Very little is known of Deinon and his writings; even less can be said of Heracleides of Cyme, the third Persica author who appears in Plutarch's corpus. In all, this figure appears about eight times in the extant Greek literature. It may be, however, that use was made of his work without explicit credit. Let us begin with the literary interpretation of the references to Heracleides in Plutarch's works, turn to what we know of his Persica, and on the basis of what we can conjecture about the structure of Heracleides’ work, attempt to arrive at Plutarch's work method concerning this author.

PLUTARCH AND HERACLEIDES

The last third of the Artaxerxes does not name any source, apart from the mention of Heracleides apropos of the king's incestuous relationship with his daughter (Art. 23.6 = FGrH 689 F 7a):

Within the story of Artaxerxes’ passion for and marriage to his own daughter Atossa (Art. 23.3–5) comes this information, which is admittedly from a different source than the rest of this section. Mimicking the excess of the king who marries not only one, but two daughters, Plutarch finds evidence for this incestuous behaviour of Artaxerxes not only in one source (his main one), but in two (including Heracleides).

It would seem that Art. 23 has three parts: (a) In the first section (23.1–2) the king is portrayed positively, specifically favoured by the Greeks. He executes Tissaphernes the satrap and restrains his anger towards his mother by forgiving and appeasing her. (b) In the second segment (23.3–6), Artaxerxes is revealed as the complete opposite of Greek morality when he engages in an incestuous relationship with his daughter and adopts an arrogant attitude, believing that he is law incarnate and acts on behalf of the gods; he is presented as taking two daughters in wedlock.