Using Aristotelian analysis, the nurse can be identified as a stock character.
Being bound in service to Medea, the nurse exemplifies the assumed role of a servant in Greek times. She states, "our masters’ fortunes when they go awry make good slaves grieve and touch their hearts." As the Nurse recounts on Medea's previous history, she makes it clear that she knows Medea very well. She also makes it clear that she knows what Medea is capable of, and has a pretty good idea of what is about to happen. However, although she knows that it Is very likely that Medea will commit violent acts, she can find no fault in her master. She states "Into the house without delay, come not near her eye, approach her not, beware her savage mood, the fell tempest of her reckless heart. In, in with what speed ye may. For ’tis plain she will soon redouble her fury; that cry is but the herald of the gathering storm-cloud whose lightning soon will flash; what will her proud restless soul, in the anguish of despair, be guilty of?"
While the chorus expresses sympathy for Medea, they object when Medea wishes to slay her own children. The chorus wishes that Medea would not commit the act. However, the nurse, knowledgable of what Medea will probably do, states "and I much do dread that she will plunge the keen sword through their hearts." It is important to remember that while she finds no comfort in the acts Medea will commit, she also finds no fault in Medea. This is because as a faithful servant, Medea cannot do so. All of the Nurse's assertions are that of sympathy.
When the chorus asks the nurse to try to convince Medea to accept the council they offer, the Nurse states "This will I do; but I doubt whether I shall persuade my mistress." While the nurse offers that the reason for this might be a refusal to listen to anyone due to her anguish, there is another inference that can be made here. Because the nurse is seen as lower than Medea, her advice bears no validity to Medea, who is of a higher power than she. *Few edits to be made, more points to come