Please read my post before commenting.
I’ve heard the elbow thing and the “what do you see behind you” thing a hundred times.
My thought process is that the optic nerve is essentially an HDMI cable. Whether it is connected to a computer that is turned off (a closed eye, if you will) or just completely disconnected (suppose you are missing an eye or something), the signal it sends to the monitor is the same: nothing.
The “monitor”, the visual cortex, as far as I understand, just constantly processes what the optic nerve sends. So if blind people don’t lack a visual cortex, and the signal that cortex receives from the optic nerve is identical to that of a regular person seeing zero light (assume closing your eyes means 0 light, disregarding light seeping through eyelids and whatnot), how can you say that blind people see nothing while we see black?
In: Biology
Close your eyes and imagine a glowing red ball about the size of a tennis ball. Got it? Ok good.
Now using just your imagination start to move the ball to the right side of your vision or your face. Keep going so it’s perpendicular with your right ear.
Eyes closed this is imagination only.
Keep going so it’s directly behind you. It’s something your brain has never encountered. You have never done it. Your brain will try to go into third person view to permit you seeing it behind you. Your brain can understand a glowing ball behind you if it’s a third person perspective though. You can’t imagine a first person perspective
The ball behind your head now isn’t red or black.
Do see black when you look through the back of your head while facing forward outside the range of what you can see? No. It is just not there. You can do this one eye at a time too when you close only one and not in bright light your brain will not even register the black from the closed one. Do it for both, mix, and shake for a blindman’s darkness.
Imagine you’re standing in an odorless room. You don’t smell anything. You don’t smell “black”.
Some fish (and other animals) can sense electric fields. How is it that you just don’t sense electric fields at all rather than sensing zero electric field?
I’m losing my eyesight thanks to not taking care of my diabetes. I’ve posted before on another blind related question.
You would think everything slowly starts to get darker and then blackness. That’s not it. Everything is kind of getting misty. If you’ve watched The Mist, that’s kind of like what’s happening to me but not exactly. (Smaller monsters, goddamn spiders everywhere!) But that’s how it is for me, just slowly sinking into a whitish, misty kinda deal.
> The “monitor”, the visual cortex, as far as I understand, just constantly processes what the optic nerve sends. So if blind people don’t lack a visual cortex, and the signal that cortex receives from the optic nerve is identical to that of a regular person seeing zero light
Some blind people can have a non-functional or mal-functioning visual cortex. Some people can see but not know that they can see cause their brain is ignoring or not processing the signals. If you ask someone like this what do they see in front of them, they say they can’t see. But if you flash a sudden light they might flinch. Or if an object is flying at them they will subconsciously avoid it.
Sometimes the optic nerve is not working. So the signal the cortex is receiving is *not* identical to a regular person with closed eyes. Having no signal is not the same as having signal of black.
>the signal it sends to the monitor is the same: nothing.
Using your HDMI cable qnalogy, imagine the monitor is actively receiving and displaying the signal of black versus having no signal. Blind is no signal. Seeing with eyes closed is monitor with signal to show black.
How would they know? How would anyone know?
When my dad became blind I asked him what he could see – dark, light or anything at all. He told me that there is bright white light all the time. No shadows or any other colors. Just pure white light
You know how you aren’t able to sense the presence of extra dimensional beings? That’s how blind people don’t see black.
To see black you have to understand what black is. For someone born blind the concept of colour is non-existent.
Some partially blind people see light and dark but even then how so they explain what that is conceptually. Is dark black? Who knows? They can’t explain it because they don’t have a source to reference their explanation against.
It is part of the discussion about colour blindness. You might see red and green. I however don’t. I see shades of something that I refer to as red and green because everyone else calls it that. Sometimes I mix them up. Then it is discovered that I don’t differentiate between two light frequencies that are markedly different. That is Red/Green colour-blindness.
As a result I still don’t know the difference between red and green just as a blind person does not know the difference between nothing and black.
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