I know that the experience of stubbing my toe is called pain, and I know that what I'm sitting on is called a chair. But I don't know the "precise descriptions of the full gamut of atomic configurations which implement" them in either case. This is very normal.
But not much of an argument for using semantics grounded in (physical) reality. Doing so does not buy you maximum precision in absolute terms, and , what is worse, the alternative , of grounding terms for types of experience is 1st person experience, can give you more precision.
You seem to be under impression that I advocate certain methods of examining brains over others. I don't know where you got that? I do believe that everything that could be learned about a brain could be learned by zapping one set of neurons and seeing if another set fires.
You may believe that, but do you know it?
But if it's more practical for you to show the brain something purple, and ask it to rate how bitter that felt, from 1 to 5, I have no problems with it. This method, while less direct, can be more useful (especially depending on the exact questions you want to answer). The problem, as I understand, is that you believe these two methods to be radically different, when they are not.
The difference is that I accept the possibility that first person evidence could falsify 3rd person theory.
It's as if you assume something is real, just because it comes out of people's mouths.
I'm not taking 1st person to mean 3rd person reports of (someone elses) 1st person experience.
Doing so does not buy you maximum precision in absolute terms
What sort of precision are you talking about? More generally, you're repeatedly said that the concept of consciousness is very useful. I don't think I've seen that usefulness. I suspect that elaborating here is your best bet to convince me of anything. Although even if you did convince me of the usefulness of the term, that wouldn't help the "robot pain" problem much.
You may believe that, but do you know it?
That's a slightly weird question. Is it somehow different from "why ...
(This post grew out of an old conversation with Wei Dai.)
Imagine a person sitting in a room, communicating with the outside world through a terminal. Further imagine that the person knows some secret fact (e.g. that the Moon landings were a hoax), but is absolutely committed to never revealing their knowledge of it in any way.
Can you, by observing the input-output behavior of the system, distinguish it from a person who doesn't know the secret, or knows some other secret instead?
Clearly the only reasonable answer is "no, not in general".
Now imagine a person in the same situation, claiming to possess some mental skill that's hard for you to verify (e.g. visualizing four-dimensional objects in their mind's eye). Can you, by observing the input-output behavior, distinguish it from someone who is lying about having the skill, but has a good grasp of four-dimensional math otherwise?
Again, clearly, the only reasonable answer is "not in general".
Now imagine a sealed box that behaves exactly like a human, dutifully saying things like "I'm conscious", "I experience red" and so on. Moreover, you know from trustworthy sources that the box was built by scanning a human brain, and then optimizing the resulting program to use less CPU and memory (preserving the same input-output behavior). Would you be willing to trust that the box is in fact conscious, and has the same internal experiences as the human brain it was created from?
A philosopher believing in computationalism would emphatically say yes. But considering the examples above, I would say I'm not sure! Not at all!