> On 30 Sep 2015, at 10:10 PM, Bruce Kellett <[email protected]> wrote: > >> On 1/10/2015 12:44 am, Stathis Papaioannou wrote: >>> On 28 Sep 2015, at 12:26 AM, Bruce Kellett <[email protected]> >>> wrote: >>>>> >>>>> It's possible that there are no copies of you, but it seems implausible. >>>>> There would have to be infinite copies of other things, but not you. What >>>>> makes the non-copied configurations special? >>>> >>>> Nothing. It is just that they are a priori as likely as any other >>>> configuration. >>> >>> In an infinite random sequence of numbers it is possible that my phone >>> number appears once and never repeats, while other eight digit sequences >>> appear multiple times; but I wouldn't bet on it. > > An infinite random sequence of digits has certain well-defined probabilistic > properties. In particular, ll digits are equally likely, and all sequences of > any particular length are equally likely. If that were not so, the sequence > would not be random. So your phone number will occur many times. But this is > not a good analogy because it relies of the definition of a random sequence > of digits. We do not have any comparable uniformity definition for a > collection of universes.
A good guess is that the universe is infinite and every configuration of atoms repeats. If it is not infinite then a given configuration may not repeat. It could also be infinite but only some patterns repeat - others do not. There might be infinite copies of Mars, but only one Earth. That would be strange, but possible. That's what I thought you were proposing to fill an infinite universe with. >>> And even if you are duplicated as Tegmark suggests, so that there are many >>> copies far outside our O-region, or even our particle horizon, then there >>> is absolutely no possibilitiy of any interaction between these copies, so >>> their existence or non-existence can have no effect on you, so they are >>> irrelevant -- in principle, not just FAPP. >>>> >>>>> >>>>> They cannot interact with each other, but they are psychologically >>>>> continuous with each other. >>>> >>>> That is a meaningless assertion. Can you suggest any operational way in >>>> which you could establish the truth of such an assertion? Are you >>>> suggesting that psychological influences can travel faster than light? >>>> Objects outside our Hubble volume cannot now interact with us; objects >>>> outside our particle horizon can never have interacted with us and can >>>> never do so in the future. The expansion of space makes these interactions >>>> impossible. Psychology is not exempt from these physical facts. >>> >>> It follows from the meaning of the words "psychologically continuous". If I >>> have the same psychological properties as I did yesterday then I am >>> psychologically continuous with my yesterday self. It is nonsensical to >>> assert that yes, I remember everything I did yesterday, I have the same >>> personality that I did yesterday, the same cognitive abilities that I did >>> yesterday, etc., but I am not actually psychologically continuous, because >>> there has been some sort of physical discontinuity. In fact, it is >>> reflecting on this that should make it clear that physical change is >>> irrelevant to psychological continuity except insofar as the physical >>> change makes a psychological difference. If you feel the same, look the >>> same, behave the same etc. today as you did yesterday but you are informed >>> that advanced aliens performed a procedure X on you in your sleep, then >>> that means that whatever X was, it did not affect psychological continuity. > > That is irrelevant to the point being made. I was talking about purported > copies far outside our present particle horizon -- beyond any possibility of > physical influence either way. I contend that applying the words > "psychologically continuous" in this context is simply meaningless. > Psychological continuity is dependent on physical continuity -- even if only > in the transfer of a memory stick from one computer to another. If there is > no physical interaction of any kind, particularly if such interaction is > physically impossible, then the two persons are different, and have nothing > other than a chance resemblance. Nothing that happens to one can have any > effect on the other. > > Consequently, I maintain that the idea of psychological continuity over and > above physical continuity is meaningless. God could resurrect you using knowledge of your brain state prior to death, or by exhaustively reconstructing every possible human state, of which yours is one. In the latter case there would be no causal connection. How would you know the difference in order to complain to God that he did not maintain psychological continuity for you? >>>>>> The situation then is just like that with the disjoint worlds of the MWI >>>>>> in QM: the separate worlds are disjoint -- non interacting -- so their >>>>>> existence has no bearing on you or your future. In fact, Susskind and >>>>>> others have identified Tegmark's level I multiverse with the MWI of >>>>>> quantum mechanics. I think this identification is nonsense, but the >>>>>> relevance of the potential copies is the same in both cases -- zero! >>>>> >>>>> It is not zero if you could be any of the copies. >>> >>> It is generally held that there is no difference in the empirical >>> predictions of the various interpretations of QM, so some physicists >>> consider it is a waste of time even thinking about it. > > They have a point. > >>>> Demonstrate to me how this makes an operational difference. If it makes no >>>> measurable or operational difference, then, the relevance of the copies is >>>> precisely zero. >>> >>> There is one difference between the MWI and other interpretations, revealed >>> through the quantum suicide experiment, but this can't be used to gather >>> evidence to convince anyone else. > > Whether the idea behind the quantum suicide notion makes any sense is > debatable. But, as you say, it is not a way in which one can gather empirical > evidence one way or the other, though the absence of people 10,000 years old > tends to count against the idea. > >>>>>>> There is reason to believe that in fact the universe is infinite and >>>>>>> uniform; but if it is not, which is possible, the conditional argument >>>>>>> still stands. So, do you think you would experience the world >>>>>>> differently if there were infinite copies of you and of every possible >>>>>>> variation of you? >>>>>> >>>>>> No. Not that I believe that there are such copies, but even if there >>>>>> were, they would be of zero consequence for anything whatsoever. >>>>> >>>>> What would it mean for probability if your mind were spread over infinite >>>>> copies? >>>> Nothing, because it would make no operational difference to anything -- >>>> even if such a concept made any sense at all. >>> >>> You have IIRC said that there is a problem defining probabilities in an >>> infinite multiverse. Given that we observe certain probabilities, what does >>> this mean for the hypothesis that we are living in a multiverse? > Nothing much. Probabilities are simply the result of ignorance -- we don't > know what the outcome will be, so we gather evidence from the outcomes in > previous similar cases and calculate the chances. We do not have this > facility in the many worlds scenario since we only ever have evidence from > one world. > > Many worlds is nothing more than a hypothetical construct. There is no > concrete evidence one way or the other. And science goes with the evidence -- > in the absence of any evidence we have to say that we simply do not know. > Many worlds ideas are not without their problems, so it is by no means clear > that such scenarios have any intrinsic advantage. If the worlds are > non-interacting, as almost certainly is the case, then they have absolutely > no consequences for psychology or the problem of consciousness. You misunderstand what "psychological continuity" means. It can occur despite a lack of physical interaction. -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. 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