| I feel like this is just a totally stupid question. The brain has inputs, internal processing, and outputs. The conscious experience happens within the internal processing. If you make a second copy, then that second copy will also have conscious experience, but it won't share any inputs or outputs or internal state with the first copy. If you were to duplicate your computer, would the second computer share a filesystem with the first one? No. It would have a copy of a snapshot-in-time of the first computer's filesystem, but henceforth they are different computers, each with their own internal state. You could argue that there are ways to do it which make it unclear which is the "original" computer and which is the "copy". That's fine, that doesn't matter. They both have the same history up to the branching point, and then they diverge. I don't see the problem. |
> The ‘god’s eye’ point of view taken in setting up the egalitarian metaphysics does not correspond to my ‘embedded’ point of view ‘from here’, staring out at a certain computer screen.
The vertiginous question (or Nagel's Hard Problem [2] to a degree: Why does physical brain activity produce a first-person perspective at all?) is about the subjectivity of consciousness. I see the world through my eyes, therefore there is only one "I" while there are infinitely many others.
The duplication example was something I made up to explain the concept, but to reiterate, if I could make a perfect copy of me, why would I still see the world from the first copy's eyes and not the second, if the physical structure of the brain defines "me"? What stops my consciousness from migrating from the first body to the second, or both bodies from having the same consciousness? Again, this question is meaningless when we are talking about others. It is a "why am I me" question and cannot be rephrased as "why person X is not person Y".
Obviously we don't have the capacity to replicate ourselves, but I, as a conscious being, instinctively know (or think) that I am always unique, regardless of how many exact copies I make.
As I mentioned in another comment, I don't have a formal education on philosophy, so I am probably doing a terrible job trying to explain it. This question really makes sense when it clicks, so I suggest you to read it from a more qualified person's explanation.
[1] http://individual.utoronto.ca/benj/ae.pdf
[2] https://consc.net/papers/facing.pdf