Under the common premise that everyone has buddha-nature (foxing 佛性) and original mind (benxin 本心), there are different ways of thinking about how to relate one’s ‘original self’ as a buddha to one’s living, physical ‘actual self’. There are four types of thought in the history of Tang-Song Chan Buddhism. The first is the so-called ‘Northern’ Chan 北宗禪, which seeks to overcome the ‘actual self’ and restore the ‘original self’ through seated meditation. The second is the Mazu 馬祖 (709–788) lineage of Chan, which treats the two as one. The third type of Chan is the Shitou 石頭 (710–790) lineage which, while criticizing the Mazu lineage, grasps the relationship between the two as one and one as two. The fourth is Dahui’s 大慧 (1089–1163) kanhua chan 看話禪 (Chan of Phrase-observing), which returns to the first type of thought and adds the new technique of koan 公案 to it. They each had a strong influence on Medieval Japanese Zen Buddhism, with Bankei 盤珪 (1622–1693) inheriting the second type, the Sōtō 曹洞 school inheriting the third type, Hakuin 白隱 (1686–1769) inheriting the fourth type, and Dōgen 道元 (1200–1253)—in order to transcend both the second and the fourth types—producing a unique reflection on the honshō myōshu 本證妙修 (‘Wondrous cultivation in fundamental realization’).
