Vettius Valens

Vettius Valens was born around 120 CE, most likely in Antioch, and was a slightly younger contemporary of Claudius Ptolemy, though the two astrologers show no sign of having known each other's work and represent two quite different traditions within Hellenistic astrology, Ptolemy the philosophically minded systematizer and Valens the practicing technician. Valens describes travelling widely through Egypt in search of specific astrological doctrines and teachers he judged worth learning from, gathering techniques into his own practice rather than working from a single inherited system.

He wrote his major work, conventionally called the Anthology, across roughly 150 to 175 CE, and it is generally judged to be substantially complete by his death around 175. Almost nothing else of his biography survives independently of what he says of himself in the text, which is itself unusually candid by the standards of ancient technical writing, including passages of personal reflection on the astrologer's craft and its difficulties. Nothing is known of any formal training he received, and unlike several later Hellenistic astrologers he claims no divine or legendary transmission for his method, presenting it instead as a working technician's accumulated craft, refined through practice and correction over a working lifetime rather than received from any authoritative source.

The Anthology, nine books in Greek, is the longest surviving astrological treatise from antiquity and the single richest source for how Hellenistic astrology was actually practiced rather than only theorized. Valens included more than a hundred sample nativities drawn from his own case files, complete with his working calculations, making the text an unusually direct window onto real professional method rather than an abstract exposition.

Modern reconstruction of Hellenistic technique, including the systems of Arabic Parts and Egyptian planetary terms that the atlas describes across its astrological content, draws heavily on Valens alongside Ptolemy and the fragmentary earlier sources both of them preserve. The standard critical edition is David Pingree's 1986 Teubner text; Valens has no ancient biography beyond his own book, so essentially everything known of him as a person, rather than as a technical author, is inferred from what he chose to say about his own training and travels within it. Where Ptolemy's Tetrabiblos aimed to give astrology a philosophical justification within a broader natural science, Valens made no such argument and simply assumed the discipline's validity, a difference in temperament that later historians of astrology have used to characterize the whole distinction between astrology's theoretical and its practical wings in the ancient world.