Yuquan Shenxiu (玉泉神秀) (606?-706) (Wade-Giles: Shen-hsiu; Japanese: Jinshū) was one of the most influential Chan Buddhist masters of his day, a patriarch of the "East Mountain Dharma Gate" (Chinese: tung-shan fa-men) — the East Mountain Teaching was given the more recent designation as the "Northern School" by Shenhui (670-762). Shenxiu was Dharma-heir of Hongren (弘忍) (601–674) (Wade Giles: Shih Hung-jen; Japanese: Gunin), honoured by Empress Wu Zetian (r. 690-705) of the Tang Dynasty, and alleged author of the Guan Xin Lun (Treatise on the Contemplation of the Mind, written between 675-700), a text once attributed to Bodhidharma.
Read more about Yuquan Shenxiu: Biography, Verse Contest, Teachings, Decline of Northern Chan School