A recent speech given by Daniel Dennett for TED illustrates the now common infiltration of scientific presuppositions into what often gets identified as the philosophical enterprise, and although this tendency to render the scientific method as metaphysically true can be seen most obviously in the neo-atheist's (among which Dennett counts himself) arguments against religion, in this case Dennett commits the same error of method in regard to cognitive philosophy. I have not read Consciousness Explained and so cannot comment on the rigor of that work, but I think it possible to see in Dennett's presentation for TED the starting point of his philosophical approach to the "problem" of consciousness. He says:
Dennett's description indicates a thoroughly materialistic metaphysic which considers the truly real aspects of the universe to be quarks, atoms, cells, electromagnetic forces, and so on. I have directly argued against this view elsewhere, but there's a rather obvious problem in talking about consciousness in this way which should be immediately evident to anyone with any philosophical acumen whatsoever. Even without any phenomenological training one might see the peculiarity of trying to explain consciousness by referring to things which can only be accessed through that same consciousness; or to put it another way, the problem of explaining consciousness by the objects of consciousness which can never be spoken of outside the domain of consciousness. Quarks and neurons can only be conceived of after one has adjusted their consciousness so as to conceive of the universe through mathematical physics; consciousness rather obviously precedes any of its objects in the act of knowing, whether they are scientific entities or common artifacts. Objecting to the explanation of a phenomena in terms of things which can only be made known by that phenomenon does not mean that one must fall back on the supernatural because no rational alternative can be found, and Dennett's method can only be called natural in the same sense as Locke's theory of perception: Locke attempted to explain the mind as a blank sheet of paper upon which experience writes, but in doing this he commits the "naturalistic fallacy"--he attempts to explain something by something else, though he -- more than Dennett -- understood this method as an analogy. Here we see the real problem: if we wish to explain something and understand it in itself we cannot simply substitute other things which admit to simpler explanation and declare our work done, and this basic error of substitution only gets aggravated when we try to explain something which reveals something else by the thing revealed.
If Dennett begins to study consciousness by the things to which consciousness might be directed such as the bodies cellular activity, he has already run past the phenomena of consciousness. Really, it makes no difference whether he attempts to explain consciousness though cellular activity, by referring to a sheet of paper, or by referring to anything else which he might be conscious of; for Dennett has ignored how we become conscious of these things in the first place.
The difficulty of discussing consciousness lies in the fact that we do not usually become conscious of consciousness, from which follows that philosophical language which talks about the things at which we can direct our conscious will have to be revamped or abandoned if it intends to make the mind thematic. Phenomenology takes up this project, and in Husserl, Heidegger, Merleu-Ponty, and others we see attempts at this. A good bit of conflict can be found, especially between Husserl and Heidegger, but the important thing about phenomenologists is that they realize the problem. Dennett would do well to engage with these philosophers instead of simply repeating the prejudices of cognitive science and christening it "philosophy."
What you are, what I am, is approximately 100 trillion little cellular robots; that's what we're made of, no other ingredients at all, we're just made of cells... Not a single one of those cells are conscious, not a single one knows who you are or cares. Somehow we have to explain how when you put together teams, armies, battalions of hundreds of millions of little robotic unconscious cells, not so different, really, from a bacterium, each one of them, the result is this [Dennet points to an an illustration of the mind], I mean just look at it: the content, there's colors, there's ideas, there's memories, there's history, and somehow all that content of consciousness is accomplished by the busy activity of those hordes of neurons. Many people just think it isn't possible, at all. They think: "No, there can't be any sort of naturalistic explanation of consciousness."
Dennett's description indicates a thoroughly materialistic metaphysic which considers the truly real aspects of the universe to be quarks, atoms, cells, electromagnetic forces, and so on. I have directly argued against this view elsewhere, but there's a rather obvious problem in talking about consciousness in this way which should be immediately evident to anyone with any philosophical acumen whatsoever. Even without any phenomenological training one might see the peculiarity of trying to explain consciousness by referring to things which can only be accessed through that same consciousness; or to put it another way, the problem of explaining consciousness by the objects of consciousness which can never be spoken of outside the domain of consciousness. Quarks and neurons can only be conceived of after one has adjusted their consciousness so as to conceive of the universe through mathematical physics; consciousness rather obviously precedes any of its objects in the act of knowing, whether they are scientific entities or common artifacts. Objecting to the explanation of a phenomena in terms of things which can only be made known by that phenomenon does not mean that one must fall back on the supernatural because no rational alternative can be found, and Dennett's method can only be called natural in the same sense as Locke's theory of perception: Locke attempted to explain the mind as a blank sheet of paper upon which experience writes, but in doing this he commits the "naturalistic fallacy"--he attempts to explain something by something else, though he -- more than Dennett -- understood this method as an analogy. Here we see the real problem: if we wish to explain something and understand it in itself we cannot simply substitute other things which admit to simpler explanation and declare our work done, and this basic error of substitution only gets aggravated when we try to explain something which reveals something else by the thing revealed.
If Dennett begins to study consciousness by the things to which consciousness might be directed such as the bodies cellular activity, he has already run past the phenomena of consciousness. Really, it makes no difference whether he attempts to explain consciousness though cellular activity, by referring to a sheet of paper, or by referring to anything else which he might be conscious of; for Dennett has ignored how we become conscious of these things in the first place.
The difficulty of discussing consciousness lies in the fact that we do not usually become conscious of consciousness, from which follows that philosophical language which talks about the things at which we can direct our conscious will have to be revamped or abandoned if it intends to make the mind thematic. Phenomenology takes up this project, and in Husserl, Heidegger, Merleu-Ponty, and others we see attempts at this. A good bit of conflict can be found, especially between Husserl and Heidegger, but the important thing about phenomenologists is that they realize the problem. Dennett would do well to engage with these philosophers instead of simply repeating the prejudices of cognitive science and christening it "philosophy."