In antiquity, the expertise of the Babylonians in matters of the heavens was legendary and the roots of both western astronomy and astrology are traceable in cuneiform tablets going back to the second and first millennia BC. The Heavenly Writing discusses the place of Babylonian celestial divination, horoscopy, and astronomy in Mesopotamian intellectual culture. Focusing chiefly on celestial divination and horoscopes, it traces the emergence of personal astrology from the tradition of celestial divination and the use of astronomical methods in horoscopes. It further takes up the historiographical and philosophical issue of the nature of these Mesopotamian 'celestial sciences' by examining elements traditionally of concern to the philosophy of science, without sacrificing the ancient methods, goals, and interests to a modern image of science. This book will be of particular interest to those concerned with the early history of science.