The biggest assumption is number 3, continuity of matter. If we take the Star Trek transporter and use it to copy and remake you from planet to Enterprise, The new you may only think it is you, but it would not be you looking out through its eyes. Other people couldn’t tell, IT couldn’t tell, but it would be a new consciousness that only thinks it is you.
Your memory and personality would continue, yes. But that is not you, not really. The real you is your consciousness, the part that’s receiving the experiences — and that part got disintegrated down on the planet by the transporter beam. Memory comes and goes, but your consciousness is the indispensable component.
This view seems like common sense, but the trouble with it is that it implies your consciousness is illusory, that there’s nobody in there actually experiencing and feeling anything — just a squishy brain and vague set of memories going through the motions and twitching on command like a frog’s leg attached to an electrode. Nobody’s really home, just a set of instructions and memories that pretend to be alive as a consequence of a long series of evolutionary changes in an utterly infinite and utterly pointless universe. Fancy robots.
But I don’t FEEL like a robot. I’ve read a lot of talk recently that consciousness seems to be something special, a property of the universe like magnetism and gravity that arises whenever certain conditions are met. Perhaps “you” have a certain signature, like a memory address, that gets connected whenever a sufficiently exact copy of the consciousness machinery is intact and working. Or perhaps it’s something more blurry and broad than that, a spectrum of “yous” that are all similar, a quantum hall of mirrors, each version slightly different from the next extending off into the infinite mathematical horizon forever, until they become so different as to no longer really be you at all.
If something like this is the case, then yeah, you’ll live again whenever conditions arise that are a sufficient match to your consciousness (a.k.a. your soul). You may or may not remember who you were, but you’ll experience things again, and the subjective time spent in between lives is probably no time at all.
