The dialogue as well as the language of the chorus also emphasizes the tragic message about the tragic life of the ill-fated Oedipus.
Oedipus Rex is an ancient Greek tragedy which is so typical of the classical tragedies that Aristotle took it as an example to define and illustrate the qualities of a tragedy. Aristotle's definition is a descriptive one (and not prescriptive); the definition of tragedy has been modified because many great tragedies have been written since without being confined to the Aristotelian features. However, it is feasible to first see this tragedy in terms of Aristotle's definition.
Aristotle defined tragedy in terms of its plot, character and action. The plot of a tragedy must consist of one, great and complete action. Each part of the play must contribute to the final tragic consequences and effect. The cause and effect must be logically linked: no external force must intervene. The main tragic character must possess great status and ideal qualities; but he must also have a weakness, though not a moral flaw —this weakness is called ‘hamartia'. The consequence of the character's own error of judgment or of his wrong action must bring the fall, from which there is no escape. This should give us the sense of inevitability, making us accept and realize the reality and the weakness of the character. The reversal and discovery must reveal to the character and the audience the cause of the character's undoing and downfall. It should not be the doing of the external forces, like supernatural forces or of fate and chance.
Besides the tragic plot, we have a typically tragic character, Oedipus. Oedipus is a tragic character because he is a great man with some ideals and with a commitment to find out the truth and cure the problem besetting is country. But like a tragic character, he has a tragic weakness. His tragic weakness is that in the confidence of what he knows or can know he becomes too careless and disrespectful towards the gods, the fate that the oracles have disclosed for him: he defies to any inner voice and wisdom with regards to fate and destiny.
Another tragic element in the play Oedipus Rex is its tragic atmosphere. From beginning to end, we are exposed to very serious and frightening situations. The dramatic conflict among the characters and the dramatic tension that builds in our minds never settles down; and there is no comic element, even like in Shakespearean tragedies. Like in a typical tragedy, the dramatist has designed even the dialogue so carefully as to create and sustain a very serious tone and mood throughout. The hopes that always lead us to fear, and the anxiety that always leads us to frustration finally contributes to the catharsis. Our false hopes and wishes as prompted and guided by the chorus finally collapse into the tragic purification of emotions, which is called catharsis or purgation (in the audience), along with the tragic change in the characters. The chorus is also a corollary element that contributes considerably in the tragic characteristics of this drama.