But the happiness of the Trojan prince does not last. Calchas, who desires to see his daughter, contrives that she shall come to him in an exchange of prisoners. Inexpressible is the sorrow of Troilus when he learns of this design.[236] He prays the gods, if they wish to punish him, to take from him his brother Hector or Polissena, but to leave him his Criseyde.[237] Nor is Criseyde less affected.[238] Pandarus, when appealed to, suggests that Troilus shall take the girl, if need be, by force: a marriage seems to have been out of the question.
"Pensato ancora avea di domandarla
Di grazia al padre mio che la mi desse;
Poi penso questo fora un accusarla,
E far palese le cose commesse;
Nè spero ancora ch' el dovesse darla,
Sì per non romper le cose promesse,
E perchè la direbbe diseguale
A me, al qual vuol dar donna reale."[239]
In fact, Cassandra has already discovered that her brother is in love with a lady of no birth, the daughter of a wretched and vulgar priest. So Troilus decides to have a last meeting with Criseyde before she goes, to contrive with her what is to be done. At this meeting the lovers swear eternal fidelity[240] and Criseyde promises to return to him in Troy in ten days' time. Then in that same day Diomede delivers one prisoner and takes Criseyde back with him to the Greek camp.