who was he?
A mathematician, astronomer and astrologer.
Ptolemy
Claudius Ptolemy (; , "Klaúdios Ptolemaîos" ; ; AD) was a mathematician, astronomer, geographer and astrologer who wrote several scientific treatises
what is serpens? A constellation of the northern hemisphere. who discovered it? Ptolemy.
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Ptolemy [SEP] Introduction
Claudius Ptolemy (; , "Klaúdios Ptolemaîos" ; ; AD) was a mathematician, astronomer, geographer and astrologer who wrote several scientific treatises, three of which were of importance to later Byzantine, Islamic and Western European science. The first is the astronomical treatise now known as the "Almagest", although it was originally entitled the "Mathematical Treatise" () and then known as "The Great Treatise" (). The second is the "Geography", which is a thorough discussion of the geographic knowledge of the Greco-Roman world. The third is the astrological treatise in which he attempted to adapt horoscopic astrology to the Aristotelian natural philosophy of his day.