 period (206 BCE-220).This text contains the following observation: Spring and summer are based on inner 'essence,'and autumn and winter are based on outer 'function'. 7ere is an ongoing argument about whether the'essence'and the'function'alluded to in this text are mere philosophical abstractions or just refer to concrete particularities in the physical world.Yet, Wei Boyang's use of the terms reflects a simple tenet of Confucianism, as exemplified by the concept of yin-yang 陰陽, which represents the principle of complementarity in ancient Chinese philosophy describing how seemingly opposite or contrary forces interrelate to each other.
The concept of 'essence-function'was first used as a philosophical paradigm during the Weijin Nanbeichao 魏晉南北朝 dynasty (220-589)-the period in which Wang Bi 王弼 (226-249) engaged his academic pursuits.Today, many researchers consider his thought on Xuanxue 玄學, a branch of Daoism, as a forerunner of the concept of 'essence and function' in Neo-Confucianism.They maintain that Wang Bi's use of the notion of 'root and stem'was a paradigmatic shift in the evolution of this dual concept.According to Wang Bi, 'existence'(you 有) stems from 'nonexistence'(wu 無). 8 This nonexistence can be understood as the predecessor of the concept of 'essence.'Inhis theory, each phenomenon has a 'function'caused by this essential root.9Wang Bi's idea of nonexistence is analogous to the Buddhist notion of emptiness (kong 空) proposed by the Prajñā school, in the sense that both concepts refer to the intrinsic nature of all things.As a matter of fact, Wang Bi's concept of nonexistence cannot be explained without the notion of emptiness.This is why Wang Xiaoyi 王曉毅 and Lu Cheng 呂澂 considered that Wang Bi was influenced by Buddhism. 10It is sufficiently clear that Wang Bi lived before the emergence of Chinese Buddhism in the 4 th to 5 th century; yet, this fact notwithstanding, there is a possibility that he encountered a certain type of Buddhism because his academic activities coincided with the period of the transmission and assimilation of Indian Buddhism in China during its earliest phases. 11reover, Wang Bi's ontology includes drastic changes that are not found in the Laozi 老子 and the Book of Changes (周易). 126 For a detailed interpretation of the Xunzi 10, see (Zhang 1996), pp.241-42.

The Origin in Buddhism
As discussed above, Li Yong maintained that the concept of'essence-function'was first framed by Huineng in the 7 th century.However, Sengzhao 僧肇 (384-414), a disciple of the eminent Buddhist translator Kumrajīva, had already employed it in the 4 th century.One of the most notable achievements of Sengzhao was to re-envision the theory of twofold truth (erdishuo 二諦說) through the prism of Chinese philosophy. 13He understood the twofold truth, comprised of'ultimate truth'(zhendi 眞諦) and'conventional truth'(sudi 俗諦), in terms of the concepts of'essence'and'function,'asserting that the two are inseparable.He compared 'essence and function'to 'stillness and movement.'This can be found in the following description: Even though it goes, it doesn't move; it is always still.Even though it is still, it is not stationary; it is always moving.It is still, but it always goes.Because of this, it doesn't move as it goes.Even though it is moving, it is always still.It is still, but it isn't stationary. 14is passage explains that a body moves while being still and is static as it moves.Such a state of stillness and movement is called xiangji 相卽, a concept which denotes that two phenomena are mutually identical.From the perspective of 'conventional truth,' stillness is different from movement.
From the perspective of 'ultimate truth,' on the other hand, stillness is identical to movement.They are simply different names for the same phenomenon. 15Sengzhao demonstrated that 'essence'and 'function'are also in the relationship of mutual identity (xiangji), arguing that 'essence'is in fact 'function,'and 'function'is 'essence.'Inthis way, this thought of mutual identity supersedes extreme views such as that"there is only'function,'and no'essence,' "and conversely that"there is only 'essence,'and no 'function.'"

