Tso-chan-i

The Tso-chan-i (坐禅仪, Pinyin: Zuo-Chan-Yi, Principles of Zazen), is a short Chan Buddhist meditation manual attributed to a monk named Ch'ang-lu Tsung-tse (c. 11th century) during the Northern Song dynasty (CE 960 - 1126) which exemplifies the practice of seated meditation which aims at "sudden" enlightenment. According to Peter Gregory it is the "earliest known work of its kind in the Zen tradition." The Tso-chan-i was later revised and expanded in 1202 by Yu Hsiang and this version was published together with Tsung-tse's monastic code ("Pure Regulations of the Zen Preserve"), the earliest extant Zen monastic code, which was widely circulated.

In writing the Principles, Tsung-tse was influenced by the works of the Tiantai meditation master Zhiyi as well as by the Cultivation and Realization According to the Sutra of Perfect Enlightenment by Kuei-feng Tsung-mi (780-841). The Principles actually quotes large parts of Zhiyi's introduction to meditation, the Xiao Zhi Guan, showing the extent of the Tiantai influence on Chinese Chan. The 600-700 character text begins with a description of the traditional cross-legged meditation posture with eyes partially opened (criticizing Zhiyi for promoted closed eyes) and then outlines how the meditator is to watch his thoughts until his mind becomes unified:

Do not think of any good or evil whatsoever. Whenever a thought occurs, be aware of it; as soon as you are aware of it, it will vanish. If you remain for a long period forgetful of objects, you will naturally become unified.

Unlike the meditation works of Zhiyi, the 'Principles' doesn't outline a vipassana practice which leads to wisdom - prajña. This might be because the ideas of Tsung-tse seem to be related practices in the Chan chronicle Leng-ch'ieh shih-tzu chi and to the teachings of the East Mountain Teaching, who taught that in quieting the mind one would be able to see one's innate Buddha nature and that this was a form of sudden enlightenment. This teaching is also related to the concept of Tathatā or 'Suchness' which is derived from the Awakening of Faith in the Mahayana. Tsung-tse uses a well known metaphor to describe how practicing his kind of samadhi will lead the discovery of inherent wisdom already present in the mind:

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