(1689-1769). Almost single-handedly revitalized Japanese Rinzai Zen in the eighteenth century. At that time, much of the concern of the Gozan Zen monasteries was caught up with powdering young novices as Geisha and the hand signals used to indicate the place and time of a tryst. Hakuin returned Rinzai Zen to an emphasis on zazen and questioning through koan study and practice. Most current Rinzai Lineages derive from him.

While much of his Teachings emphasize an approach to life as a problem to be struggled with, his sense of humor was ribald and sometimes scatological. One of his funniest texts was the Dokugyo Shingyo or "Poisonous Words on The Great Prajna Paramita Heart Sutra". Many useful versions of translated texts have been done by Norman Waddell and have appeared in the journal Eastern Buddhist in the 1980s; some have have been published as books. And, of course, the late Philip Yampolsy's "The Zen Master Hakuin" should not be forgotten. Hakuin's verses and calligraphies still dynamically convey something of the caustic wit of this revolutionary monk.