In Oedipus Rex, how did Sophocles use situational and dramatic irony to convey the theme of fate vs. free will?

makes a number of
choices that create situational . For example, he chooses not to believe the very people who
tell him the truth about himself and his parentage. He calls the blind prophet, , to the palace
at Thebes so that he can get some honest answers, and he obviously believes that Teiresias is an
authority to be trusted or else he would not do so. However, when Teiresias tells Oedipus that
it would be better for Oedipus not to know the truth, Oedipus becomes enraged. He taunts
Teiresias for being blind--ironically, since Oedipus is so figuratively blind himself--and he
even accuses Teiresias of conspiring against him with his brother-in-law (and uncle), . Then,
when Teiresias gives Oedipus what he's asked for--the truth--Oedipus refuses to believe him.
Through this example of situational irony, we see how Oedipus's free will and the exercise of
his terrible pride leads him to the fate already laid out for him.

's
audience would have known that...