The play “Oedipus the King” is a drama that is full with of irony. Oedipus had tried to get rid of his fate that he would kill his real father and get marry with his real mother, Iocaste. However, He could not escape from his terrible fate. And the play makes full about theme of sight, truth, ignorance and darkness.
Teiresias holds the key to the link between sight and blindness - for even though he is blind, he can still see and predict the future. At the end of the play, moreover, Oedipus blinds himself, because what he has metaphorically seen leaves him unable to face his family or his parents in the afterlife. As with the previous theme, sight and blindness operates both literally and metaphorically within the play. Indeed, literal sight is juxtaposed with "insight" or "foresight".
Teiresias also serves an additional role—his blindness augments the dramatic irony that governs the play. Teiresias is blind but can see the truth; Oedipus has his sight but cannot. Oedipus claims that he longs to know the truth; Teiresias says that seeing the truth only brings one pain. He can make predictions. He also knows the truth about Oedipus' identity, but the old seer doesn't want to reveal this painful reality.
When Oedipus discovers the awful truths, he gouges out his eyes, thus physically blinding himself to the reality around him; he cannot bear to look at the children he has sired, knowing they are his half-siblings.
The play is full of references to sight and truth, to ignorance and darkness imagery. All of these reinforce Sophocles' ideas about truth being a matter of perception.