He is blind, although it is not always obvious.
This was particularly the case for me since I saw this movie on a plane, which had been edited (the movie, not the plane).
Some of the subtle clues to demonstrate
he is blind: When he flicks the lighter open and flicks it, he moves his hand over the flame to prove to him it works because he's blind.
He kept clicking the iPod even though it said battery low.
If he could see, he'd realize the battery was low.
Only after clicking like crazy did he realize it was low.
He kicked the bottom stair before walking up the steps to the old folks house.
He didn't see the no trespassing sign because he was blind.
At the beginning of the movie, he shoots a hairless cat only when he hears it move.
It is only after Eli is fired upon from the guy on the roof that Eli takes cover and fires back.
And each time someone fires on him, Eli turns in that direction and returns fire.
Eli accidentally shoots Carnegie in trying to shoot the guy running in Carnegie’s direction.
When Solara first comes to seduce Eli
she is obviously dressed for solicitation
and she says "don't worry you don't have to pay.
"
Eli replies "pay for what," since he can't see all the visual clues that Solara is giving him.
Just before he cooks the cat, Eli searches the house he's in.
While he does so, he touches the contents of a shelf in order to glean what its contents are.
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In the Bible, Eli grew gradually more blind, from partial sight up to the stage of 'his eyes were set so he could not see'.
I'm not sure that would happen over the brief duration of the film, but maybe he wasn't fully blind in the film, but had learnt brail in 'the world before' so as to better be able to read.
I agree all the things above could prove he had bad eyesight or possibly even be blind, but there are parts in the film that make me think he could see at least slightly, like when the motorcycle gang attacked the two travellers, granted he could hear them, but he looked around the rubble to better see, and then pinpointed the gangleader in the bar in town.
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From a technical point of view.
it's possible to have enough sight to shoot at moving targets as shadows on a bright background but still not be able to read at all.
Using sound to identify targets versus friendlies helps.
Eli knows when there are people there, but waits for them to declare their intentions.
Once that is established, he simply aims at the body mass.
Targets at a gun range don't need faces or hair styles to get shot in the chest.
If you just knew the order of the books in the bible, you could learn braille by just learning the letters of the names of the books.
I bet you could get most of the braille alphabet from just the names of the books, which are on every page of each book if you already know the names and order of books.
Thirty years is a long time.
Helen Keller was reading braille at a younger age than that and she was born blind.
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He is not totally blind, for the reason that when they go back in the old cannibal couple's house and ask for weapons Eli looks at the window to check the surroundings.
This takes place around minute 77.
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When he was leaving the house at the beginning, after eating the cat and feeding the mouse, we see his eyes.
Then at the end his eyes are obviously white and blind.
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He was partially blind, not blind.
Due to the 'flash'.
There are hints that he had trouble seeing, the use of the glasses throughout shows the light hurt his eyes.
But if you watch again with the sole purpose to see if he is completely blind, the movie fails to show this.
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Eli is blind throughout the whole movie.
How he became blind is up for debate.
He is not the last living blind person; Solara's mother tells him that she was born blind.
He asks her whether it happened after or during the war, which may give the reason for his blindness.
He walks for thirty years because that's how long it takes for him to remember the entire Bible and to understand its message, which he tells Solara toward the end.
If you notice, throughout the movie, he uses his senses a lot except for the sense of sight.
Everyone wears glasses because of the glare, not just him.
He tells Solara that the message is to treat others better than yourself.
This message rings loud and true at the end when the villain tries to get Solara's mother to read the book.
She tells him that she's forgotten how, which is not true.
He treated her so badly, why should she do this for him?
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In the Movie " The Book of Eli " we discover at the end that the Bible Eli has been carrying the entire movie is written in Braille.  Does this imply that he is blind (and has been living completely "by faith" his entire life)  or is the punchline of the movie that he is the simply the last living man on Earth who can read Braille?
Is Eli blind, or can he just read braille?
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<the-book-of-eli>
scifi.stackexchange.com/questions/30799
scifi.stackexchange.com/users/2378/Timothy Baldridge
Eli is considered to be blind, although it is not always obvious. There are hints that Eli had trouble seeing, the use of the glasses throughout shows the light hurt his eyes. It seems that he is not totally blind, as when they go to the old cannibal couple's house and ask for weapons, Eli looks at the window to check the surroundings. Also, throughout the movie, he uses his senses a lot except for the sense of sight. Eli was blind before the war but after finding the Bible he regained his sight upon hearing God’s voice. This is why Eli could read Braille because he had had to learn it before regaining his sight.
Eli was blind, or partially blind, before the war but after finding the Bible he regained his sight upon hearing God’s voice. Eli could read Braille because he had had to learn it before regaining his sight.