By Austin Garrido
The so-called “experience” of a phenomena is indistinguishable from the processing of the information contained in that phenomenal experience, and it is not one-way knowable.
I propose that the qualia of "experiencing" the phenomenon is inseparable from the pattern of physical changes that occur in the system that is experiencing. Whatever qualia exist, exist embodied in whatever physical changes are occurring. If the neural pathways activated by experiencing a phenomena were removed, most would agree that any existence of a conscious mind experiencing that phenomenon would also disappear. Since the experience of the qualia is intrinsically tied to whatever system (in this case the "neuronal firings”) that is experiencing it, I propose that any claim that distinguishes them is a product of the inherent imprecision of our (and any) spoken language.
There is a classic thought experiment involving a woman, Mary, who knows all physical facts, with a specialty in the neural basis of vision, color, and perception. Mary is aware of all physical reactions, down to a sub-atomic level that occur when a biological brain perceives the color “red”. Mary, herself, however has never seen red- she lives in a hypothetical house where there is nothing emitting light in the red part of the spectrum. We assume that she maintains the ability to see red, but that ability has never manifested itself. The question remains that, whether upon going outside her house and actually experiencing a red rose, Mary gains any new information. Philosophers like Thomas Nagle and Jackson are likely to say that she does. If she does, then knowing/experiencing something must be non-physical, since even complete knowledge of the physical reactions to an experience is still consciously different than perceiving the stimulus externally.
Pete Mandak initially summarizes the “subjective experience is one-way knowable” argument as (K):
“(K): For all types of phenomenal character, in order to know what it is like to have a conscious experience with a phenomenal character of a type, one must have, at that or some prior time, a conscious experience with a phenomenal character of the same type.”
He goes on,
“However, even fans of Nagel and Jackson are likely to reject (K) on the grounds that there are many types of phenomenal characters for which (K) is highly implausible. Suppose that there was some shade of gray or some polygon that Mary had never seen before. Few philosophers are likely to suppose that Mary would be surprised on seeing a 65.5% gray or a 17-sided polygon for the first time. Perhaps, then, the idea behind subjectivity considerations is better put by modifying (K) by replacing “the same” with “a relevantly similar” and replacing “all” with "at least one," resulting in the following:
(K+): For at least one type of phenomenal character, in order to know what it is
like to have a conscious experience with a phenomenal character of a type, one
must have, at that or some prior time, a conscious experience with a phenomenal
character of a relevantly similar type. “
If Mary indeed knows all physical facts, then, in effect, she is running a point by point simulation of the involved physical processes in perceiving that physical phenomenon, by the very fact the location is known at each successive iterance of all of the particles involved in the perception of the color red.[1]
The act of remembering a phenomenal experience is, according to argument K+, impossible for someone who has never consciously experienced that particular phenomena or a relevantly similar state (such as Mary having seen, at some point, different shade of red from the rose), and is therefore intrinsically tied to the state of externally perceiving said phenomena (argument K+). Indeed, it is difficult to separate the two. They are highly interconnected and I propose that when the experience of seeing red is remembered, the actual system that is being recreated is the neural state of “perceiving” the color. As memories fade, the ability to recreate those past neural states fails, part by part, forming a fuzzier and fuzzier recreation of what the experience was in the first place.
What is a memory? A memory is a particular neural state characterized by experiencing a phenomenal experience. In fact, the brain scans show remarkably similar brain activity for physically doing an activity compared to visualizing doing that same activity introspectively [1].
Neural signals in neocortical layers are not only feed forward, but also feedback, and some combination thereof results in conscious thought. However, if the “feedback” part of that system is removed, then no conscious thought could take place, as the time it takes a neural signal to reach the top of a cortical column is negligible. A thought arises either through introspection, or else by external stimulation. It’s analogous to thinking of a politician because one was thinking of politics, versus physically seeing that politician.
Importantly, the difference between introspection and external stimulation are inseparable to neural network, as introspection involves using the output of one neural structure as input into another iteration, whereupon more pathways are activated, and external stimulation involves inputting data into that neural system with the only difference being that it happens not to come from some other thought process. A neural architecture that only goes one direction would be exhausted very rapidly. In experiments with anesthetized animals [2], there is brain response from stimuli, but only feed-forward that lacks feedback from higher to lower levels. So while a stimulus was still being experienced, consciousness was not achieved because of the lack of feedback in the neural structures, pointing to a neural structure that produces consciousness.
Mary, in her infinite physical wisdom, would certainly know of whatever physical neural state was analogous to “experiencing” the color red. Since the act of remembering a phenomenon is intrinsically connected to (and in practice, identical to) experiencing that phenomenon, then recreating the neural state of experiencing a phenomena, as described in Mary’s “simulation” is identical to externally perceiving red, which is analogous to externally perceiving the color red, and Mary would not gain any new and non-physical information by physically experiencing the color red.
Finally, evidence found in red-green color blind synthesithetics [3] were tested to see what colors they saw with certain stimulus. They reported that certain stimuli produced colors that they had never experienced in real life, and indeed were so bizarre to them that they called them “martian colors”. We can guess what those “martian colors” are! They are their missing greens and blues, for which their brain’s already had architectures for perceiving, which had never been activated externally. It is probable that the same thing would happen to Mary, experiencing the color red as the synthesithetics do the reds and blues.
The important thing is that, despite never actually physically experiencing a phenomenon, the experience was still consciously achieved through a different means, rendering argument K+ assertion of subjectivity being one-way knowable invalid.
[1]
[2] Lamme et al. (1998)
[3] Ramachandran, V.S.; Edward M. Hubbard. (April 14, 2003). “More Common Questions About Synthesisia” Scientific American.
[1] Before I proceed, let me examine a problem that may arise carrying out the thought experiment in this universe- very interestingly, Mary’s “simulation” of perceiving the color red involves her to having explicit knowledge of each involved particles’ exact position at each incremental step of the process of the experiencing a phenomena. While being physically impossible in the universe know both a particle’s exact position and momentum according to Heisenberg’s uncertainty principal, it is non-trivial in this case, as the physical system representing “Mary” can be of infinite size, and can accordingly calculate all the involved particles quantum positions within the universe, which is finite in size.
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