In my view that's just a different facet of the same class of problem. Your questions are implicitly dualist - positing that somehow your self could look out of different eyes. But if you were your brother, you'd have a different body, a different personality, a different set of memories, and you'd be wherever he is, doing whatever he's doing now.
And I would be aware of it, but I'm not. I can conceptualize having been someone different, so I'm not talking about my own self, per se. Non-dualism solves this problem (and a lot of problems, truth be told), but if my questions are dualistic, it's probably because materialism is a product of Cartesian dualism.
But what would that mean? how would you know? Your awareness is the unique product of your life experiences, how could it be different?
It could easily be different. To slip into theological language, this is quite clearly an aspect of contingent rather than necessary existence--it could have been otherwise and it could have not existed at all. Life experience doesn't break continuity of consciousness, so it's not an answer to this particular question.
I hope you find a satisfactory resolution.
Oh, idealism works just fine for me. I'm just venting my frustrations with ontological materialism the same way someone on the other side would with theistic ideas. Don't expect me to take illusions without aware subjects on faith, and I'll leave you alone about necessary existence.
BTW - I'm curious to know what your response would be to the apparent problems with panpsychism outlined in
this article. For me, it lacks evidence and explanatory & predictive power, but the article has more specific criticisms.
Yes, I know about the combination problem. I prefer versions of panpsychism that veer straight into idealism, so it doesn't really show up there, but it's an interesting problem for more naturalistic varieties. Still, if one views panpsychism in combination with emergentism, I'm not sure it's a greater issue when addressing mental phenomena as it is when unanticipated complexity emerges from physical systems. As for intermediate level consciousness, I don't really think that's outside of the realm of possibilities anyway--I wonder what goes on in the hive mind of an insect colony, for example. If the whole hive has its own consciousness, panpsychism survives but certain approaches to materialism do not.
On the other hand, these potential issues with panpsychism make it fairly counterintuitive. If awareness is present at all levels, then free will and selfhood are as likely to be illusory under panpsychism as they are under materialism. The only real difference between atomistic panpsychism and ontological materialism is that the former escapes the problem of saying that physical processes can conjure mental experience out of nothing.
Epistemologically, they seems to be on equal footing. If consciousness is an illusion, after all, from the outside there would be no difference between a situation where it "existed" and one where it did not. If we can't know whether or not consciousness is present on other levels under panpsychism, we also can't know whether the illusion of it is produced by other chemical reactions. One metaphysical position suggests that awareness is in some sense a fundamental property of matter and the other conjures it up as an illusion, but practically speaking, the results would be the same.