One of the major schools of Chinese Buddhism.whose highly abstract philosophy is generally accepted as the highest expression of Buddhist thought in China. Two aspects of this school's teachings are notable: doctrinal classification and the theory of unobstructed interpenetration of all phenomena.
The school derives its name from the scripture that forms its primary object of study, the Avataṃsaka Sūtra (Chin., Hua-yen ching), a text notable for its effort to describe the way the world appears to an enlightened Buddha. Indeed, the sūtra was said to have been preached by Śākyamuni directly after his attainment of enlightenment (bodhi). The scripture had been known and studied in China at least since the year 420, when Buddhabhadra completed the first translation in 60 fascicles. A group of scholars around Tu-shun (557–640) were attracted to the ‘Chapter on the Bodhisattva Grounds’ in the eighth fascicle of this translation. Consequently, they were called the Ti-lun (‘discourse on the grounds’) school, and this is commonly taken as a forerunner of the Hua-yen school itself. Tu-shun's disciple Chih-yen (602–68) also specialized in study and preaching the sūtra. However, credit for the foundation of the Hua-yen school proper goes to Chih-yen's disciple Fa-tsang (643–712; also called Hsien-shou), although, in deference to his illustrious predecessors, he is listed as the school's third patriarch. Fa-tsang, perhaps because of his central Asian ancestry, had some facility with Indian languages, and so was called to the capital Ch'ang-an to work in Hsüan-tsang's translation bureau. He broke with the latter, and later was asked by Empress Wu Tse-t'ien to assist the Indian monk Śikṣānanda with a new translation of the Avataṃsaka, which came out in 704 and consisted of 80 fascicles. However, it was not Fa-tsang's skill as a translator, but his facility in expounding the abstruse philosophy of the sūtra in accessible language and appealing metaphors that helped attract imperial patronage and consolidated the school's position.
After Fa-tsang, the line of patriarchs continued with Ch'eng-kuan (738–820 or 838). Also versed in Indian languages, Ch'eng-kuan assisted the monk Prajñā to produce a 40-fascicle version of the last section of the sūtra, the Gaṇḍavyūha, which added new material to the end and helped bring the sūtra to a more satisfying conclusion. In addition, Ch'eng-kuan's teaching activities and his prolific commentaries on the sūtra further established the school on a secure basis.
The fifth and last patriarch was Tsung-mi (780–841), who was also acknowledged as a master in the Ch'an school. Like his two predecessors, he achieved great eminence for his learning and teaching, and served in the imperial court, assuring continued patronage. However, four years after his death.the next emperor instigated the most wide-ranging persecution of Buddhism in China prior to the Cultural Revolution in the 20th century, and this school, dependent as it was on royal patronage for maintenance of its academic facilities and the upkeep of its masters, perished at that time.
Before the foundation of the Hua-yen school, Chih-i (538–97), founder of the T'ien-t'ai school, had already established criteria for taking the highly varied corpus of Buddhist texts and teachings and placing them into an overall structure that brought order and explained discrepancies (see p'an-chiao). However, his system had developed some deficiencies: it used three different criteria to generate three different schemes, and it failed to take into account the teachings of the Fa-hsiang school, which had not been established until after Chih-i's death.