The tragic errors that King Lear and Gloucester make in misjudging their children constitute a form of figurative blindness—a lack of insight into the true characters of those around them. Reminding the audience of this fact, the language of the play resounds with references to eyes and seeing from the very beginning. Cornwall and Regan make these images and metaphors of (failed) vision brutally literal when they blind Gloucester in 3.7. For the remainder of the play, Gloucester serves as a kind of walking reminder of the tragic errors of blindness that he and Lear have committed. Yet, Gloucester's greater insight into the character of his two sons after he is blinded reflects an irony: literal blindness ironically produces insight. Only when Gloucester is blind can he see things for what they are.
Throughout the play, characters allude to, and call upon, the gods and the heavens watching over them. As noted above, the gods and heavens suggest order and eventual justice. However, as watchers of the action of the play, the gods also become a kind of audience, and like the audience they both see the story of what is happening more completely than the individual characters on stage and can't seem to do anything to stop it.
Blindness and Insight ThemeTracker
Blindness and Insight Quotes in King Lear
To speak and purpose not."
And dizzy tis to cast one's eyes so low!
[…]
I'll look no more
Lest my brain turn and the deficient sight
Topple down headlong."
Had I your tongues and eyes, I'd use them so
That heaven's vault should crack. She's gone forever."