What did Ptolemy’s Tetrabiblos teach about astrology?

In his work Apotelesmatika, later known as the Tetrabiblos (or "Four Books"), Ptolemy sought to establish astrology as a legitimate, albeit inexact, science.1

He taught that the heavens exert physical effects on terrestrial life, and he aimed to place these astrological practices on a sound basis. While Ptolemy accepted the validity of traditional astrological doctrines, he revised their details to align with an Aristotelian conception of nature, matter, and change. Consequently, his framework for astrology was driven by the interplay of basic physical qualities, such as hot, cold, wet, and dry.1