But that's the part I never bought into about this part of the transhumanist genre. I get genetic engineering and cyber-implants, but uploading your actual "YOU" consciousness into a computer is never going to happen. All you'll get is an AI copy trapped in a meaningless existence, echoing fragments of a once living organism's mind. And all of those fragments can be stripped away through updates and editing.
Yeah, the whole "Back yourself up and live forever!" horseshit that transhumanists get into doesn't take in to account your gestalt. Look, if I make a backup of you, and you're both standing there, and I kill you, the you that's reading this right now? YOU are dead. It's over. Now, if you're a spiritual person, and you believe you go to an afterlife, rock on. But YOU YOU is dead. Your experience of the now, reality, is switched off. It doesn't jump over into the other person. From my perspective, that other you, that backup, is for my convenience. The only way around that is to transfer that gestalt from YOU to HIM. Not ctrl-c, ctrl-v, but ctrl-x, ctrl-v. And if the latter is done, and the copy you got ctrl-x/ctrl-v'ed into dies? You're still dead. Sure, if you face no hazards beyond aging, it is a way to live forever, but the minute someone kills whatever your consciousness - I mean YOUR consciousness, not a copy! - is in, then that's it. Game over.
Some people will bring up the whole "Aha, but when you go to sleep you effectively aren't the same person...!" Yes, you are. The gestalt continues, albeit through the surreal mindscape of unconscious dream, but the thread is unbroken. It's not like when I go to sleep tonight, I die, and a new Bill Silvey awakens tomorrow and keeps on chugging. That's not how it works. And if it is, at what point does the copy kick in? The minute I drift off to sleep? During deep REM? shallow sleep prior to awakening? And if you interrupt any of that, am I now both me and this hypothetical copy? No: sleep is a continuation of gestalt, not a termination of it, and a new gestalt begins at awakening.
Continuity of consciousness is a real philosophical question, and it's got nothing to do with sleep. The you of this second isn't the you of the last second. Quantum physics makes that even funkier, because we're not even made up of continuous matter. At the most basic level, we're just waveforms, distributions of probability. But the people who obsessed about the ultimate nature of reality are missing the point, because consciousness, and our perception of identity moving forward in time, is an illusion at any scale. And it's that illusion that matters, not the underlying physical reality. Cogito ergo sum; we experience consciousness and continuity, and that's what matters.
So the question them becomes what do all the copies experience? If you die, and wake up with all your memories in a digital form, then you have continuity. You've changed, yes, and may become someone very different from who you used to be, but you'd still be the same person, because you remember being that person. It's true the flesh is dead, and that may have been a real death for you when you were flesh, but you're now (digitally) alive, and you're still that dead person, as well. This isn't a conflict and shouldn't be, because the only continuity that still exists is the digital one.
Of course, if you didn't die and you're a copy of a living person, you still have that continuity, but now there are two of you. You've forked. There's another person, who isn't you, who shares the same continuity with you, up to a point. You could play games about who is real or who is original, but really you're both real and you both have the same trunk. You're just different branches.
And what if there's a way to merge those two branches? If the digital you could be updated with the flesh you's latest memories, or two digital copies that went their own ways and then came back together could be joined? This is the first time where the fork is internal to you. You'd have the trunk memories, shared by both, but then a branch, and two separate lines of continuity that you can remember and which are both you, before they merged back together. That would probably raise some psychological challenges, because humans are used to the illusion of linear, continuous time.
And if you wanted to get even more complicated, you could do a whole git-flow.