Treasury of the True Dharma Eye Zen Master Dogen's Shobo Genzo
"Treasury of the True Dharma Eye (Shobo Genzo, in Japanese) is a monumental work, considered to be one of the profoundest expressions of Zen wisdom ever put on paper, and also the most outstanding literary and philosophical work of Japan. It is a collection of essays by Eihei Dogen (1200--1253), founder of Zen's Soto school."--Google books.