He argued that Shinsei chose "井 (pronounced "sei" in Japanese, "jing" in Chinese)" because it had been commonly seen around Changan areas since the period of the Tang Dynasty, but he said that his Japanese name was unknown.
「井」姓は唐の時代から長安周辺に多い姓であり、それを採用したと主張し、日本名に関しては不明と主張。