Ptolemy I Soter rivals after Alexander's death. For example, Arrian's account of the fall of Thebes in 335 BC ("Anabasis" , a rare section of narrative explicitly attributed to Ptolemy by Arrian) shows several significant variations from the parallel account preserved in Diodorus Siculus (17.11–12), most notably in attributing a distinctly unheroic role in proceedings to Perdiccas. More recently, J. Roisman has argued that the case for Ptolemy's blackening of Perdiccas and others has been much exaggerated. Ptolemy personally sponsored the great mathematician Euclid. He found Euclid's seminal work, the "Elements", too difficult to study, so he asked if there were an easier
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,