Evidence of Consciousness Surviving the Body One of the mistakes some people make in defining consciousness is that they want to define it by looking inward, i.e., our subjective experience. However, how can I say someone else is conscious based on this kind of subjective experience? After all, I'm only aware of my own consciousness, of my own inner experiences. It's important to bring in a Wittgensteinian idea to get clear on this mistake, i.e., that words get their meaning in public settings, not by pointing to an inner thing (beetle in a box problem). However, this doesn't mean that there isn't something inner going on, it just means that meanings don't attach to inner subjective objects. But concepts do reflect inner thoughts, and this is different from saying that concepts don't derive meaning from our inner world of thinking.
Wittgenstein doesn't deny our inner subjective life. One can think of it this way, when I use the word cup, meaning isn't derived from the object (the referent), although the object can be used to help us understand how to use the word in linguistic social settings. So, it's not as though the object has no role in our language, so we want to be careful to not eliminate our talk about the object. The tendency is for us to associate the meaning of a concept with the object, this is where we go wrong. It's a difficult habit to break, because it's so pervasive.
The point of the above remarks is to say that our inner life isn't some illusion, as some would suggest. There are those materialists who believe that if it's not an illusion (the illusion being the sense of self that seems to be non-material or metaphysical), then we can't explain it in terms of the material. Their point is that that sense of self can be explained in material terms, so they write off the metaphysical awareness by saying it's an illusion.
The first mistake is to call our inner awareness an illusion. Of course we can be mistaken in thinking it reflects some metaphysical existence (although I don't think it's a mistake based on the testimonial evidence of NDEs). Illusions only make sense against the backdrop of the real, of reality. So illusions give the appearance of something real. In other words, they cover reality with a blanket that hides the real. For example, the illusion of seeing a women cut in half by a magician. We can only say it's an illusion because we know that the women isn't being cut in half, although it appears so. So, we need to ask ourselves, what is the illusion of? Am I not having these inner experiences? Who is having the illusion, if not me? If I were to uncover reality would I find that someone else is having the real experience of self? Supposedly, if we were to uncover reality in this situation, we would find mechanistic explanations of consciousness or self. So, what the mechanistic or materialists want us to believe is that brain produces in us the illusion of consciousness or self. If someone is having an illusion, it presupposes a consciousness, i.e., it presupposes the real, so who is having the illusion? However, they might argue that it's not all an illusion, just the part where we disagree with them, the metaphysical part. I think part of the problem is the misuse of the word illusion. Just as the word hallucination is misused in describing NDEs. At the very least the argument that consciousness or the self is an illusion is spurious.
Another mistake is in defining consciousness as some thing in the brain, i.e., you're not going to be able to point to some process and say, "This is consciousness." Of course you can get around this by saying that certain brain processes produce consciousness. I can't make any sense out of material processes producing the feeling I get from seeing a beautiful sunset.
That said, I wouldn't use any of these arguments to argue against the materialist worldview. I'd use my inductive argument already given in this thread, it's much stronger.
Anyway, just some thoughts.