Dazhu Huihai (Chinese: 大珠慧海) (fl. 788) was a Chan Master in the Hongzhou School, and was a disciple of Mazu Daoyi. The Dunwu rudao yaomen lun (Treatise on the Essential Doctrine of Suddenly Entering into Enlightenment) is attributed to him. His name, Dazhu, means "Great Pearl."[1]