Delmar O'Donnell: But how'd he know about the treasure?
Ulysses Everett McGill: The blind are reputed to possess sensitivities compensating for their lack of sight, even to the point of developing paranormal psychic powers. Now, clearly seeing into the future would fall neatly into that category; it's not so surprising then that an organism deprived of its earthly vision...
Pete: He said we wouldn't get it. He said we wouldn't get the treasure we seek on account of our obstacles...
Ulysses Everett McGill: Well what the hell does he know? He's just an ignorant old man.

— O Brother, Where Art Thou?

"I think he sees more than he lets on."
—Gerrard Capashen, flavor text on Blind Seer