I have been trying to absorb the Lesswrong near-consensus on cryonics/quantum mechanics/uploading, and I confess to being unpersuaded by it. I'm not hostile to cryonics; just indifferent, and having a bit of trouble articulating why the insights on identity that I have been picking up from the quantum mechanics sequence aren't compelling to me. I offer the following thought experiment in hopes that others may be able to present the argument more effectively if they understand the objection here.
Suppose that Omega appears before you and says, “All life on Earth is going to be destroyed tomorrow by [insert cataclysmic event of your choice here]. I offer you the chance to push this button, which will upload your consciousness to a safe place out of reach of the cataclysmic event, preserving all of your memories, etc. up to the moment you pushed the button and optimizing you such that you will be effectively immortal. However, the uploading process is painful, and because it interferes with your normal perception of time, your original mind/body will subjectively experience the time after you pushed the button but before the process is complete as a thousand years of the most intense agony. Additionally, I can tell you that a sufficient number of other people will choose to push the button that your uploaded existence will not be lonely.”
Do you push the button?
My understanding of the Lesswrong consensus on this issue is that my uploaded consciousness is me, not just a copy of me. I'm hoping the above hypothetical illustrates why I'm having trouble accepting that.
At the risk of utter digression, I'm interested in this question of considering the other me to be me, post-split.
The way I experience identity clearly treats the results of various possible future branchpoints as roughly equivalent to one another (and equivalently associated to "me"), but does not treat the results of past branchpoints that way. A decision that has yet to be made feels very different from one that has already been made.
Normally it doesn't make much difference -- I don't have much difficulty treating the "me" that put on a different shirt this morning in some other Everett branch as sharing my identity, despite the branchpoint in the past, because we're so awfully similar -- but when we start introducing vast differences in experience, my ability to extend my notion of identity to include them proves inadequate.
The timeless approach you describe strikes me as a useful way of experiencing identity, but I can't imagine actually experiencing identity that way.
Is this perspective something that seems intuitively true to you, or is it something you've trained (and if so how?), or is it more that you are describing your intellectual rather than your emotional beliefs, or ...?
Just to be clear: this is entirely a question about human psychology; I'm not asking about the "actual nature of identity" out in the world (whatever that even means, if indeed it means anything at all).
It does seem like something that is intuitively true. I suspect having spent a lot of time considering bizarre duplication based counterfactuals has had some influence on my intuitions, bringing the intellectual and emotional beliefs somewhat closer together.
Also note that the emotion experience of identifying as 'me' isn't an all or nothing question. Even in everyday experience the extent to which I self identify as 'me' does vary - although always in the high ranges. Which parts are me? comes in to it here. So would experimenting with localized magnetic stimulation of certain parts of the brain, if you really looked at the science!
Note that I (guess I) would not continue to identify with the other me as me indefinitely. It would probably go from like looking at a mirror (an abstracted intellectual one in this example) to only a vague feeling of association over time and depending on stimulus.
In the other direction there are definitely parts of my past history that I don't experience as 'me' either - and not purely dependent on time. There are a couple of memories from when I was 5 that feel like me but some from even my twenties (I am less than thirty) that barely feel like me at all.
I compare this to the experience of turning into a vampire in Alicorn's luminosity fanfiction. (FYI: That means a couple of days of extreme pain that does not cause any permanent damage.) While being tortured I may not feel all that much identification with either pre-torture human me or post torture vampire me. As vamp-wedrifid I would (probably) feel a somewhat higher identification with past-human-wedrifid as being 'myself'. Say ballpark 80%. From the perspective of painful-half-turned-wedrifid the main difference in experience from the me in this Omega counterfactual would be the anticipation of being able to remember the torture as opposed to not. Knowing the way the time forks are set up It would make a little difference but not all that much.
Summary: Yes, the timeless perspective relates to actual anticipated experience not just intellectual abstraction.