Remember that in Greek Tragedy the protagonist was always a person of noble birth who is good at heart, but their hubris (overwhelming pride) causes them to make a terrible mistake. They are brought to their knees when confronted by this mistake, creating in the audience a feeling of catharsis, which is defined as the purging of fear and pity-- fear that if this good person could make such a mistake it could happen to anyone and pity in that this good person has gone through such terrible suffering as a result of their mistake. Frequently they are surrounded by a host of other characters who have also suffered because of that mistake. There is also a chorus, representing the audience, who
comments on the action and ultimately shares the moral of the drama.