You are not treating the identity of pain with brain states as a falsifiable hypothesis.
No, I'm treating the identity of pain with the memories thoughts and behaviors that express pain, as unfalsifiable. In other words, I loosely define pain "the thing that makes you say ouch". That's how definitions work - the theory that the thing I'm sitting on is a chair is also unfalsifiable. At that point the identity of pain with brain states is in principle falsifiable, you just induce the same state in two brains and observe only one saying ouch. Obviously, there are various difficulties with that exact scheme, it's just a general sketch of how causality can be falsified.
There are uncontentious examples of multiply realisable things.
I don't recall suggesting that something isn't MR. I don't know why you think that MR is a problem for me. Like I said, there are multiple realizations of pain the same way that there are multiple realizations of chair.
No, I'm treating the identity of pain with the memories thoughts and behaviors that express pain, as unfalsifiable.
Is that supposed to be a novel theory, or a dictionary definition?
I don't recall suggesting that something isn't MR
Your suggesting pain can't be instantiated in robots..
(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!