Lately I've been posting a lot about the Coronavirus, and I found this cool thought experiment a while ago that I'd like to share with you guys. For those of you who don't know, I also find philosophy and psychological thought experiments quite interesting. The way that people think and explain things is just fascinating. So, as you can imagine, what I'm about to talk about really excites me. And I hope you find it just as interesting.
So here it is, folks!
Imagine that a genius neuroscientist named Mary was completely surrounded by only black and white things, and she has only ever seen black and white. A black and white room, books, clothes, everything. However, she is an expert in color vision and knows everything about its physics and biology. She knows about the different wavelengths of light, the three different types of cone cells in the retina, the optic nerve which carries electrical signals to the brain, and the neural signals that correspond to the millions of colors that humans can see.
But, one day, Mary's computer malfunctioned and she saw an apple in full color. For the first time, she has experienced something that she's been an expert on for years. The question is though, does she learn anything new? Is there anything about perceiving color in person that wasn't captured in all her knowledge?
The Mary's Room Thought Experiment was proposed by Frank Jackson in 1982. He argued that if Mary already knew so much about color and experiencing color still teaches her something new, then physical states such as color perception can't be described by physical facts. This is what philosophers call the Knowledge Argument, which proposes that there are nonphysical properties and knowledge that can only be learned through conscious experience. Basically, the opposite of physicalism.
The amazing thing about this experiment is if physical science can't explain color vision, then maybe it can't explain other things. Here's where it ties back into medicine...
Hypothetically, we could know every single thing about the structure and function of the human brain, particularly that of a specific person's. But, according to Frank Jackson and other philosophers, we wouldn't actually know what it's like to be that person. This is because of qualia, subjective qualities that we can't accurately describe or measure and are unique to the person experiencing them (having an itch, being in love, feeling bored, etc.) Can physical facts really explain those qualities?
So with that logic, if A.I. were able to replicate the activity of every single neuron of someone's brain, would that really mean that the A.I. was able to create a conscious state?
Years later, Frank Jackson actually re-developed his stance on his own experiment, saying that seeing the apple in full color wouldn't actually spark anything new in Mary's brain. However, philosophers are still discussing this thought experiment and there is no definitive answer.