The Conceptual Development in Buddhism
Sengzhao' s thought that'essence' and'function' are mutually identical was further developed in the Awakening of Mahyna Faith (大乘起信論, hereafter referred to as AMF).This text configures 'essence'and 'function'in the following dialectic: There is 'one mind,'and there are the two aspects of this'one mind.' 16 The mind in terms of'suchness' (zhenru 眞如) is explained as'essence;' the mind in terms of 'phenomena'(shengmie 生滅) is described as 'function.'AMFindicates that 'essence'and 'function'have an identical origin, i.e., 'one mind.'Thus,they are by nature the 13 For Sengzhao's understanding of the twofold truth, see (ZhL)  See also (Tang 2002), p. 250. 16AMF proposes the framework of one mind (一心), the two aspects (二門) of the one mind, and the three types of greatness (三大) inherent in the one mind.The mind in terms of suchness constitutes the greatness of 'essence,'while the mind in terms of phenomena represents the greatness of potentialities and the greatness of 'function.'Here,the first part of the trinity corresponds to 'essence'while the second and the third correspond to 'function.'Infact, the concept of the three types of greatness inherent in the one mind is a transitional notion that describes the process of development of 'essence-function.'Note also (AMF) 575,c23-25: 是心真如相 即示摩訶衍體故 是心生滅因緣相 能示摩訶衍自體相用故.
For more on the concept of 'essence-function'in AMF, see (Muller 2016), pp.131-33.same, but differ only in their aspect.17This idea was advanced through Sengzhao's proposal that 'essence'and 'function'are identical.
The focus of what is now called Huayan 華嚴 emphasized the identity of 'essence' and'function.'Fazang 法藏 (643-712), who was in fact the progenitor of Huayan,18 systematized his thoughts on the basis of the concept of 'essence-function.'According to him, 'essence,'which manifests itself independently, is nothing other than'function.' 19 Therefore, 'essence' and'function' in themselves are the world of truth (fajie 法界).Fazang further conceptualized 'essence'and 'function'in the context of the relationship between'principle'(li 理) and'phenomena'(shi 事), which later became one of the core terms of Neo-Confucianism.'Principle'is the fundamental law, general pattern, or innate quality that governs reality.On the other hand, 'phenomena'are events or entities as they are experienced in the empirical world.'Phenomena'are always changing and merging together, and as a totality form a 'principle,'as if hundreds of streams were running into the sea.According to Fazang, 'principle'is 'essence'and 'phenomena'are 'function.'Tobe sure, 'essence' as 'principle'has the same flavor (yiwei 一味), but it is always associated with 'function'as 'phenomena.' 20 Each and every individual 'phenomenon'is pervaded by 'principle.'Thus,all the various discrete 'phenomena'in the universe are in interaction with every other 'phenomena' on the basis of 'essence.' Chengguan 澄觀 (738-839), the fourth patriarch of the Huayan school, developed Fazang's idea of 'essence-function' as'principle-phenomena' one step further.According to him, the world of truth embraces 'principle'and 'phenomena'as a collective whole; so they cannot impede one another.
