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?
Come to think of it, in reterospect I should have put more emphasis on the following:
What do people here think of Derek Parfit's theory of personal identity? On the face of it it seems pretty good as far as it goes, but what criticisms can be validly made of it?
I read Parfit's article "The Unimportance of Identity" and was incredibly frustrated. It reminded me of the Matrix Trilogy, in that it started out so well, but then bombed entirely at the end.
I was with him at first. I accept the Reductionist description of how the human mind works. But I became frustrated when he started insisting that identity didn't matter because, for instance, it might be possible to divide me into two identical persons. He argued that I couldn't be identical to two persons at once, but I see no problem with saying tha... (read more)