Like Parfit, I find that my new reflective equilibrium places less importance on personal identity.
Why?
I have read Parfit-type arguments that advocate a reductionist concept of personal identity. I found them convincing. But it did not change my values at all, it just made me think about them more clearly. I came to realize that when I said someone is the "same person" as their past self, what it meant was something like "they have the same memories, personality, and values as the past person." But this didn't change my stance on anything. I still care about the same things I did before, I'm just better at articulating what those things are.
In my view, future people created by the means you mention do not have sufficiently similar memories, personalities, values, and psychological continuity with me to satisfy my desire to continue living. I want there to be other people in the future, but this is purely for idealistic and altruistic reasons, not because of any form of self-interest.
In fact, since studying Parfit's views on population ethics, I've actually come to the conclusion that personal identity is in some ways, the most important part of morality. I think that the "original sin" of population ethics was attempting to remove it from the equation. I'm not advocating unequal treatment of whichever people end up existing or anything like that. But I do think that a person's identity, in addition to their level of welfare, should determine whether or not their creation makes the world better or worse. A world with a lower total amount of welfare may be better than one one with a higher total, if the identities of its inhabitants are different (for instance, I would rate a world of humans with normal values to be better than a world full of wireheads, even if the wireheads are better off, as long as both worlds have positive total utility).
I want there to be other people in the future, but this is purely for idealistic and altruistic reasons, not because of any form of self-interest.
I think that on the reductionist understanding of personal identity, that distinction breaks down. Consider a fairly typical "altruistic" act: I see a person heavily loaded with packages and I hold the doors open for them. Why? Well, I can see that it would suck badly to have to deal with the doors and packages simultaneously, and that it would suck a lot less to deal with the doors and packages ...
Although Elizier has dealt with personal identity questions (in terms of ruling out the body theory), he has not actually, as far as I know, "solved" the problem of Personal Identity as it is understood in philosophy. Nor, as far as I know, has any thinker (Robin Hanson, Yvain, etc) broadly in the same school of thought.
Why do I think it worth solving? One- Lesswrong has a tradition of trying to solve all of philosophy through thinking better than philosophers do. Even when I don't agree with it, the result is often enlightening. Two- What counts as 'same person' could easily have significant implications for large numbers of ethical dilemnas, and thus for Lesswrongian ethics.
Three- most importantly of all, the correct theory has practical implications for cryonics. I don't know enough to assert any theory as actually true, but if, say, Identity as Continuity of Form rather than of Matter were the true theory it would mean that preserving only the mental data would not be enough. What kind of preservation is necessary also varies somewhat- the difference in requirement based on a Continuity of Consciousness v.s a Continuity of Psyche theory, for example should be obvious.
I'm curious what people here think. What is the correct answer? No-self theory? Psyche theory? Derek Parfit's theory in some manner? Or if there is a correct way to dissolve the question, what is that correct way?