Zi Collection, Middle Volume Radical: Earth (tǔ) Page 230, Entry 14 According to the Jade Chapters (Yupian), this is the ancient form of the character for cliff or boundary (yin). Detailed commentary can be found in the section on characters with six strokes. The Record of the True Source (Huainanzi) states: The wilderness where reeds and rushes grow in thickets extends to a place with no boundaries.