I can rule out that the robot is conscious, because the word "conscious" has very little meaning.
To whom? To most people, it indicates having a first person perspective, which is something rather general. It seems to mean little to you because of your gerrymnadered definition of meaning.Going only be external signs, consciousness might just be some unimportant behavioural quirks.
You can redefine "conscious" to include or exclude the robot, but that doesn't change reality in any way.
The point is not to make it vacuously true that robots are conscious. The point is to use a definition of consciousness that includes it's central feature: subjectivity.
You can either ask questions about brain activity and function, or you can ask no questions at all.
Says who? I can ask and answer subjective questions of myself, like how do I feel, what can I remember, how much do I enjoy a taste. The fact that having consiousness fgives you that kind of access is central.
having a first person perspective
What does "not having a first person perspective" look like?
gerrymnadered definition of meaning
I find my definition of meaning (of statements) very natural. Do you want to offer a better one?
subjectivity
I think you use that word as equivalent to consciousness, not as a property that consciousness has.
I can ask and answer subjective questions of myself, like how do I feel, what can I remember, how much do I enjoy a taste.
All of these things have perfectly good physical representations. All of them ca...
(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!