In China, Dōgen first went to the leading Chan monasteries in Zhèjiāng province. At the time, most Chan teachers based their training around the use of "gōng-àn"s (Japanese: "kōan"). Though Dōgen assiduously studied the kōans, he became disenchanted with the heavy emphasis laid upon them, and wondered why the sutras were not studied more. At one point, owing to this disenchantment, Dōgen even refused Dharma transmission from a teacher. Then, in 1225, he decided to visit a master named Rújìng (如淨; J. Nyōjo), the thirteenth patriarch of the Cáodòng (J. Sōtō) lineage of Zen Buddhism, at Mount Tiāntóng (天童山 "Tiāntóngshān"; J. Tendōzan) in Níngbō. Rujing was reputed to have a style of Chan that was different from the other masters whom Dōgen had thus far encountered. In later writings, Dōgen referred to Rujing as "the Old Buddha". Additionally he affectionately described both Rujing and Myōzen as .