In his book "Tetrabiblos," Ptolemy outlined the principles of astrology as they were known in the Hellenistic world. He discussed the zodiac, planetary influences, the casting of horoscopes, and the interpretation of astrological charts for predicting events. Ptolemy's theories and methods became widely influential in Western astrology, shaping its development for centuries to come.
However, it's important to note that astrology as a practice existed long before Ptolemy and has roots in various ancient civilizations, such as Mesopotamia and Egypt. Therefore, it is not accurate to attribute the origins of astrology solely to a single individual.