Mary’s room is a classic philosophical thought experiment about consciousness. The Wikipedia article on what’s called the knowledge argument quotes Frank Jackson, the originator of the argument, as follows:
Mary is a brilliant scientist who is, for whatever reason, forced to investigate the world from a black and white room via a black and white television monitor. She specializes in the neurophysiology of vision and acquires, let us suppose, all the physical information there is to obtain about what goes on when we see ripe tomatoes, or the sky, and use terms like ‘red’, ‘blue’, and so on. She discovers, for example, just which wavelength combinations from the sky stimulate the retina, and exactly how this produces via the central nervous system the contraction of the vocal cords and expulsion of air from the lungs that results in the uttering of the sentence ‘The sky is blue’. […] What will happen when Mary is released from her black and white room or is given a color television monitor? Will she learn anything or not?
The takeaway idea from this thought experiment is supposed to be that, since Mary knows “all the physical information there is to obtain” about seeing color, what she learns when having her first actual sensory experience of color must be non-physical.
But this assumes that it is possible for Mary to actually know everything physical about seeing color, without actually ever seeing color. It seems clear she does get new knowledge when she leaves the room, the knowledge of what it’s like to actually experience color. The question is what the nature of that new knowledge is. Like so many of these types of exercises, the premise essentially assumes the conclusion, that raw subjective experience isn’t physical. But if the raw experience actually is physical, then the premise is a contradiction, positing that she has all the information, then going on to describe what information she doesn’t have.
But the question I have is, why does this premise, that experience is not physical, seem compelling to so many people? (At a philosophical level. I understand why so many people find it emotionally compelling.)
One of the chief features that separate humans from other animals is the degree to which we can think symbolically. Language is the most common example of this ability. Other animals issue sounds which mean something to those around them, such as a monkey who issues a certain screech for a snake, and a different screech for a flying predator. But only humans appear able to manipulate the sounds in complex sentences and frameworks, particularly with hierarchical and recursive levels of complexity.
When we use language, we utter a sound that is a symbol for something else. That something else might be another symbol acting as another placeholder for collections of more primitive symbols. But eventually, if we follow through the hierarchy of symbols, the most primitive ones we can find will represent sensory perceptions, emotions, or actions, in other words, raw conscious experience.
Now, you might argue that some words refer to objects, such as dogs. But dogs are themselves a composite sensory experience. When I say the word “dog” to you, it evokes certain imagery. But the dog concept generally denotes a certain type of animal with a certain type of body plan. The imagery has colors, textures, shapes, sounds, and smells, in other words, more primitive sensory experiences.
We might also talk about the altered consciousness of meditative states some people experience. But if you read descriptions of those states, they’re always either using a new word to label that state, or attempting to describe it in terms of the other primitives we’re all familiar with.
So, all language ultimately reduces to these primitive aspects of conscious experience: sensory perception, primal emotions, motor action, and perhaps meditative states. Once we reach this point however, language ends. While we can come up with words as stand-ins for these primitives, we can’t further describe them.
For example, consider trying to describe the color yellow to someone who had been born blind. You can’t. The best you can do is attempt to relate it into terms the blind person might understand, such as the feel of sunshine, the touch and smell of bananas, etc. But you can’t describe the raw experience of yellow to them. It’s ineffable.
But does this ineffability, this inability to subjectively reduce the raw experience further, mean anything about the reality of such an experience? What about this ineffability might lead us to conclude it involves something other than physics?
It’s worth noting that just because these experiences can’t be subjectively reduced, it doesn’t mean that the neural correlates can’t be objectively reduced. For example, we know the experience of yellow begins with photons with wavelengths of between 575 and 585 nanometers striking our retina, exciting a mixture of red sensitive and green sensitive light cone receptors and causing a cascade of electrochemical signals up the optic nerve to the thalamus and occipital lobe, somewhere producing what will eventually be communicated as yellow to the other brain centers.
Of course, we are far from a full accounting of the neuroscience here. And many seem always ready to seize on the remaining gaps as an opportunity to wedge in mystical or magical notions. But every year, those gaps close a little more. Taking solace in them seems like an ever eroding stance.
A common argument is that we don’t know why these experiences exist. Why can’t the brain go about its business without them? This seems to assume that raw experience is superfluous to what the brain does, and perhaps that superfluousness means that it’s outside of the causal framework we call “physics”, an epiphenomenon.
But as I’ve noted before, the very fact that we can discuss primal experiences and apply symbolic labels to them means that they’re not outside of that causal framework. It takes extreme logical contortions to avoid concluding they don’t influence at least the language centers of our brain.
So then, what explains experience? As I’ve noted before, I think to have any hope of answering that question, we have to be willing to ask what experience actually is. It seems like there are many possible answers, but the one I like best is grounded in the evolutionary reason for brains, to make movement decisions. Experience is communication. But communication from what to what?
I think the answer is: communication from the perception centers and emotion centers of the brain to the movement planning centers. This communication provides information that is crucial for the movement planning centers to do their job. What we call “experience” or “feeling” is the raw substance of that communication. This communication includes sensory perceptions (including a sense of self) and emotional reactions. Remove it, and it’s difficult to see how movement decisions can happen.
Of course, this remains a speculative explanation. Any explanation of experience will be at this point. The question is, does speculation of this type, built on physical functionality we already know has to exist in the brain, involve fewer assumptions than speculation about non-physical phenomena?
It’s often said that subjective experience can’t be explained physically. My question is, what am I missing? What about experience causes people to say this? What specific attributes are outside the purview of any such explanation?