Aristotle believed this was the finest tragedy because the Oedipus recognition of the truth coincides with the reversal of his fortunes.
The "reversal of fortunes" that Aristotle mentions in THE POETICS refers to Oedipus's tragic fall, from revered king of Thebes to an eyeless beggar banished by his own decree. Around line 1182, Oedipus realizes that all of the information he has been gathering in the play has been pointing at him, and worse, that he has doomed himself by swearing the man responsible for the plagues will be punished. Where this is the moment of reversal or whether it is when he exits from the house having blinded himself is a matter of debate, but either way, it is around this point in the play that his fortune changes because of his tragic and insatiable desire to know the truth.
