The reader

From the beginning of the Antigone, Creon is fearful of a return of violence which turns into heightened suspicion of deviations from absolute adherence to his authority. His first address is orchestrated: He singles out a group of loyal followers because he suspects that some in the city are not in sympathy with his reign, or with his edict that the enemy dead, including Polyneices, lie unburied.

First he accuses the guards of collusion, then he suspects a secret cabal has bribed them. He must let go of those fantasies when he learns it was a young girl, acting alone, who disobeyed his order. When Haemon reminds him that other voices in the city did not harmonize with his, Creon is quick to find motivation for his son's error. Since even he can't credibly think Haemon has been bribed, his fertile imagination fabricates other reasons: Cherchez la femme, etc.:

Do not, my son, banish your good sense
through pleasure in a woman, since you know
that the embrace grows cold                                        {650}
when an evil woman shares your bed and home.
What greater wound can there be than a false friend? (philos kakos)
No. Spit on her, throw her out like an enemy,
this girl, to marry someone in Death's house.
I caught her openly in disobedience
alone out of all this city and I shall not make
myself a liar in the city's sight. No, I will kill her.

When Haemon spits (πτύσας), it won't be at Antigone.

the boy glared at him with savage eyes, spat in his face . . . {1231-32} 

τὸν δ᾽ ἀγρίοις ὄσσοισι παπτήνας ὁ παῖς, πτύσας προσώπῳ 

The last speaker to address Creon's judgment is Teiresias. If Antigone had a simple emotional conviction that it was wrong to leave her brother unburied, and Haemon could offer rational political and social reasons that any ruler would be wise to listen to, Teiresias doesn't begin with feeling or reason. He starts with signs (σημεῖα):

Τειρεσίας

γνώσει, τέχνης σημεῖα τῆς ἐμῆς κλύων. 
εἰς γὰρ παλαιὸν θᾶκον ὀρνιθοσκόπον 
1000ἵζων, ἵν᾽ ἦν μοι παντὸς οἰωνοῦ λιμήν, 
ἀγνῶτ᾽ ἀκούω φθόγγον ὀρνίθων, κακῷ 
κλάζοντας οἴστρῳ καὶ βεβαρβαρωμένῳ. 
καὶ σπῶντας ἐν χηλαῖσιν ἀλλήλους φοναῖς 
ἔγνων: πτερῶν γὰρ ῥοῖβδος οὐκ ἄσημος ἦν. 

Teiresias
You will understand, when you hear the signs (σημεῖα) revealed by my art. As I took my place on my old seat of augury where all birds regularly gather for me, I heard an unintelligible voice among them: they were screaming in dire frenzy that made their language foreign to me. I realized that they were ripping each other with their talons, murderously—the rush of their wings did not lack meaning (οὐκ ἄσημος). [1005]

From long experience, the prophet knows what these birds ought to sound like. But instead of what he expects, he hears an "unintelligible voice" (ἀγνῶτ᾽ ἀκούω φθόγγον). He is brought to interpret this voice because it is, at first cry, unintelligible. The sting (οἴστρῳ) of their screams (κλάζοντας) turned them into barbarous babble: βεβαρβαρωμένῳ. The onomatopoeia carries both the "babble" and the sense that the birds have begun speaking in an incomprehensible, or foreign, tongue. The tearing of talons, the strange speech, and the whir of wings (the rush of their wings did not lack meaning (ἄσημος)) all become signs that the prophet begins to read:

He interprets, or translates these foreign signs. They are foreign by virtue of being other than clear, beautiful signs. They are shrill:

nor does any bird sound out clear signs (εὐσήμους) in its shrill cries, for they have tasted the fatness (λίπος) of a slain man's blood.

οὐδ᾽ ὄρνις εὐσήμους ἀπορροιβδεῖ βοάς ἀνδροφθόρου βεβρῶτες αἵματος λίπος. 

Reading begins with the unintelligible, the screech one would rather not have to listen to. Efforts to read closely at times fail to follow Tiresias's method. How often do we "read" by attending to what makes sense, and mute, or ignore, the parts of a text that don't immediately conform, or "fit"?

Teiresias' speech is his treatise on reading. He reinforces the point that he is blind, that he is led by a child who helps him "see" the signs before he can interpret them. The treachery of sight lies in how often it is misled by appearances, where truth, often, is not found:

And it is your heart that is the source of the sickness now afflicting the city

καὶ ταῦτα τῆς σῆς ἐκ φρενὸς νοσεῖ πόλις. 

It might be worthwhile at this point to briefly ponder Teiresias's lesson as we look at the relation of dialogue to ode in the play. One way to read Antigone is to remain within the logic of the dialogues, to consider the themes of justice and power solely as they are elucidated by the speeches and stichomythia. But then, the poetry of the odes gets relegated to a kind of filler, or window dressing, between the dialogues. 

Each of the odes is packed with images that relate to the themes, yet not always in some clearly logical, or intelligible way. (The hideous blindings of the last, very dark ode, for example -- if they don't fit a certain view we have of the play's overall theme, what are they there for? Merely a few unintelligible yawps?)

