In view of the fact that the Ten Suchnesses represent the Ultimate Truth, and the Ultimate Truth consists of both the Relative and the Ultimate, the Relative and the Ultimate are defined by Chih-i in relation to the Ten Dharma-realms. … [T]he first nine realms are ascribed by Chih-i to the Relative, and the last Buddha-realm to the Ultimate. Among the ten realms, the six realms (hell-dwellers, hungry ghosts, animals, asuras, humans and heavenly beings) are the lower state of existence, and the four realms (śrāvakas, pratyekabuddhas, bodhisattvas, and Buddhas) are the state of sagehood (Liu-tao Ssu-sheng). Since the Ten Dharma-realms are divided into the Relative and the Ultimate, like that of the Ten Suchnesses, the ten realms should also contain the three meanings in terms of the Threefold Truth.

1. With regard to the Ten Dharma-realms that contain the meaning of Emptiness, this means that all ten realms belong to the Dharma-realm (Ch., Fa-chieh; Skt., dharmadhātu), the former relies on the latter (Neng-i), and the latter as the foundation is what the former relies upon (So-i). Thus, the ten realms form the Ten Dharma-realms. All of the Ten Dharma-realms are fundamentally empty and enter the realm of Emptiness (K’ung-chieh).
2. With regard to the Ten Dharma realms that contain the meaning of the Provisional, this refers to the separation of the ten realms (Shih-chieh Chieh-ko) due to their differences between the lower states of existence and the state of sagehood:
   

   “Because of their different lots, separated causes and effects, and distinctive features of the profane and sacred states, the ten realms are differentiated from each other.”

   Their differences are related to the conventional existence, with which the Ten Dharma-realms enter the realm of the Provisional (Chia-chieh).

3. With regard to the Ten Dharma-realms that contain the meaning of the Middle Way, this means that the Middle Way can be inferred from the principle or truth that is embodied by the Ten Dharma-realms:
   

   “These Ten [Dharma-realms] are all identical to the dharmadhātu and encompass all dharmas. All dharmas tend toward hell, and do not transcend this destiny. [The dharmadhātu] itself is the principle [of reality], and since it does not depend on anything, it is called the dharmadhātu. The same is also true [for all destinies] all the way up to the Buddha Dharma-realm.”

   The principle or truth is what the dharmadhātu denotes, and the principle is referred by Chih-i to the Middle Way. Therefore, the Ten Dharma-realms enter the realm of the Middle Way (Chung-chieh).

The connections between the Ten Dharma-realms and the Ten Suchnesses are displayed in a statement by Chih-i:

“One Dharma-realm embraces the Ten Suchnesses, and the Ten Dharma realms embrace one hundred Suchnesses.”

Meanwhile,

“One Dharma-realm embraces the other nine Dharma-realms, and hence, there come to be one hundred Dharma-realms and one thousand Suchnesses.”

(Vol. 2, Page 73-74)

provisional. The true reality is a single integrated unity, and yet, it contains three facets. The Ultimate Truth is a single integrated unity, and yet, it contains three facets, which is neither vertical nor horizontal. In Chih-i’s terminology, vertical (Shu) and horizontal (Heng) indicate a conceptual understanding of reality (consisting of time and space), in which various dharmas are distinguished as having a length from beginning to end (i.e., time), and as having a range of vastness (i.e., space). Therefore, they exist either horizontally or vertically. Neither vertical nor horizontal indicates a reality that is beyond conceptualization. In this reality, all dharmas that contain the Threefold Truth are simultaneously existent. There is no distinction among them, and therefore, they are considered as neither horizontal nor vertical. Any one of the dharmas represents all dharmas, and all dharmas are included in a single dharma. Chih-states:

“When meanings are expressed through words, Emptiness is identical to the Provisional and the Middle Way. When Emptiness is clarified in terms of ‘suchness’, Emptiness of one thing leads to Emptiness of all things. When “suchness” is specified to explicate the characteristics [of dharmas], the Provisional of one thing comprises the Provisional of all things. To discuss the Middle Way as it is, the Middle Way of one thing embodies the Middle Way of all things. They are not one, two, and three, and yet, they are one, two, and three. They are neither horizontal nor vertical, and are named the Ultimate Truth.”

