Petosiris

(Πετόσιρις), an Egyptian priest and astrologer, who is generally named along with Nechepsos, an Egyptian king. The two are said to be the founders of astrology, and of the art of casting nativities. Suidas states that Petosiris wrote on the right mode of worshipping the gods, astrological maxims, ἐκ τῶν ἱερῶν βιβλίων (which are often referred to in connection with astrology), and a work on the Egyptian mysteries. But we may infer from a statement made by Vetius Valens, of which the substance is given by Marsham (Canon Chronicus [ed. Lips. 1676], page 479), that Suidas assigns to Petosiris what others attributed partly to him and partly to Nechepsos. For his ῎Οργανον Α᾿στρονομικόν, or ψῆφος σεληνισκή, containing astrological principles for predicting the event of diseases, and for his other writings, Fabricius (Bibl. Graec. 4:160) may be consulted. To the list given by him may be added a translation into Latin by Bede of the astrological letter of Petosiris to Nechepsos, entitled De Divinatione Mortis et Vitce (Bed. Opera [ed. Col. Agripp. 1612], 2:233, 234). His name, as connected with astrology, was in high repute early in Greece, and in Rome in her degenerate days. This we learn from the praises bestowed on him by Manetho (5:10), who, indeed, in the prologue to the first and fifth books of his Apotelesmatica, professes only to expand in Greek the prose rules of Petosiris and Nechepsos ("divini illi viri atque omni admiratione digni"), and from the references of Pliny (Hist. Nat. 1:23; 7:49). But the best proof is the fact that, like our own Lilly, Petosiris became the common name for an astrologer, as we find in Aristophanes, quoted by Athenaeus (3:114, c) in the fortysixth epigram of Lucilius (Jacobs, Anthol. Graec. 3:38), whence we learn the quantity, and in Juvenal (6:580). Marsham has a full dissertation on Nechepsos and Petosiris in the work above quoted (pages 474-481).