Stathis Papaioannou writes: > Returning to your example, if God creates a person, call him A, and a day > later kills him, A will be really dead (as opposed to provisionally dead) if > there will never be any successor OM's to his last conscious moment. Now, > suppose God kills A and then creates an exact copy of A along with his > environment, call him B, on the other side of the planet. B has all of A's > memories up to the moment before he was killed. This destruction/creation > procedure is, except for the duplication of the environment, exactly how > teleportation is supposed to work. I think most people on this list would > agree that teleportation (if it could be made to work, which not everyone > does agree is possible) would be a method of transportation, not execution: > even though the original dies, the copy has all his memories and provides > the requisite successor OM in exactly the same way as would have happened if > the original had continued living. So in the example above, if B is an exact > copy of A in an exact copy of A's environment, A would "become" B and not > even notice that there had been any change.
I'm not sure I would put it like this, although I agree that this would probably become a common way of describing it. But there are some aspects of the process by which A becomes B which are different from our usual, moment-to-moment continuity of identity. One obvious difference is that it is a divine miracle. This can hardly be neglected. Even if we imagine this being done technologically rather than miraculously, with A's brain being scanned and transmitted to where B will be created, the process of making this scan will increase the measure of that OM for A by virtue of storing it in extra places. This may manifest as the potential for future copies of A to be created starting with that exact mental moment. People may come to view transporting as a dangerous activity which puts them at risk of the creation of unauthorized copies. These are all ways in which seemingly abstract and metaphysical questions become manifest in the real world. I think it is important to see that these are not merely imperfections in the thought experiments which we should ignore in the interests of getting at the real issues. In my model, the number of implementations is all important. It is a major determinant of measure. Any technology which messes around with this stuff is likely to affect the measure of the relevant observer moments. Having your mental state recorded increases its measure, which manifests physically as a greater chance that it can interact with the world. > Now, consider the same situation with one difference. Instead of creating B > at the instant he kills A, God creates A and B at the same time, on opposite > sides of the planet but in exactly the same environment which will provide > each of them with exactly the same inputs, and their minds at all time > remain perfectly synchronised. God allows his two creatures to live for a > day, and then instantly and painlessly kills A. In the previous example, we > agreed that the creation of B means that A doesn't really die. Now, we have > *exactly* the same situation when A is killed: B is there to provide the > successor OM, and A need not even know that anything unusual had happened. > How could the fact that B was present a day, a minute or a microsecond > before A's death make any difference to A? All that matters is that B is in > the correct state to provide continuity of consciousness when A is killed. > Conversely, A and A's death cannot possibly have any direct effect on B. It > is not as if A's soul flies around the world and takes over B; rather, it > just so happens (because of how A and B were created) that B's mental states > coincide with A's, or with what A's would have been if he hadn't died. If we focus on observer-moments, there are no A and B as separate individuals. There are two instantiations of a set of OMs. Each OM has double measure during the time that A and B exist, then it has single measure after A has been destroyed. It is meaningless to ask, after A dies, if B is now A or still B, or maybe both? (I am curious to know how you would try to answer this question, using your terminology!) Rather, there is then a single instantiation of the set of OMs. > Who's measure is decreased here, A's or B's? How would any of them know > their measure had been decreased? It seems to me that neither A nor B could > *possibly* be aware that anything had happened at all. The only benefit of > having multiple exact copies of yourself around would seem to be as backup > if one is destroyed. If your measure were surreptitiously increased or > decreased, what symptoms would you expect to experience? Well, we've been discussing this all along, and I have tried to answer it several times, but I can only do so by analogy. Having your measure decreased is like having a chance of dying. Having it increased is like... well, I can't analogize it to anything, because it has never been possible and we have no experience of it. Only if technology advances to allow mental copies will it be possible for us to increase measure. What will it be like? It will be like gaining greater influence over the world, greater ability to put our plans into fruition (just as death represents a loss of those abilities). > What about if you > were a piece of sentient software: surely having multiple instantiations of > the ones and zeroes could not make any difference; if it did, wouldn't that > be a bit like expecting that your money would have greater purchasing power > if your bank backed up their data multiple times? Or like saying that > "2+2=4" would be more vividly true (or whatever it is that increasing > measure causes to happen) if lots and lots of people held hands and did the > calculation simultaneously? I don't think those are accurate analogies. Your money would not have multiple purchasing power if it were backed up multiple times, but that information would have greater measure. Measure is a property of information. When the information about your money has greater measure, this will tend to give it greater robustness and more opportunity to interact with and influence the world. Specifically, it can't be deleted and lost as easily. Multiple backups have real value and any legitimate bank will make sure to use them. > I can't be completely sure that increasing your measure would have no > effect. Maybe there would be some sort of telepathic communication between > the various copies, such as is said to occur between identical twins, or > some as yet undiscovered physical phenomenon. However, there is absolutely > no evidence at present for such a thing, and I think that until such > evidence is found, we should only go on what we know to be true and what can > logically be deduced from it. No, I have absolutely no expectation of any such nonphysical effects from increasing measure. I am confident that we agree about the third-party effects of making copies. No copy will demonstrate that he is able to read the minds of his fellows. I can only say that increasing measure is the opposite of decreasing measure, that our measure decreases every day, and that we fight as hard as we can to keep it from decreasing faster. I believe that you view this fight as a philosophical mistake, but your genes don't agree! Your genes are not content to have just one copy. A gene doesn't say, it doesn't matter how many of me there are, as long as at least one exists I am still alive. No, each gene fights its hardest to increase its measure. It wants to occupy as much of the universe as it can. It wants to increase its influence, its redundancy, its robustness. This is what increasing measure means to your genes. If people lived in a regime where increasing measure were possible, I believe they would come to adopt similar views, and for the same reason our genes did. Hal Finney