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Dongshan Liangjie is best known as the founder of the Caodong school of Zen Buddhism, which became Sōtō Zen in its Japanese rendering. His student, Caoshan Benji (840-901) provided the ‘Cao’ part of the name.
Dongshan is said to have written the Verses on the Five Ranks which showed the progression of understanding of the relationship between absolute and relative reality. The teaching poem Precious Mirror Samadhi (Hōkyō Zammai) is also attributed to Dongshan.
A monk is said to have asked Dongshan, “When the cold season comes, where does one go to avoid it?”
Dongshan said, “Why not go where there is no cold?”
The monk said, “Where is the place there there is no cold.”
Dongshan said, “When it’s cold, the cold kills you. When it’s hot, the heat kills you.”
Further Reading
Dongshan Liangjie in the Denkōroku (Record of the Transmission of the Lamp)
Just This is It: Dongshan and the practice of suchness – Taigen Dan Leighton
Dongshan’s Five Ranks – Ross Bolletor