This paper analyzes the Zen methodology of Hakuin Ekaku 白隠慧鶴 （1686-1769） and Dahui Zonggao 大慧宗杲 （1089-1163） to make the following three points:
（1） Hakuin, inheriting the method of kōan contemplation systematized by Dahui, presented the following sequence of Zen practice leading to seeing one’s Buddha-nature: first one practices zazen and contemplates a kōan; then one expands one’s state of mental concentration obtained by this beyond zazen to all of one’s activities; and finally one breaks the bounds of samādhi and sees one’s Buddha-nature. Hakuin saw his own Buddha-nature by this method at the age of twenty-four, and he advocated it to others.
（2） While Daihui emphasizes the attainment of enlightenment through constant kōan contemplation in one’s every action, Hakuin emphasized practice after satori, which consists of the two elements of seeking enlightenment and saving sentient beings. Hakuin particularly emphasized the latter, and he realized its importance by a divine revelation from the kami of Kasuga that the moment he would cease to benefit others he would surely descend into suffering. Hakuin was nervous lest he ever cease to benefit others for even a moment, and this vitalized his practice.
（3） Hakuin devised a new method of instruction as he taught the dharma to benefit others when he began issuing three kinds of certificates: one given to those who had seen their Buddha-nature, a second to those who understood the relationship between seeking enlightenment and saving sentient beings, and third to those who had inherited his dharma. Hakuin would assess the levels of each of his disciples with these three kinds of certificates to encourage their continued practice.
