Summary This essay explores a broad theme fundamental to the study of time in Chinese science,
namely the persistent denial by scientists and philosophers for the past two thousand years that full
knowledge of the patterns underlying physical phenomena is attainable by rational and empirical
means. These thinkers maintained that empirical study must be pursued alongside other ways of
knowing that in general are concerned with being and experience outside space and time: meditation,
concentration, disciplined intuition, self-examination, and so on.
Statements to this effect from writings in various fields of science from about 100 B.C. to the
seventeenth century are considered, but in order to pay special attention to thought about time, the
essay is mainly concerned with discussions of indeterminacy in the technical literature of mathematical
astronomy. Early statements reflect a crisis in the ability to reliably predict astronomical phenomena
previously documented in my Cosmos and Computation in Early Chinese Mathematical Astronomy
( Leiden: E. J. Brill, 1969). By the eighth century this argument was being used not only to explain the
failure of predictive techniques but also as ammunition in attacks on innovators by conservative
holders of astronomical sinecures in the imperial civil service. Beginning in the eleventh century,
discourse about the limits of empirical knowledge was transformed by astronomers better prepared
than their predecessors to explore methodological and epistemological aspects of their science, and by
a few philosophers who made these aspects an important part of their thought. The notion of
indeterminacy in their hands became an organizing center for explorations in what would now be
called the philosophy of science. This seemingly obscurantist notion was fruitful in clarifying the
difference and potential conflict between accuracy and precision (late twelfth century), to give only one
of several examples.
For two thousand years time has been a natural focus of interest in the study of Chinese thought, and of scientific thought in particular. Of the uncountable Chinese commentaries on and studies of the Book of Changes, for instance, not many have ignored the preoccupation of that classic with time shaping the cosmos and man's perception of nature. One of the earliest commentaries, the so-called Great Commentary, interpreted the cosmic way, the Dao, in this famous passage: "As the sun moves on, the moon comes; as the moon moves on, the sun comes. As sun and moon impel each other light is produced. As the cold goes, the heat comes; as the heat goes, the cold comes. As cold and heat impel each other the year is formed. What moves on contracts; what comes expands. What contracts and what expands influence each other, producing what furthers [man's activities]."
So we see that it is the harmoniously alternating interplay of opposites that forms time; it is time that underlies cosmic process; and it is cosmic process that provides a pattern for human reflection and conduct. As a line in the next passage of the same commentary tells