The story of ancient astrology is one of continuity and of change. On the one hand there is a remarkable inertia often revealed in astrological writings. At the extreme, you can find a text of the sixth century, such as that of John the Lydian, containing passages about celestial omens which could have been copied from the cuneiform tablets of the first millennium BCE. As for the texts in the Catalogue of Manuscripts of Greek Astrologers, it is hard to tell from the state of the theoretical development whether a work is late Byzantine or preserves the earliest Hellenistic writings to survive. Who could say for certain, if it were not for the sources mentioned, whether an extract came from Tiberius’ astrologer Thrasyllus, one of the first to bring Hermetic astrology to Rome, or from the fourteenth-century collection of Eleutherius Eleus?
There is continuity too in the world reflected in the predictions of astrological texts. Here we find an amalgam in which the sharp lines distinguishing Hellenistic culture from Greco-Egyptian, from Roman and from the turbulent times of the Late Empire, are blurred. This is partly a reflection of the way in which some aspects of quotidian existence did not change very dramatically over this long period. The questions of clients remained concentrated on similar concerns, on health, wealth, social status and the family, and the answers did not need to differ much in successive eras. People could always ask questions about the kinds of diseases they might suffer, whether they would be richer than their parents and how they would make a living, and what kind of marriages they would have, and receive similar answers. The predictions preserved a certain vagueness which allowed them to travel through time without needing much alteration. Even in the case of predictions tied to a particular geopolitical situation, as in the case of those attached to eclipse-