Several attempts to establish a system of categorizing the Buddhist Canon had been made as a means to synthesize diverse Buddhist doctrines. However, … there was not a single theory that could perfectly arrange the whole teaching of the Buddha systematically and justifiably until the emergence of Chih-i. He has formulated a systematic classification P’an-chiao, and has made it the primary recourse of justification for the consistency of all the Buddhist doctrines as a whole. His system of classification consists of three aspects.

1. First, the Buddha’s whole teaching career is arranged in five chronological periods that correspond to the five flavors of dairy products, upon which the doctrines that are expounded in these periods are introduced.
2. The second aspect is the method the Buddha uses to expound his doctrines in terms of sudden, gradual, indeterminate, and secret, which are related to the five periods.
3. Finally, based on the chronological arrangement, the Buddha’s teachings are categorized into the Four Teachings. As we have mentioned above, the Fourfold Teaching is discussed throughout the Hsüan-i (Profound Meaning of the Lotus Sūtra) , and it is so significant that it is the primary principle in systematizing Buddhist doctrines and practices. (Page 136)

 
The Profound Meaning of the Lotus Sutra: Tien-tai Philosophy of Buddhism

Through this study, we come to realize the unique contribution of Chih-i in terms of sign interpretation. That is, truth can be penetrated by means of correctly understanding the arbitrary language of nature. Truth can be exposed through interpreting various signs. For Chih-i, the interpretation of sign becomes a means to demonstrate his own philosophy, whereby his thought is proved to be akin to the principle of the Ultimate Truth. This indicates that Chih-i’s interpretation of the Lotus Sūtra is not just the discourse for speculative philosophy, but is intended to embody Chih-i’s own philosophy in practice, through which his own system of understanding Buddhism as a whole is presented. What Chih-i concerns about is no longer an idea or a metaphysical problem that remains in the domain of discourse, but the methodological and hermeneutical approaches that can demonstrate his philosophy in practice. Ultimately, the goal of his sign interpretation is educational and soteriological. That is, Chih-i strives to convey visually what the Ultimate Truth is, how we can better conceive and understand the profound truth, and how we can approach the attainment of truth through the revelation of his perfect harmonization philosophy. (Page 134)

With different numerical categories, different patterns are formed to concretely express Chih-i’s idea of what a perfect harmonization philosophy should be. First, the use of the category number ten stands for the visual image of completeness in terms of horizontal and vertical dimensions. Second, the use of the category number six is to unfold Chih-i’s perfect harmonization philosophy with the pattern of succession that denotes the nature of completeness. Third, the use of the category number five draws a pattern of circle akin to the five periods of the teachings of the Buddha that can be considered as occupying the five directions. We discern that Chih-i’s use of numerical category five denotes the affirmation of all teachings of the Buddha, while emphasizing the supremacy of the Lotus Sūtra as the centralizing force. Fourth, the use of the category number four depicts a pattern of a square, with which all the Buddhist doctrines are legitimated. Fifth, the use of the category number three draws a pattern of circle, denoting an integrated reality, in which all three aspects of the Threefold Truth are mutually identified. Sixth, the use of the category number one is to bring forth the Ultimate Truth as the representation of the single reality of Buddhahood. Thus, we come to a conclusion that these six numerical categories depict Chih-i’s perfect harmonization philosophy in terms of non-separation, non-differentiation, mutual identification, affirmation of all existing things, and integration of all aspects of reality. (Page 133-134)

Similar to the pattern number three, the category number five also forms a circle. The five directions including the center and the other four directions revolving around it … symbolize the supremacy of the central point, but at the same time are all-encompassing with all directions equally in their own positions. Likewise, we may consider that the center of the five periods of the teaching is occupied by the Lotus Sūtra, symbolizing the period of apogee and the supremacy of this doctrine. However, the supremacy of the period of the Lotus Sūtra does not negate the importance of the other four periods. Without the relative doctrines expounded in the four periods to prepare the audiences for the revelation of the final doctrine, the audiences would not be able to comprehend the message delivered in the ultimate teaching of the Lotus Sūtra. With the previous four periods revolving around the last period of the Lotus Sūtra, the former periods are affirmed, in a sense that they have their own unique positions, and are thus embraced by the last period. The pattern of this circle that consists of five divisions affirmatively renders the characteristics of Chih-i’s perfect harmonization philosophy in an all-embracing manner. Forming a coherent unity, all existing things are gathered together under the leadership of the central point.

Chih-i’s use of numerical category of “ten” is usually arranged in an ascending order such as in the case of the Ten Dharma-realms. According to Chih-i, each realm is inclusive of the other nine realms, forming one hundred realms. Furthermore, each realm contains ten different characteristics (Ten Suchnesses), rendering one thousand worlds in all. Each of these thousand worlds has three divisions—sentient beings, the five aggregates, and the space we live in. In total, this accounts for three thousand worlds. And these three thousand worlds are all possessed by one single mind. If one mind contains different worlds, this is a pattern of extension, starting from a single beginning point (one mind), but one mind can expand to the whole universe. From the vast perspective of the three thousand worlds to the point of a single mind, there occurs a pattern of contraction, returning from the end of the phenomenal world to the beginning of the phenomenal world. Such a pattern of extension and contraction supports Chih-i’s theory of one instant thought containing three thousand dharmas (I-nien San-ch ‘ien), and the whole universe is realized as nothing but the act of mind. This theory leads to a further conclusion Chih-i intends to draw, that is, liberation is possible for all living beings, because it is the mind that plays the key role and determines one’s destination. From the realm of Buddha to the realm of hell, there is only the substance where one’s mind abides. (Page 129-130)

