Time

As in other civilizations, China has delved into both the sensible and the abstract, analytical aspects of time. Social-political time traditionally used sixty-day and sixty-year cycles, and a ten-day "week" framed plans, or divinations, about the near future (these schemata are seen in 1200 B.C.E. oracle records and remained ubiquitous). Usually, Chinese days were broken into twelve "hours" and 100 subunits ("minutes"). Archaeology provides examples of early imperial (c. 250–100 B.C.E.) clocks used by officialdom: one type was a gnomon chronometer—a small disk notched for diurnal shadows, in one case with sixty-nine subunits. Cosmic boards of the Han period (206 B.C.E. to 220 C.E.) mechanically aligned an inner wheel indicating segmented slices of time (seasons and hours) with cosmological categories and ecliptic constellations appearing on a square background. Third-century B.C.E. texts preserved in the western deserts refer to regulations for local functionaries in assigning times for signaling, delivering documents, and scheduling projects. Finally, in all time periods court experts performed time-related functions: calendar ritualists assigned dates for sacrifices and ceremonies; astrologers interpreted astral and meteorological portents, often drawing on computations for eclipses; and scholar-officials not only interpreted and debated the findings of such experts but also worked on genealogies and on philological research to correct primordial calendars, both of which played a role in political legitimacy.

Chinese thinkers did not devise philosophies, pedagogies, or keys of the sort developed in the West concerning time, and the context was chiefly driven by the state's need for cosmological and ritual correctness, and in some cases by cosmological and apocalyptic notions conveyed in Buddhist and Daoist scriptures. Yet China also produced its own sophisticated metaphysics of time—more accurately, sociocosmic "timing." The 3,000-year tradition known as "the Changes," or Yi jing (Book of changes), employed a set of arrayed lines, classically three or six per set, which was called a gua. The lines were associated with numbers; they could change in character (yin and yang) and concomitantly in numeric value; and they moved in and through other, associated, gua by means of permutations. Like dates and times of birth in Western astrology, they were used to predict career and health and to establish an individual's place in a local social or political network. The Yi jing achieved a high place in China's pedagogical, scholarly, and even political life, as influential in its way as the West's Bible. We should approach the gua system as an essential part of Chinese natural philosophy, a locus of scholarly work that linked broad areas of inquiry like cosmic patterns and regularity, divination, alchemy, chronology, medicine, and numerical principles.