In his influential Poetics , Aristotle sets guidelines for the form of tragedy using Oedipus the King as his ideal model. Tragedy is usually concerned with a person of great stature, a king or nobleman, who falls because of hubris, or pride. There are unities of time, place, and, most importantly, action. Action may be thought of simply as motive or "movement of spirit": in Oedipus the King the action for most of the play is "find Laius' killer and stop the plague in Thebes." The action in Antigone is "preserve rightness and order in Thebes." Antigone is a strange case because the "movement-of-spirit" arguably comes from two directions: Antigone and Creon are both championing what is right, but they define rightness through different sets of values. Key elements include the moments of reversal and recognition, although not every tragedy has these moments. Reversal means a great and unexpected turn in events when the action veers around and becomes its opposite. Antigone experiences no reversal, but Creon does: at the Chorus' prodding, he finally backs down and listens to the advice he has been given, turning against the preservation of the kind of order he cherishes. Recognition means that a character gains sudden and transformative understanding of himself and the events he has experienced, moving from ignorance to knowledge. In Antigone , Creon finally recognizes that he has been misguided and that his actions have led to the death of his wife and son. Ideally, according to Aristotle, the reversal and the recognition hit at the same instant, as they do in Oedipus the King . While the Poetics are indispensable for the student of Greek drama - and, indeed, drama in general - Aristotle's theories should not be a straitjacket. Aristotle's guidelines make it difficult to appreciate the genius of Euripides, and by the standards of the Poetics , the great tragedies of Shakespeare would be failures. Aristotle is writing from a particular time and place, and he is also speaking from a very specific artistic sensibility. He may be the first word on Greek tragedy, but he is not the last.