The Tetrabiblos

The Tetrabiblos, written by the ancient Greek philosopher Claudius Ptolemy in the 2nd century, is a foundational work in astrology. It outlines the principles of astrological practice and how celestial bodies influence human affairs. The title means "Four Books," as it is divided into four sections covering topics such as the nature of the stars, the zodiac, planetary influences, and the significance of astrological predictions. Ptolemy's work synthesized earlier astrological knowledge, making it a key text for both ancient and modern astrology, influencing many cultures and continuing to be referenced in contemporary astrological discussions.