Let's consider the speech of Teiresias in relation to two moments where we've encountered birds before. In the first ode (the parodos), which evoked the fear and pathos of a city threatened on all sides by murderous generals, the chorus sings of an eagle: 

He set out against our land because of the strife-filled claims of Polyneices, and like a screaming eagle he flew over into our land, covered by his snow-white wing, with a mass of weapons and crested helmets. (110-116)

ὃς ἐφ᾽ ἡμετέρᾳ γᾷ Πολυνείκους 
ἀρθεὶς νεικέων ἐξ ἀμφιλόγων 
ὀξέα κλάζων 
ἀετὸς εἰς γᾶν ὣς ὑπερέπτα, 
λευκῆς χιόνος πτέρυγι στεγανός, 
115πολλῶν μεθ᾽ ὅπλων 
ξύν θ᾽ ἱπποκόμοις κορύθεσσιν.

The "he" here is, in fact, not any particular person, but the entire army personified as a "man." The man came against Thebes because of the strife (νεικέων)-filled claims of Polyneices (the name means "much strife"), and abruptly we hear the piercing cries (ὀξέα κλάζων) of a shrieking eagle poised to swoop down and devour the city.

The piercing (ὀξὺν) shriek of a bird is also heard when the guards discover Antigone by the body of Polyneices:

she wailed aloud with the sharp cry of a grieving bird, as when inside her empty [425] nest she sees the bed stripped of its nestlings

ἡ παῖς ὁρᾶται, κἀνακωκύει πικρᾶς ὄρνιθος ὀξὺν φθόγγον

In the logic of Creon's world, the tears of a sister weeping for her brother could never possess the power, the terminal violence, of Polyneices' white eagle. It would make no sense for the light dust spread by a girl to cause greater ruin than the united wrath of the Seven. Or for her grief to pull apart a dynasty. Yet it does. Creon's heart (φρενὸς) is sick. That which we do not readily understand could be a sign whose very absence of sense deserves a look. An enigma. It was a woman with eagle's wings and the power of a lion that brought Oedipus to himself.

What appears to say nothing, to be utterly "Greek to us," might in truth speak volumes about nothing but ourselves.

Blind poets and prophets

In addition to Thamyris, Milton mentions Homer, Phineas, and Tiresias in his invocation to Book III:

Blind Thamyris and blind Mæonides, [ 35 ]

And Tiresias and Phineus Prophets old.

The common thread is that all were blind. At least three were blinded by the gods as a form of punishment, or limitation. Thamyris, as we've seen, lost his sight for his hubris in challenging the muses.

Phineas

Phineas features in the story of Jason and the Argonauts: [He] was said to be a son of Poseidon, or of Phoenix, and had the gift of prophecy. Zeus, angry that Phineas revealed too much of the plans of the gods, punished him by blinding him and setting him on an island with a buffet of food. However, he could eat none of it because the harpies, vicious, winged women, stole the food out of his hands right before he could eat.^[1] This continued until the arrival of Jason and the Argonauts. They sent the winged heroes, the Boreads, after the harpies. They succeeded in driving the monsters away but did not kill them, as a request from the goddess of the rainbow, Iris, who promised that Phineas would not be bothered by the harpies again. It is said that the Boreads were turned back by Iris at the Strophades.[2]As thanks, Phineas told the Argonauts how to pass the Symplegades.

Tiresias

Tiresias was a prophet of Apollo. According to the mythographic compendium Bibliotheke,^[3] different stories were told of the cause of his blindness, the most direct being that he was simply blinded by the gods for revealing their secrets. An alternate story told by the poet Pherecydes was followed in Callimachus' poem "The Bathing of Pallas"; in it, Tiresias was blinded by Athena after he stumbled onto her bathing naked.^[4] His mother, Chariclo, a nymph of Athena, begged Athena to undo her curse, but the goddess could not; instead, she cleaned his ears,^[3] giving him the ability to understand birdsong, thus the gift of augury.

Homer

The poet's name is homophonous with ὅμερος (hómēros), meaning, generally, "hostage" (or "surety"), long understood as "he who accompanies; he who is forced to follow", or, in some dialects, "blind".^[19] The assonance itself generated many tales relating the person to the functions of a hostage or of a blind man. In regard to the latter, traditions holding that he was blind may have arisen from the meaning of the word both in Ionic, where the verbal form ὁμηρεύω (homēreúō) has the specialized meaning of "guide the blind",^[20] and in the Aeolian dialect of Cyme, where ὅμηρος (hómēros) was synonymous with standard Greek τυφλός (tuphlós), meaning 'blind'.^[21]

It should be noted that the names of these famous Greek poets and prophets come after the description of the poet's chief haunt:

Thee Sion and the flowrie Brooks beneath

That wash thy hallowd feet, and warbling flow,

and before the evocation of the nightingale, whose bloody tale has been evoked by Ovid, Dante, Chaucer, Shakespeare, Eliot and many others:

Then feed on thoughts, that voluntarie move

Harmonious numbers; as the wakeful Bird

Sings darkling, and in shadiest Covert hid

Tunes her nocturnal Note.