(Vol. 2, Page 72-73)

In Chih-i’s opinion, the distinction among the Three Truths (Emptiness, the Provisional, and the Middle Way) is only so that people can comprehend them easily. Actually, these Three Truths are embedded in each other. When Emptiness is taken into account, the aspects of the Provisional and the Middle Way are also empty — a reality of lacking substantial Being. When the Provisional is taken into account based on the view of Emptiness, all entities bear names as conventional existence a reality of variety. On the basis of Emptiness, this view of the Provisional is non-attachment to the provisional existence. When the Middle Way is taken into account, all entities are both empty and provisional. (Vol. 2, Page 73)

Extended interpretation of the Dharma of Sentient Beings (Kuangming Chung-sheng-fa)

The Dharma of Sentient Beings is addressed in two aspects: Fa-shu (numerical categories of the Dharma of Sentient Beings), and Fa-hsiang (characteristics of the Dharma of Sentient Beings).

Numerical categories of the Dharma of Sentient Beings (Fa-shu)

This aspect introduces the Ten Suchnesses (Shihju-shih) and the Ten Dharma-realms (Shih-fa-chieh) as the numerical categories of the Dharma of Sentient Beings. According to Chih-i, the phrases of the Ten Suchnesses are derived from the Lotus Sūtra, and these Ten Suchnesses can describe the characteristics of reality. Chih-i terms the Ten Suchnesses as the “Ultimate Truth of all dharmas” (Chu-fa Shih-hsiang). They are: “suchness of appearance” (Ju-shih-hsiang), “suchness of nature” (Ju-shih-hsing), “suchness of substance” (Ju-shiht ‘i), “suchness of power” (Ju-shih-li), “suchness of function” (Ju-shihtso), “suchness of causes” (Ju-shih-yin), “suchness of conditions” (Jushih-yüan), “suchness of effects” (Ju-shih-kuo), “suchness of retributions” (Ju-shih-pao), and “beginning-and-end-ultimately-alike of its suchness” (Ju-shih Pen-mo Chiu-ching Teng). To sustain his argument that the Ten Suchnesses are the Ultimate Truth of all dharmas, Chih-i declares that the Ten Suchnesses contain three meanings in terms of the Threefold Truth (Emptiness, the Provisional Existence, and the Middle Way), when they are read in three different ways. Inasmuch as the Threefold Truth is the comprehensive view of reality and constitutes the Ultimate Truth of the Middle Way, the Ten Suchnesses that contain the meaning of the Threefold Truth can be certainly taken to characterize the Ultimate Truth. (Vol. 2, Page 71)

[I]n order to elaborate the Dharma of Sentient Beings, Chih-i brings forth the concept of the Ten Dharma-realms (hell-dwellers, hungry ghosts, animals, asuras, humans, heavenly beings, śrāvakas, pratyekabuddhas, bodhisattvas, and Buddhas), as sentient beings are what constitute the Ten Dharma-realms. The first nine realms are said by Chih-i to belong to the Relative Truth, and the Buddha-realm to the Ultimate Truth. Each of the ten realms is characterized by the Ten Suchnesses (appearance, nature, substance, power, function, causes, conditions, effects, retributions, and beginning and end ultimately-alike). Whereas the Ten Suchnesses are regarded by Chih-i as the general characteristics of the Ten Dharma-realms, the Ten Suchnesses are viewed as the Ultimate Truth of all dharmas. Hence, the Ten Suchnesses are the characteristics of the Ultimate Truth. Seeing that the Ultimate Truth is possessed by the Ten Dharma-realms that consist of the Relative and Ultimate, this Ultimate Truth embraces both the Relative and the Ultimate. Chih-i’s interpretation of the Dharma of Sentient Beings aims at associating it with the Dharma of Buddha, for the latter concerns the Buddha’s knowledge of the Relative and the Ultimate, with which the Buddha is able to conceive the Ultimate Truth that embraces the whole Dharma-realm. The Dharma of Mind, on the other hand, as Chih-i’s category of approaching the Ultimate Truth of Buddhahood includes the former two types of the Dharma. This is to say that the Ten Dharmarealms that are characterized by the Ten Suchnesses as the Ultimate Truth of dharmas are contained in one’s mind. One’s mind that embraces the whole universe is based on Chih-i’s view that the Buddha-nature is possessed by all sentient beings. Since the Buddha-nature is inherent in all beings, contemplating one’s mind is the ultimate approach to attain Buddhahood. To Chih-i, if the Buddha-nature is considered to be the invisible state of Buddhahood, the realization of Buddhahood is only the matter of manifesting this Buddha-nature, i.e., one’s enlightenment is the visible state of Buddhahood. Therefore, the Dharma of Mind introduces the practical approach in terms of mind contemplation, through which Buddhahood can be realized. (Vol.2, Page 70)