Why does Oedipus blind himself in Oedipus Rex?

After he
accusesof trying to take his throne, and the seerof being blind to the truth in Scene
I--"Why, he is no more clairvoyant than I am!"-- comes to realize that in his
, he has ironically placed his maledictions upon himself rather than on the
seer or Creon. Before he learns the truth, Oedipus articulates this curse: 

May I never see the day! Never!

Rather let me
vanish from the race of men'

Than know the abomination destined me!

Then, in Scene 3, Oedipus learns the terrible truth and
exclaims,

O Light, may I look on you for the last
time!

I, Oedipus,

Oedipus, damned in his birth, in his
marriage damned,

Damned in his blood he shed with his own hand!

Truly, in this drama the words of a --"The greatest griefs are
those we cause ourselves"--explains the absolute despair of Oedipus and his
"madness" that "[L]eaped on" him and made him punish himself.  In Stophe 2,
he explains why he blinds himself,

How could I bear to
see

When all my sight was horror everywhere? 

Thus, Oedipus blinds himself in order to punish himself, and to prevent himself from
ever seeingand his children against whom he has sinned.  That is, since he has been
metaphorically blind for so long, he physically blinds himself in a gesture symbolic of his
ruin. This self-punishment also demonstrates the act of justice that Oedipus places upon
himself, for he believes his suffering is deserved since in his hubris he
has been convinced that he could end the plague of Thebes.