Even if its individual membrane-bound neurons are micro-pixels of experience, there’s no phenomenally unified subject.
It would be meaningless to talk about a phenomenally unified subject there, since it can’t describe its perception to anyone (it can’t talk to us) and we can’t talk to it either. On top of that, it doesn’t implement the right kind of a state machine (it’s not a coherent entity of the sort that we’d call it something-that-has-a-unified-mental-state).
You remark that “A physical object implementing the state-machine-which-is-us and being in a certain state is what we mean by having a unified mental state.” You can stipulatively define a unified mental state in this way. But this definition is not what I (or most people) mean by “unified mental state”. Science doesn’t currently know why we aren’t (at most) just 86 billion membrane-bound pixels of experience.
A physical object implementing the state-machine-which-is-us and being in a certain state is what we mean by having a unified mental state.
Seemingly, we can ask but why does that feel like something instead of only individual microqualia feeling like something but that’s a question that doesn’t appreciate that there is an identity there, much like thinking that it’s conceptually possible that there were hand-shape-arranged fingers but no hand.
It would be meaningless to talk about a phenomenally unified subject there, since it can’t describe its perception to anyone (it can’t talk to us) and we can’t talk to it either. On top of that, it doesn’t implement the right kind of a state machine (it’s not a coherent entity of the sort that we’d call it something-that-has-a-unified-mental-state).
You remark that “A physical object implementing the state-machine-which-is-us and being in a certain state is what we mean by having a unified mental state.” You can stipulatively define a unified mental state in this way. But this definition is not what I (or most people) mean by “unified mental state”. Science doesn’t currently know why we aren’t (at most) just 86 billion membrane-bound pixels of experience.
There is nothing else to be meant by that—if someone means something else by that, then it doesn’t exist.