Edwin G. Pulleyblank
The collection of poems attributed to Hanshan may span the entire Tang Dynasty as Edwin G. Pulleyblank asserts in his study "Linguistic Evidence for the Date of Hanshan". Wu Chi-yu in "A study of Han-shan" identifies him as the monk Zhiyan (智岩, 577–654), but that has been disputed by Paul Demiéville among others. The "Encyclopedia of China" gives his date as around 712 and after 793. Jia Jinhua came to the conclusion, after a study of Chan phrases in some 50 of the poems, that this particular group of poems may be attributable to the Chan monk Caoshan Benji (840–901). However, the dates for both Zhiyan and Caoshan Benji contradict Hanshan, who says that he was much older than either.