In the Footsteps of Angels: Medieval Arabic Astrology

Illustration of different phases of the moon, from manuscript of the Kitab al-Tafhim by Al-Biruni (973-1048).

As the newly formed Muslim caliphate extended beyond the Arabian Peninsula, it encountered Persian, Hellenistic, and Indian forms of astrology, integrating them into a refined science that would reach its medieval peak in Baghdad, a city whose fortune and fate would be foretold by the stars.

Firmicus Maternus: A skeptic among the stars

Port of Messina, Sicily, Italy

A lawyer turned astrologer turned devout Christian, Firmicus Maternus penned the eight-book Mathesis, one of the lengthiest extant works on Hellenistic astrology in Latin, giving sixteen centuries of readers insight into astrological practices during the Roman Empire.

Vettius Valens: Soldier of Fate

Alexandria in the late 18th century, painting by Luigi Mayer

Know to the Arabs as “Al-Rumi”, Vettius Valens gained near-mythical status in the East while his fame was largely eclipsed by Ptolemy in the West but his Anthologies remains the most important source contemporary readers have for the foundations and techniques of Hellenistic astrology.

Claudius Ptolemy: A Sage Head in the Clouds

A depiction of the Ptolemaic Universe as described in the Planetary Hypotheses by Bartolomeu Velho (1568)

The works of Hellenistic polymath Ptolemy of Alexandria outlined the Western view of the cosmos that would survive until the Copernican revolution and defined the rational-causal view of astrology still largely ascribed to today.

Hellenistic Astrology: Rationalizing Fate

Artistic Rendering of the Library of Alexandria, based on some archaeological evidence.

Merging Babylonian star worship with indigenous Egyptian astronomy and Greek mathematics and philosophy, Hellenistic astrologers crafted the fourfold technical structure of astrology that weathered two millennia to survive as the foundational elements of modern astrology today.

The Fault in our Stars: Marcus Manilius and Western Astrology

The opening page (top section) of the poem Astronomica by the Roman poet Manilius

As the Roman Empire rose, absorbing the trappings of Hellenistic culture, one writer penned the oldest surviving complete treatise on the art of astrology. Part poetics, part mathematics, Manilius’ Astronomica offers a glimpse of the core concepts and Stoic philosophy underlying both Hellenistic astrology and the beginning of modern Western science.

Astrology, Power and the Roman World

Capricorn – The Sun sign of Caesar Augustus (63 BC - AD 14)

In the Roman Empire, knowledge of the stars could get you killed—or help you kill others. Discover how the science of reading the heavens became a powerful political tool in the Roman world.