A common description of the eighth century Chan establishment was:
In Kiangsi the master was Mazu; in Hunan the master was Shitou.
People went back and forth between them all the time, and those
who never met these two great masters were completely ignorant.
Shitou jousted with Mazu, and they often swapped students, Mazu sent his pupils on their way with a wink and the advice that Shitou was "slippery." This legendary master was forebear of three of the five "houses" of Chan arising after the Great Persecution of 845, although the only one of the three surviving is the Caoshan (Ts'ao-tung), which arose during the later Tang and early Five Dynasties (907-960) period and remains today as Japanese Soto.
In this lesson we look at two masters in Shitou's lineage, Dongshan and his disciple Caoshan. These two masters are so closely associated with each other that heir names were used together to form the name of their Zen school, Caodong.