Ptolemy I Soter way to master it. According to Proclus Euclid famously quipped: "Sire, there is no Royal Road to geometry." Ptolemy I Soter Ptolemy I Soter (; , "Ptolemaĩos Sōtḗr" "Ptolemy the Savior"; c. 367 BC – January 282 BC) was a companion and historian of Alexander the Great who succeeded to his empire. Ptolemy became ruler of Egypt (323–282 BC) and founded the Ptolemaic dynasty which ruled it for the next three centuries, turning Egypt into a Hellenistic kingdom and Alexandria into a center of Greek culture. Ptolemy was the son of Arsinoe of Macedon by either her husband Lagus or
Ptolemy IV Philopator Ptolemy IV Philopator Ptolemy IV Philopator (, "Ptolemaĩos Philopátōr" "Ptolemy, lover of his Father"; 245/4–204 BC), son of Ptolemy III and Berenice II, was the fourth Pharaoh of Ptolemaic Egypt from 221 to 204 BC. The decline of the Ptolemaic dynasty began under the reign of Ptolemy IV. Among the children of Ptolemy IV Philopator and his sister-wife Arsinoe III of Egypt was Ptolemy V Epiphanes, who married Cleopatra I Syra, daughter of Antiochus III the Great and Laodice III. Ptolemy IV's reign was inaugurated by the murder of his mother, and he was always under the dominion of favourites,