In the conclusion to his book The Babylonian Theory of the Planets, Noel Swerdlow remarked that “from the earliest omen texts and Diaries to the latest almanacs and ephemerides, for century after century, generations of teachers and students observed, calculated, and also pondered deeply how these irregular but periodic phenomena were to be described, reduced to precise rules, and computed for the past, present, and future.” But the Babylonian scholars, he continued, “have left no record of their theoretical analyses and discussions.” One of the tasks of the historian of Babylonian astronomy, therefore, is to try to reconstruct its development from texts which are the direct result of its practice—in particular texts containing systematic records of observations and texts which contain predicted phenomena calculated either using past observations (goal-year astronomy) or arithmetical systems (mathematical astronomy)—aided by a smaller number of texts which provide instructions for making calculations. A very small number of texts—I know of only two or three—seem to bear witness to a Babylonian scholar actively working on the development and/or testing of methods of predicting astronomical phenomena, but they provide no more than occasional glimpses into the process of the development of methods of computing astronomical phenomena.