One is equated with Tao—the ultimate unity of Heaven (e.g. Yang), Earth (e.g. Yin) and Man (Multitudes). Similarly, the number “one” in Chih-i’s system is the representation of the Ultimate Truth. This Ultimate Truth is absolute, inasmuch as it reveals the authentic nature of reality. Therefore, this Ultimate Truth refers to the one vehicle of Buddhahood, the ultimate goal for all living beings to strive for, which is the theme of the Lotus Sūtra. The Three Vehicles (śrāvaka, pratyekabuddha, and bodhisattva) are all unified under the Buddha-vehicle. (Page 129)

The affirmation of the mundane world is more known to be associated with Confucian ideology, which is concerned with more or less the fulfillment of one’s moral duty as a person in society. Though the contents of this affirmation of the mundane world in Taoism, Confucianism, and Chih-i’s philosophical system are quite different, their positive attitudes towards phenomena are the same. One is reminded of Chih-i’s well-known statement that underlies his affirmation of worldly phenomena: “Every color and fragrance is none but the Middle Way.” If every worldly entity manifests nothing else but the truth of the Middle Way, it is of course not to be negated, but to be affirmed.

Number four is extremely important in Chih-i’s system of classification. The well-established Buddhist notions, such as the Four Noble Truths and the Twelvefold Causality are corresponded by Chih-i’s own theory of the Four Teachings. Coherently, his theories of the four types of the Four Noble Truths and the four types of the Twelvefold Causality are formulated corresponding to the Four Teachings. In my opinion, the number four that is embodied by the Four Teachings is consciously or unconsciously significant to Chih-i. Number four represents the four seasons of a year, signifying a complete cycle of succession. With different seasons, different kinds of plants are able to grow. Our understanding of Chih-i’s use of number four is that, like the function of all four seasons which allow all plants to grow and to ripen, the Fourfold Teaching is designed by Chih-i to signify that it addresses all sentient beings with different capacities. (Pages 126-127)

Number “five” in Chinese culture elaborates the change of worldly phenomena. This is to say that the fundamental set of five is composed of wood, fire, earth, metal, and water. They are the five basic elements that construe the world, and each of them is connected to one another in sequence and rotates one after another in a full circle (i.e., wood produces fire, fire produces earth, earth produces metal, metal produces water, and water produces wood). These Five Elements (Wu-hang) incorporate all other sets of five things, in a sense that all of them correspond to the Five Elements, such as five directions (east, west, south, north, and center), five musical notes (Kung, Shang, Chüeh, Chih, Yü), five internal organs (heart, liver, spleen, lungs and kidneys), five grains (rice, two kinds of millet, wheat and beans), and so forth. Although these numerical categories of five represent different phenomena, each of them is simply a different name for the same principle the Five Elements denote (since all of them correspond to the Five Elements). That is, the universe (whether as microcosm or macrocosm) is presented as a complete circle of change among five elements (each of which is related to one another). Therefore, any set of these five phenomena forms a circle of correspondence among each other and symbolizes completion and perfection.

It is interesting to note that Chih-i’s Five Sections (five categories of analysis or five layers of the abstruse meaning), i.e., name, substance, gist, function, and teaching, are arranged for the interpretation of the Lotus Sūtra. Whether intentionally or not, this number five corresponds to the number of words “Miao-fa Lien-hua Ching” that constitute the title of the Lotus Sūtra. While these five words as the title of the Lotus Sūtra is underlined the profound principle, the Five Sections are designed to explore the profound meaning that is contained in each word. Furthermore, the Five Periods (Wu-shih) in Chih-i’s system of classifying the teaching of the Buddha (P’an-chiao) are able to incorporate the whole of the Buddha’s teachings chronologically. In addition, the five flavors of dairy products are employed to analogize these five periods, denoting the perfection of the complete circle of the Buddha’s teaching career.

Number “six” plays an important role in the system of hexagrams in the Book of Changes, which reflects in six lines forming a complete pattern of succession of six positions of Yin and Yang. This suggests that what “six” represents is the completion of the pattern of the universe represented by a hexagram, which is constituted by the doubled three powers (that can refer to heaven, earth, and man). The pattern of the hexagram is formulated by the elements of Yin and Yang, each of which is employed in succession, forming six lines. It is interesting to note that Chih-i uses a similar way to define the Origin and the Traces in terms of using the numerical category of six and in terms of the two elements being employed in succession. This indicates that Chih-i defines the Traces and the Origin in six groups in terms of the six polar concepts (i.e., “principle” and “phenomenal appearances”, “principle” and “teaching”, “teaching” and “practice”, “substance” and “function”, “ultimate” and “relative”, and “present” and “past”), and each of the following groups of definition takes the meaning of its proceeding one. With the employment of these six polar concepts, the Traces and the Origin are defined in succession. Such a way to define the Traces and the Origin denotes a complementary relation between these two entities. Moreover, instead of the two elements of Ying and Yang that constitute the hexagram as the representation of a complete pattern of the universe (possibly intended by Chih-i himself), this pattern is also completed with number six. However, since this pattern is defined in the Buddhist context, it is spoken of in terms of time (embodied by the Traces) and space (embodied by the Origin).