Russell Standish wrote:

On Fri, Jun 10, 2005 at 12:22:24AM -0400, Jesse Mazer wrote:
>
> Hal didn't say anything about only sampling the birth moment randomly
> according to the absolute measure, or imply it as far as I understood him.
>

The RSSA is applied to the "next" OM, so can only predict
probabilities of OMs that have a predecessor. A birth moment has no
predecessor by definition. Usually you would expect to apply the SSA
which applies to an absolute measure over birth moments. If you want
to apply some other principle, then you're welcome, but it would be a
little strange.

Well, an advocate of the pure RSSA approach might simply say that it's not a well-defined question to ask what the probability of one birth moment vs. another is, that it only makes sense to talk about the probability of different possible successors to your current OM. Also, if you accept absolute probabilities, conditional probabilities, and the immortality of all streams of consciousness as I do, then it seems to me a necessary consequence of this that streams of consciousness are neither created or destroyed, so there's no such thing as "birth moments" in your sense. In terms of the water tank analogy, if you want the amount of water in each tank to stay constant over time (no change in the absolute probabilities, since there's no time at the level of the multiverse as a whole), then if water molecules are not destroyed they can't be created either. As I said earlier, it seems to me if you want to believe both in immortality and the idea that your current OM is fairly typical (as suggested by the ASSA), you need some kind of "immortality with amnesia"--I suggested two ways that could work in that earlier post.



>
> No, I'm not saying there is no "next" OM, my point was that the two methods > can give different probabilities for my next OM--for example, a Jesse Mazer > OM and a Russell Standish OM might have about equal absolute measure, but
> given my current OM, a Jesse Mazer OM would have much higher relative
> measure.

Yes, of course.

OK, is that why you're saying the ASSA and RSSA are incompatible? But my point is that I think this incompatibility is removed if you always take the ASSA as applying to your current observer-moment, and the RSSA as applying to your next observer-moment. This may seem like nonsense because your "next" observer-moment will become "current" when you are experiencing it, but I don't think it is. Remember that the information available to you changes over time, you know nothing more than the content of your current observer-moment--in terms of the water-tank analogy, the molecules have no independent "memory" of where they've been in the past, they only know their current tank (the tank itself may have 'memories' of some sort, but they will be compatible with multiple possible past tanks). So suppose we calculate the absolute probability of different possible OMs being my "next" experience *without* taking into account specific knowledge of what my current OM is, by doing a sum over the absolute probability of each OM being my current experience multiplied by the conditional probability that that OM will be followed by the OM whose probability of being my "next" experience we want to calculate. If we just had 3 possible OMs labelled A, B, and C, then we'd do: P(C is next) = P(A is current)*P(A -> C) + P(B is current)*P(B -> C) + P(C is current)*P(C -> C). The condition I talked about earlier that there is no change in the absolute probabilities, that the level of water in each tank doesn't change because the water flowing out is balanced by the water flowing in, is equivalent to imposing the requirement that P(C is next) = P(C is current), which means that the vector of absolute probabilities must be an eigenvector of the matrix of conditional probabilities with eigenvalue 1:

P(A)*P(A -> A) + P(B)*P(B -> A) + P(C)*P(C -> A) = P(A)
P(A)*P(A -> B) + P(B)*P(B -> B) + P(C)*P(C -> B) = P(B)
P(A)*P(A -> C) + P(B)*P(B -> C) + P(C)*P(C -> C) = P(C)

This is the constraint that I think might help to determine a unique self-consistent probability distributions for both absolute and conditional probability, an idea I discussed in the "Request for a glossary of acronyms" thread. And if you impose this constraint, it means that if you calculate the probability of experiencing different possible OMs as your "next" experience without specific knowledge of what your "current" experience is, then the probability you get for having a given OM as your next experience is exactly the same as the absolute probability of that OM being your current experience. So this is why I think there is no incompatibility between the ASSA and the RSSA, if you define them in the way I do.

Jesse


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