Her force, her intellect, and her strength of will all exceed her station. The Greeks, though they have some respect for her, often treat her smugly because of her sex and her barbarian origins. She is surrounded by people less intelligent and resourceful than she, but social power and respect is theirs. Because she is an outsider to normal order, she behaves without restraint or morality. Her genius, denied an empire to build, will instead be used on the smaller playing field of personal revenge.
Manipulation is an important theme.
Medea, Jason, and Creon all try their hand at manipulation. Creon has made a profitable match between his daughter and Jason, hoping to benefit from Jason's fame as the hero of the Golden Fleece. But Medea is the master of manipulation. Medea plays perfectly on the weaknesses and needs of both her enemies and her friends. Medea plays to Creon's pity, and to the old king's costly underestimation of the sorceress.