 100 AD) Book of Han that calls him a "fangshi" (方士 [literally "technique master"] "alchemist; magician; exorcist; diviner").Holmes Welch proposes the "fangshi" were among those whom Sima Qian described as "unable to practice" Zou Yan's arts, and says while Zou "gradually acquired alchemistical stature, he himself knew nothing of the art.It was probably developed by those of his followers who became interested in physical experimentation with the Five Elements."