In message <199901092316.QAA25756@northlink.com>, John Dale
<johnd@smtp.northlink.com> writes
> Robin, if consciousness is "not there", then what is the
>difference to you between being asleep and being awake?
>Typically we talk about "states of consciousness". Various
>sciences and traditional teachings point to two or more
>basic states, "states" here referring to degrees of
>intensity or depth.
>
> I need to read books like Dennett's *Consciousness
>Explained*, but it puzzles me how anyone could think that
>consciousness simply doesn't exist at all in some sense of
>that word and that it does not have variations of
>intensity.
"In some sense of that word" -- precisely. The difference between being awake and being asleep can be characterised in entirely physiological/behavioural terms. There's no need to refer to the subjective, experiential aspect. So when we use "conscious" to mean someone's not asleep, it has a clear meaning.
But that's not the meaning I was talking about. Imagine a robot, or android, like in Blade Runner but even better, absolutely indistinguishable from a natural-born human. Now, some would disagree, but most seem to find it conceivable that this android would *not* be conscious. It would, to all appearances, be awake at times and asleep at other times, but at no time would it have subjective experiences -- there is nothing that it is like to be that android. In the philosophical literature, they talk about zombies rather than androids, but the principle's the same.
"Consciousness", in the sense I was discussing, is what we have that distinguishes us from such a machine. And what I'm saying is that, in purely objective terms, there is no such thing. (And I added, for the sake of balance, that in equally strict terms there is no such thing as matter, either.)
For the other side of the argument, see here: http://www.faichney.org/synthesis/candm/ You Can't Argue with a Zombie by Jaron Lanier is an entertaining and effective demolition of the position of such as Daniel Dennett on zombies.
I've put the Synthesis website on ice, and am now working on a site that's more tightly focussed on the issue of machine consciousness. When it's worth looking at, I'll let the people here know.
-- Robin