> "There’s no guarantee that this ‘being’ would be the same one who first entered into the cryogenic process, either. As de Grey says, the question remains of “whether scanning the brain and uploading it into a different substrate is revival at all, or if you’d be creating a new individual with the same characteristics.”

I think this is probably a bit misleading. I can't imagine de Grey being anything other than reductionist in his views about the mind, so I can only imagine his interpretation of this question to be as follows: "has the scanning process captured all the relevant information about the person's mind?" Have you created a new person (by missing out some information from the original's physical instantiation), one who is perhaps very similar to the original, but where some details are different because the scan was not of high enough fidelity?

Of course, it's still unknown whether it's even possible to extract sufficient detail from the brain; if by unhappy chance it turns out that some of the quantum details of the brain's state are important to the mind, then it's possible we may simply never be able to copy a person. Let us hope that is not the case.