Ten Bulls or Ten Ox Herding Pictures (十牛; Japanese: jūgyū, Chinese: shíniú) is a series of short poems and accompanying pictures used in the Zen tradition to illustrate the stages of a practitioner's progression towards the purification of the mind and enlightenment, as well as his or her subsequent return into the world while acting out of wisdom.
The calf, bull or ox is one of the earliest similes for meditation practice. It comes from the Maha Gopalaka Sutta (Majjhima Nikaya 33). It is also used in the commentaries, especially the one on the Maha Satipahna Sutta (Digha Nikaya 22) and the Satipahna Sutta (Majjhima Nikaya 10). With the spread of Buddhism throughout South-East Asia, the simile of the bull also spread.
The well-known ten ox-herding pictures emerged in China in the 12th century. D.T. Suzuki mentions four Chinese versions of the Oxherding Pictures, by Ching-chu (Jp. Seikyo)(11th century), Tzu-te Hui (Jp. Jitoku)(1090-1159), an unknown author, and Kuòān Shīyuǎn (Jp. Kaku-an) (12th century). The best-known of these is the version by Kuòān Shīyuǎn.
Probably the first series was made by Ching-chu (清居, Jp. Seikyo) (11th century), who may have been a contemporary of Kuòān Shīyuǎn. In Ching-chu's version only five pictures are being used, and the ox's colour changes from dark to white, representing the gradual development of the practitioner, ending in the disappearance of the practitioner.
Tzu-te Hui (自得慧暉, Zide Huihui, Jp. Jitoku) (1090-1159) made a version with six pictures. The sixth one goes beyond the stage of absolute emptiness, where Ching-chu's version ends. Just like Ching-chu's version, the ox grows whiter along the way.
A third version by an unknown author, with ten pictures, was most popular in China. It belongs to the Ching-chu and Tzu-te Hui series of pictures, and has a somewhat different serie of pictures compared to Kuòān Shīyuǎn's version. The 1585-edition contains a preface by Chu-hung, and it has ten pictures, each of which is preceded by Pu-ming's poem, of whom Chu-hung furtherwise provides no information. In this version too the ox's colour changes from dark to white.
The best known version of the oxherding pictures was drawn by the 12th century Chinese Rinzai Chán (Zen) master Kuòān Shīyuǎn (廓庵師遠, Jp. Kaku-an Shi-en), who also wrote accompanying poems and introductory words attached to the pictures. In Kuòān Shīyuǎn's version there is no whitening process, and his series also doesn't end with mere emptiness, or absolute truth, but shows a return to the world, depicting Putai, the laughing Buddha. According to Chi Kwang Sunim, they may also represent a Zen Buddhist interpretation of the ten Bodhisattva bhumi, the ten stages on the Bodhisattva-path.