Final answer:
Medea views Jason as evil because of his betrayal, which leads her to feel justified in her revenge. Euripides uses this dynamic to explore themes of injustice, the psychological complexity of characters, and the fallibility of humans, even in the realm of gods and heroes.
Step-by-step explanation:
In Euripides' play Medea, Medea casts Jason as evil because she feels profoundly wronged and betrayed by him. Jason's abandonment of Medea for another woman undermines the loyalty and sacrifices she made for him, which included murdering her own brother and betraying her father. This betrayal is particularly terrible because it represents a grave injustice toward Medea, exacerbating her alienation and despair, leading her to commit heinous acts out of revenge.
Euripides' work often encourages the audience to question antiquated conventions and the social order, highlighting the human struggle and the injustices faced by groups such as women and foreigners. While Medea is certainly portrayed as a criminal, her rationality and calculated actions are a response to the cruel heart of Jason, and the injustices she has suffered. In doing so, Euripides promotes a psychological understanding of human motivation, moving from darkness to light, and questioning the actions of the gods.
The tragic element in the play is showcased by the extreme actions Medea takes against her children, the princess, and King Creon, shedding light on the human capacity for both greatness and monstrosity when faced with insurmountable emotional turmoil.