Xingqi yüming 行氣玉銘 (Jade Inscription of Qi Movement)
The earliest extant textual evidence of a breathing technique relating to daoyin is an inscription on a block of jade dating from the late Warring States period (around the late 4th or early 3rd century BCE). This jade artefact, now in the Tianjin Museum, has twelve sides in the shape of a cylinder, measures 5.4 cm in height and 3.4 cm in width, and fits comfortably in the hand. Three characters are inscribed on each side, making 36 characters in all. Nine of the thirty-six characters are underscored by two lines underneath them, suggesting that these characters were intended to be read twice.
The meaning of these characters has been the subject of considerable debate, as has the original function of the object, and its precise date. Although there are only thirty-six characters, not all of them can be easily identified, resulting in differing interpretations of the text. Guo Moruo 郭沫若 (1892–1978), a renowned scholar of ancient literature and archaeology, interprets the text as follows:
行氣深則蓄，蓄則伸，伸則下，下則定，定則固，固則萌，萌則長，長 則退，退則天。天幾 (機) 舂 (動) 在上，地幾 (機) 舂 (動) 在下。順則生，逆則死。
The movement of the qi: When it becomes deep, it stores. When it stores, it extends. When it extends, it goes downward. When it goes downward, it becomes stable. When it is stable, it becomes strong. When it is strong, it begins to germinate. When it germinates, it grows. When it grows, it then retreats. When it retreats, it becomes Heaven. The dynamism of Heaven moves upwards and the dynamism of Earth moves downwards. Following it, one lives; opposing it, one dies.
Chen Banghuai 陳邦懷 (1897–1986), an epigrapher and calligrapher, has a different understanding of some of the characters and, therefore, of the text:
行氣，吞則，則伸，伸則下，下則定，定則固，固則萌，萌則長， 長則復，復則天。天其本在上，地其本在下。順則生，逆則死。
To circulate vapour: Swallow, then it travels; travelling, it extends; extending, it descends; descending, it stabilizes; stabilizing, it solidifies; solidifying, it sprouts; sprouting, it grows; growing, it returns; returning, it is heaven. Heaven – its root is above; earth – its root is below. Follow the pattern and live; go against it and die