I won't have much time for posting for a while, but it would not be fair not to comment on your excellent post. As I usually do when I'm out of time, I'll pick one paragraph which embodies the essence of my argument:
" This is a problem for the philosophers of language. It is unsolved, and I won't pretend to have developed an answer. What I will say is that words do not have meaning of themselves since they are symbols. [...] Hence, trying to understand how we learn a first language is not the same as saying that words only have meaning unless they refer to something. Every word used has a reference, otherwise dictionaries would be in trouble when they failed to define a word. "
Well, just like you I don't have a solution for the many puzzling issues of analytic philosophy (is that the right name?). However, it's clear to me that 'consciousness' happens to be a problem for analytic philosophers, not for scientists. Let me try and explain why.
In all honesty, I have no idea what you are talking about when you use the word 'consciousness'. I have something of a foggy notion, but it's really hard to get the exact meaning you impart on the word. I use the word myself, but from your usage it's clear that we are not talking about the same thing. Why do I think so? Because you use the word 'consciousness' to make statements which to me are either false or meaningless, and I use the word 'consciousness' to make statements which to you are either false or meaningless. Now there are two possibilities: either one of us doesn't understand what the word really means, or the word refers to a concept that does not exist in reality.
The first possibiliy is, I suppose, trivial and does not need further explanations. The second possibility, however, is extremely interesting from my perspective, and I'll tell you why: if two people disagree about a concept that does not exist in reality, it's possible for both of them to be right! For instance, if I say 'raw fish tastes great' and you say 'raw fish tastes awful', we can both be right to the extent that raw fish tastes differently to each of us. 'Taste' is, after all, not a property of the fish itself, but the property of our experience of eating it. There's nothing wrong or paradoxical about the fact that some aspects of our experience of fish are not consistent with other people's experience. That is why we call them 'subjective'.
Now the problem with consciousness, the reason I object to scientific research on the subject, is not only that 'consciousness' is, like 'taste', a purely subjective phenomenom. If it were a subjective phenomenom we could at least find its correlates in the physical world, just like we find that our subjective taste of raw fish is always associated with the physical act of eating raw fish. We would never agree on whether it tastes this way or that way, but at least we would know what we are talking about.
The problem with 'consciousness', the reason the subject is not a legitimate one for science, is that it doesn't exist! There's nothing in the world which we can point to and say, "look, there is the source of all my conscious experiences", as we can point to fish. And there's nothing in any particular subjective experience that we can analyze and say, "oh, these kinds of experience are always associated with my feeling of being conscious", as we so easily associate the experience of munching fish with the experience of feeling its taste.
I doubt this will make my point easier to understand. In essence 'consciousness' is a word that stands for something which is not real. To seek explanations for consciousness is not unlike seeking explanations for how the number 57 works or which part of our brain is responsible for calculating baseball scores. At the root of the imbroglio is our enormous tendency to give more meaning to abstract concepts than they can possibly have. The bewitchment of thought by language, as Wittgenstein put it.
It's not science that will take us out of those situations; only analytic philosophers can help us by showing how our language confuses our understanding of the world and ourselves.
Well, so much for philosophizing, now the real world is eagerly waiting for me.