The concept of 'dependent origination'(yuanqi 緣起), a key principle in Buddhism which stipulates that all phenomena arise in dependence upon other phenomena, refers to the myriad 'functions'of 'essence.' 21In his commentary on the Avatamsaka S ūtra, Chengguan suggested as follows: Movement and stillness are inseparable and originate from one and the same root. 22 this passage, Chengguan clarifies that movement and stillness derive from one and the same root (yiyuan 一源).Elaboration of this idea can be found in his other work, Dafangguangfo huayanjing suishu yanyi chao 大方廣佛華嚴經隨疏演義鈔.In this text, Chengguan explained that the relationship between movement and stillness is identical to that between 'phenomena'and 'principle.'Just as movement and stillness originate from one and the same root, so too do 'phenomena'and 'principle.'Chengguanmaintained that this one and the same root is the 'essence'of the world of forms of metaphysical and physical flux in Yisue 易學.30All things possess 'principle,'but they manifest it differently due to the different qualities of their 'vital force.'ZhuXi argued that metaphysical'principle'provides the basis for'phenomena,'whereas physical entities are simply vectors of their metaphysical counterpart. 31Here, the'principle'is'essence'and the'vital force' that manifests empirical things in the world is 'function.'Accordingto Zhu Xi, 'principle'and 'vital force'are fundamentally synchronic, but in the conventional sense the former exists prior to the latter.It is assumed that things take on their form through the operation of their 'vital force'after the appropriation of'principle.'32Zhu Xi's'principle'-centered proposition is supported by his assertions that'principle'is transcendent in character; it exists independently; and it acts separately from the physical world.In this light, if we follow the logic of Zhu Xi's thought, 'essence'is given primacy over 'function.'

Concluding Remarks
This paper has examined the concept of 'essence-function'in the context of the Buddhist and the Confucian traditions.Discussion thus far leads us the following main points: (1) The terms 'essence'(ti) and 'function'(yong) appear already in Confucian and Daoist works such as the Xunzi and the Zhouyi cantong qi.At the same time, however, they did not constitute a hermeneutical framework for interpreting the status of things in the physical world.
(2) The paradigm of 'essence' and'function' was first employed in a philosophical context by Wang Bi who argued that the'function'of myriad things stems from nonexistence.This nonexistence was the predecessor of the concept of 'essence,'which was formed under the influence of the Buddhist notion of emptiness.
(3) Subsequently, this paradigm was appreciated by the Buddhists who came after Wang Bi.
Sengzhao understood 'essence'and 'function'in terms of the twofold truth.From the perspective of conventional truth,'essence'and'function'are different.From the perspective of ultimate truth, on the other hand, they are of mutual identity (xiangji 相卽).
(4) Post-Sengzhao Buddhists discussed the reason for the mutual identity of 'essence' and 'function' in terms of the concept of 'one mind'in the Awakening of Mahyna Faith.The 'essence'and the 'function'originate from 'one mind.'Theyare by nature identical, but differ only in their aspect.
(5) Huayan studies further developed the idea that 'essence'and 'function'share the same origin.Fazang interpreted the dual concept in terms of the relationship between 'principle' and'phenomena.' 'Essence' as'principle' has the same flavor (yiwei 一味) with'function' as 'phenomena.'Byemploying the comparison of movement and stillness, Chengguan clarified that the world of truth embraces'principle'and'phenomena'as a collective whole in which they do not impede one another.

. The Origin in Chinese Indigenous Religions
The argument on the origin of 'essence-function'emerged in the Southern Song dynasty(1127-1279)and came to a head during the period of transition between the Ming 明 (1368-1644) and the Qing 淸 (1636-1912) dynasties.Two important philosophers, Li Yong 李顒 (1613-1682) and Gu Yanwu 顧炎武 (1627-1705), extensively debated on the concept of'essence-function.'Gu Yanwu insisted that it was already an element of pre-Chin Confucianism.To demonstrate this, he attributed its origin to the Zhouyi cantong qi 周易參同契 by Wei Boyang 魏伯陽, 2 which contains the concepts of both'essence'and'function.'On the other hand, Li Yong argued that'essence'and'function'in that text denote something other than the commonly understood'essence-function.'Hemaintained that the dual concept was first formulated by the eminent Chan master, Huineng 慧能 (638-713).It is clear that the debate between Gu Yanwu and Li Yong over this concept reverberated throughout since then, suggesting important implications regarding its origin.
The debate on the concept of 'essence-function'continues in modern East Asian scholarship.In modern scholarship, however, the heated debate surrounding its origin has shifted, as the focus is now on investigating how this concept was employed in the doctrinal structures of various strands of Buddhism and Confucianism when it was theoretically developed in each religious tradition.