Qualia: Mary’s Room
Please familiarize yourself with the following: Mary’s Room
The first objection to that thought experiment is that it postulates an entity with complete knowledge of an event, which logically requires complete knowledge of the entire universe. And that’s impossible from within the universe. ‘Complete scientific knowledge’ requires strong omniscience, which I am reasonably certain human beings do not have.
But let’s be generous, and presume that something far weaker was meant. What if Mary merely knew everything that the scientific method could ever reveal to us about human neurophysiology and the processes of visual perception?
Then it would be absurd to speculate what such vast knowledge would not let someone know, since it would extend far beyond our current understandings of those things. How would you know that such knowledge wouldn’t give Mary foreknowledge of color? Hmmm?
Let’s be even more generous, and limit Mary’s knowledge to what can be plausibly extrapolated from our current knowledge. Doesn’t Mary learn something new about color then?
Stimulation of the optic nerve is perceived as light and color. As are certain kinds of stimulation of the parts of the brain involved in processing vision. Presumably sufficiently precise stimulation of the parts of the brain involved with memory retrieval would result in ‘remembering’ visual experiences as well. It’s possible that memory involves the use of what are effectively pointer variables, so the ‘experience’ wouldn’t be part of the memory itself in that case, but it would involve a reference to the brain modules involved with vision.
If Mary’s knowledge were extensive enough, she could completely lack the parts of the brain specialized to deal with vision, but emulate them in non-specialized parts of her brain sufficiently flexible as to permit Turing-complete processing. Or with an electronic computer. Or by writing things on scraps of paper and shuffling them around. You get the idea.
The resulting output, when fed into the right places in Mary’s brain, would produce exactly the same result that beaming the right kinds of light into her eyes normally would.
Hell, if all she wants to do is learn about color, she could just push gently on her eyeballs. The resulting nervous stimulation from the pressure would generate all sorts of colored patterns.