Thursday 29 December 2016

Yearning For Consciousness--Part III

Problem of explanatory gap [Excerpts only]
The general difficulty with the problem of consciousness—unlike the very similar problem of God as we will see—is that its solution seems, at once, to be urgent and elusive. In other words, it seems that we cannot do without the concept of consciousness while, despite voluminous discussion especially in recent years, the concept continues to resist elucidation. It is this apparently ‘unsolvable’ aspect of the problem that interests me in this paper…
  To bring out the ubiquitous character of consciousness, David Chalmers (1996, xii) introduces his influential work on the conscious mind as follows:
‘I find myself absorbed in an orange sensation, and something is going on. There is something that needs explaining, even after we have explained the process of discrimination and action: there is the experience.’
Since experiences are both subjective and ubiquitous part of our lives, their occurrences call for explanation. The question arises as to what can legitimately be the form of such as explanation. Since, by the nature of the case, there is no third-person description of the phenomenon itself—that is, I cannot describe what it is for Chalmers to undergo the reported sensation, I can only describe mine—all we can do is to look for the unique conditions that are ‘objectively’ satisfied at the locus of the concerned sensation…
    So, what is it that we need to show? Here Chalmers says that it is not enough that we have explained the ‘process of discrimination and action,’ we need to explain the (qualitative, subjective) experience itself. For example, Ned Block (2007) reports interesting work by Nancy Kanwisher and colleagues who showed that there is strong correlation between face-experiences and the activation in a very specific area of the brain located at the bottom of the temporal lobe in the right hemisphere, called the fusiform face area. Block views the fusiform face area as an informationally encapsulated Fodorian module (Fodor 1983), a view that raises problems for the reportability of these experiences according to Block; I set such problems aside. Suppose there are other ‘modules’ for experience of fruits, canines, fuzzy drinks, etc. The working of these modules then would count as discriminating various stimulus items, if any, and constitute the neural actions that lead to these discriminating representations…
  Still, a description of a module in a particular state does not amount to a description of the resulting experience—what it feels like—of faces, fruits, fuzzy drinks, and the like. That is the problem raised by Chalmers: there is a crucial residue… In a later paper, Block (2009) restates Huxley’s problem by observing that ‘we have no idea why the neural basis of an experience is the neural basis of that experience rather than another experience or no experience at all.’ Block calls this the problem of explanatory gap. Let us assume that the state of the art is such that we have no clue as yet to the real ‘hard nut’ of the problem of explanatory gap: the problem of residue, that something is going on
    But suppose that, contrary to the state of the art, some detailed account of the activation of the brain does furnish a satisfactory account of the feel of what it is like to experience the computer screen. Will that count as an account of phenomenal consciousness, even if we have given up any form of dualism to agree that the brain is the seat of consciousness if anything is? Is the brain the right object to which the concept of consciousness legitimately applies? Is the brain, at that unique moment, undergoing phenomenal consciousness?
  Concerning the old issue of whether computers think, Noam Chomsky replied that legs don’t walk, people do, even if people walk with legs; similarly, computers or brains don’t think, people do. The trouble with neural correlationism is that it simply misses the grain of explanation that involves the entire organism to which the concept of consciousness typically applies. The objection is bolstered by the fact that the common notion of consciousness, which is the only notion currently at issue, does not refer to states of brains at all. It is not at all implausible to think of people correctly applying the notion of consciousness in a variety of circumstances without any knowledge about underlying brains; otherwise, most fables will not work. Of course, neuroscientists are free to use technical terms to denote the relevant unique activation states, if any, of the brain, which they believe instantiate conscious states of a subject. But that nomenclature will apply to the subject’s brain, not to the subject herself. Having noted the crucial distinction, we may as well hold on to biological correlation as the only physical basis of consciousness.
(To be continued)


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