If the duplicate says "I did X on my nth birthday" it's not true since it didn't even exist. If I claim that I met Shakespeare you can say, "But you weren't even born!" So what does the duplicate say when I point out that it didn't exist at that time? "I did but in a different body" (or "I was a different body")? That implies that something has been transferred. Or does it say, "A different body did, not me"? But then it has no relationship with that body at all. Or perhaps it says, "The Original did X on their nth birthday and the Original has given me permission to carry on its legacy, so if you have a question about those events, I am the authority on them now"? It gets very difficult to call this "memory." I suppose you could say that the duplicate doesn't have the original's memories but rather has knowledge of what the original did, but then in what sense is it a duplicate?
If the duplicate says "I did X on my nth birthday" it's not true since it didn't even exist.
Correct.
So what does the duplicate say when I point out that it didn't exist at that time?
When talking to you, or someone who shares your attitude, my duplicate probably says something like "You're right, of course. I'm in the habit of talking about my original's experiences as though they're mine, because I experience them as though they were, and both I and my original are perfectly happy talking that way and will probably keep doing so. But...
In June 2012, Robin Hanson wrote a post promoting plastination as a superior to cryopreservation as an approach to preserving people for later uploading. His post included a paragraph which said:
This left me with the impression that the chances of the average cryopreserved person today of being later revived aren't great, even when you conditionalize on no existential catastrophe. More recently, I did a systematic read-through of the sequences for the first time (about a month 1/2 ago), and Eliezer's post You Only Live Twice convinced me to finally sign up for cryonics for three reasons:
I don't find that terribly encouraging. So now I'm back to being pessimistic about current cryopreservation techniques (though I'm still signing up for cryonics because the cost is low enough even given my current estimate of my chances). But I'd very much be curious to know if anyone knows what, say, Nick Bostrom or Anders Sandberg think about the issue. Anyone?
Edit: I'm aware of estimates given by LessWrong folks in the census of the chances of revival, but I don't know how much of that is people taking things like existential risk into account. There are lots of different ways you could arrive at a ~10% chance of revival overall:
is one way. But:
is a very similar conclusion from very different premises. Gwern has more on this sort of reasoning in Plastination versus cryonics, but I don't know who most of the people he links to are so I'm not sure whether to trust them. He does link to a breakdown of probabilities by Robin, but I don't fully understand the way Robin is breaking the issue down.