So, presumably there are elements out there which correspond to, and are causally responsible for, elements in here where the perceiving goes on. So in that sense, it seems to me that the only kind of model of the external world that I can have has to be based upon a kind of isomorphism, hmm? An isomorphism. When I look at your face, I assume that corresponding to the different qualia I have about different parts of your face there are things out there. But on the other hand when I think of your face as having a certain colour, and so on, that I think is all projection. What I'm really doing is: I'm taking things that are going on in my consciousness and I'm fleshing out this abstract structure in such a way, as it were to make something real out of it. And in abstract physics, in a sense, one goes on with the abstract structure to greater and greater levels of abstractness, but of course one's capacity to flesh it out simply gives out completely. One's at a loss to picture what's going on when one is talking about projection operators in Hilbert Space or what have you. But in fact, as I say, I think our only knowledge of the physical world is abstract.

But now, the physical world, reality, can't be abstract. It can't be mathematics, the mathematics is just a description. So what we have to suppose here is that the physical world is fully concrete, I mean it is fleshed out. Corresponding to the abstract mathematical structure that we would have in a correct physical theory, there is a concrete physical structure and that physical structure is fleshed out, it has an inner intrinsic nature. The point is that we can't know what that nature is simply on the basis of perception, for the reasons I've given: that we only know it by way of an isomorphism. Similar to the kind of isomorphism that I referred to in my talk: that you have for example, between the pits on the CD and the motions of the piano keys and the pedals when we had that brief recital at the beginning.

Now, the next stage, and this is what I owe to Russell, though it's an idea that really goes back to Kant, and it's made more explicit in Schopenhauer. And, shorn of its specifically Kantian nature, we find it in the mathematician W.K.Clifford. But I got it from Bertrand Russell. What Russell says is, essentially, that all those qualia, all the feelings, the buzz that everybody was referring to today, that seem so difficult to fit into the physical world actually is a bit of the physical world seen in its intrinsic nature. The thought is that, in general, we can only know the physical world abstractly. We can only know its abstract structure. But if we assume that materialism is true, if we assume that our mental states are physical states, then there's going to be a corner of the physical world which we do know. Which we don't know merely abstractly, we actually know what it's like in itself. And we know what its like in itself, we know its inner nature because we are that part. That is the 'us'. That is the mind. That is the 'Cartesian Self' if you like. So, what we're really getting in our own minds is a fragmentary glimpse of the inner nature, which in the physical world in general, is systematically hidden from us. That's part of the story.

SJ: So you're almost saying that the qualia have actual physical being, physical existence?

ML: I'm saying that what we know as qualia is the intrinsic reality which in a sense gets left out in the essentially abstract description which is all that the physical sciences, that includes neurophysiology, ultimately is capable of giving.

SJ: Now, Dennett tries to remove qualia from the conversation.
ML: He does
SJ: And it seems to me that, (and this is my interpretation of Dennett, not Dennett's statement in any sense) he's doing this because the things that are named, which are what qualia usually are, are themselves the outputs of the cellular and neurophysiological processes, the neuronal processes, the neuronal subassemblies a la Greenfield this morning. And that these systems have outputs, and it's those outputs which are the nameable things which are usually accorded as qualia, but I think what Dennett is trying to do is just to say that those are simply the outputs of the systems...

ML: That's not the way I read him. In fact I reviewed his book shortly after it came out. What I take Dennett to be saying is that qualia don't exist. We believe... there are beliefs in their existence, but that's just the story we tell about ourselves. Dennett has this term heterophenomenology. And this is basically, in simple terms, heterophenomenology means the story we tell ourselves about ourselves, right? And qualia are like fictional characters in that story we tell about ourselves. That's his view.