Zongmi's lifelong work was the attempt to incorporate differing and sometimes conflicting value systems into an integrated framework that could bridge not only the differences between Buddhism and the traditional Daoism and Confucianism, but also within Buddhist theory itself.
Confucianism, Daoism, Buddhism
Much of Zongmi's work was concerned with providing a dialogue between the three religions of China: Confucianism, Daoism and Buddhism. He saw all three as expedients, functioning within a particular historical context and although he placed Buddhism as revealing the highest truth of the three, this had nothing to do with the level of understanding of the three sages, Confucius, Laozi and Buddha, (who Zongmi saw as equally enlightened) and everything to do with the particular circumstances in which the three lived and taught. As Zongmi said:
Since encouraging the myriad practices, admonishing against evil, and promoting good contribute in common to order, the three teachings should all be followed and practiced. [However] if it be a matter of investigating the myriad phenomena, exhausting principle, realizing the nature, and reaching the original source, then Buddhism alone is the ultimate judgment.
Zongmi's early training in Confucianism never left him and he tried to create a syncretic framework where Confucian moral principles could be integrated within the Buddhist teachings.
Sudden and Gradual Enlightenment
Zongmi tried to harmonize the different views on the nature of enlightenment. For the Chan tradition, one of the major issues of the day was the distinction between the Northern line, which advocated a "gradual enlightenment" and the Southern line's "sudden enlightenment".
Coming from the Southern Chan tradition, Zongmi advocated the Southern teachings of sudden enlightenment. But he also saw both as according with the teachings of the Buddha. He wrote:
It is only because of variations in the style of the World Honored One’s exposition of the teachings that there are sudden expositions in accordance with the truth and gradual expositions in accordance with the capacities [of beings]…this does not mean that there is a separate sudden and gradual [teaching].
Although the sudden teaching reveals the truth directly, and results in a "sudden" understanding that all beings are Buddhas, this does not mean that one attained Buddhahood rightaway. Hence, Zongmi advocated "sudden enlightenment" followed by "gradual cultivation". This gradual cultivation was to eliminate all remaining traces of defilements of the mind, that prevented one from fully integrating one's intrinsic Buddha-nature into actual behavior.) According to Zongmi:
"In terms of the elimination of hindrances, it is like when the sun immediately comes out, yet the frost melts gradually. With respect to the perfection of virtue, it is like a child which, when born, immediately possesses four limbs and six senses. As it grows, it gradually develops control over its actions. Therefore, the Hua Yen [Avatamsaka sutra] says that when the bodhicitta is first aroused, this is already the accomplishment of perfect enlightenment."
To explain this, Zongmi also used the metaphor of water and waves found in the Awakening of Faith treatise. The essential tranquil nature of water which reflects all things (intrinsic enlightenment) is disturbed by the winds of ignorance (un-enlightenment, delusion). Although the wind may stop suddenly (sudden enlightenment), the disturbing waves subside only gradually (gradual cultivation) until all motion ceases and the water once again reflects its intrinsic nature (Buddhahood). However, whether disturbed by ignorance or not, the fundamental nature of the water (i.e., the mind) never changes.
Classification of teachings
As with many Buddhist scholars of the day, doctrinal classification (p’an chiao) was an integral part of Zongmi's work. Zongmi's "systematic classification of Buddhist doctrine is itself a theory of the Buddhist path (mārga)."
He provided a critique of the various practices which reveal not only the nature of Chan in Tang Dynasty, but also Zongmi's understanding of Buddhist doctrine.
The Buddha's Teachings
Zongmi arranged the Buddha's teachings into five categories:
◦The teaching of men and gods (人天教),
◦The teachings of the Hinayana (小乘教),
◦The teaching of the Mahayana on phenomenal appearances (大乘法相教),
◦The teaching of the Mahayana on destroying appearances (大乘破相教) and
◦The teaching of the Ekayāna that reveals the nature (一乘顯性教) (intrinsic enlightenment).
In Zongmi's teaching, the "nature" of each person is identical with Buddha-nature, which is emphasised in Chan. He stated, "To designate it, initially there is only one true spiritual nature, that is not born, does not die, does not increase, does not decrease, does not become, and does not change." In giving this teaching the highest position, Zongmi altered the classification of Fazang, who regarded the Hua-yen teachings to be the supreme teachings and established the common denominator of Chan and Huayen teachings within the "One Vehicle" (Ekayāna).
Zongmi's Analysis of the Five Different Types of Chan
In his discussion of the various meanings of Chan, Zongmi explains the meaning of chan (< Sanskrit dhyāna "meditative states") in terms of five categories as befits the differences in human aptitudes.
(1) The first is that form of meditation practiced by non-Buddhists that seeks rebirth in the higher realms and avoidance of rebirth in the lower realms. It corresponds to the teachings of Confucianism and Daoism.
(2) The second is that form of meditation practiced by Buddhists who have a correct understanding of cause and effect and who seek rebirth in the higher realms and avoidance of rebirth in the lower realms. It corresponds to the teaching of humans and gods in Zongmi's classification of Buddhist teachings.
(3) The third is that form of meditation practiced by Hīnayāna Buddhists who have realized the emptiness of self.
(4) The fourth is that form of meditation practiced by Māhayāna Buddhists who have realized the emptiness of all things (dharmas) in addition to the emptiness of self.
The first four types of chan all involve the progressive mastery of a hierarchical sequence of meditative stages and are therefore gradual, in contradistinction to the fifth type of chan, which was introduced by Bodhidharma and which is sudden.
(5) The fifth is that form of meditation practiced "based on the sudden insight that one’s own mind is intrinsically pure, that from the beginning it is devoid of the defilements, that originally it is fully endowed with the nature of untainted wisdom, that this mind is the Buddha, and that ultimately there is no difference between them"—which Zongmi refers to as the chan of the supreme vehicle.
Analysis of Mind
Zongmi saw enlightenment and its opposite, delusion, as ten reciprocal steps that are not so much separate processes, but parallel processes moving in opposite directions.
Zongmi follows the One Vehicle interpretation of the Yogachara analysis of the Eight Consciousnesses that is found in the Laṅkāvatāra Sūtra and the Awakening of Faith in the Mahayana in describing the phenomenology of the mind.
In Zongmi's vision, the Real Mind is the true nature which is revealed at the moment of awakening. Before this awakening, True Mind is deluded by thoughts and wrong visions. The phenomenal appearance of this true mind is the Buddha-nature and its deluded manifestation is the store-house consciousness, or citta, the eighth and fundamental consciousness in Yogachara thought. From this deluded consciousness springs manas, the grasping consciousness, which is the seventh consciousness. From there springs the cognitive mind (sixth consciousness) and the five sense-consciousnesses.