It cannot be overemphasized that System A had no analogous precursor, and thus that – unlike virtually all succeeding scientific theories – its invention was a radical departure from anything which preceded it. Consequently, we can say almost nothing with confidence about its motivation, which cannot have been directed at the shortcomings of a (non-existent) prevailing theory, nor seemingly at any urgent practical need, since we have still no evidence of how it was employed. Indeed, how little we know of the circumstances of its origin is reflected in the fact that we do not even know for certain its author’s name.
The crucial step – apart from conceiving the desirability and imagining the feasibility of constructing a comprehensive mathematical model of this complex set of variable phenomena – was the separation and successful modeling of the effects of lunar and solar anomaly on the intervals between syzygies. The crux of this development was the initial construction of a model depicting the variations due to lunar anomaly of the intervals between syzygies.
One of the fundamental tools of Babylonian astronomy was the concept of period relation which equated Π phenomena of one sort with Z of another.
In each case the period relation implied that variations associated with the second phenomenon recurred after Π instances of the first phenomenon, and thus that Π phenomena = Z cycles of variation.
* the Substitute King ritual, practiced extensively during the reigns of Esarhaddon and Ashurbanipal, in which a substitute “king” (and queen) would be appointed to absorb the unfavorable effects of an adverse eclipse, which would be expunged from the kingdom by their subsequent deaths.
Source: John P. Britton. Studies in Babylonian Lunar Theory: Part I. Empirical Elements for Modeling Lunar and Solar Anomalies.
Arch. Hist. Exact Sci. 61 (2007) 83–145. Digital Object Identifier (DOI) 10.1007/s00407-006-0121-9