On 12 August 2017 at 12:12, Bruce Kellett <[email protected]> wrote:
> On 12/08/2017 3:22 am, Bruno Marchal wrote: > >> On 11 Aug 2017, at 13:40, Bruce Kellett wrote: >> >>> >>> Are you telling us that P(W) ≠ P(M) ≠ 1/2. What do *you* expect when >>>> pushing the button in Helsinki? >>>> >>> >>> I expect to die, to be 'cut', according to the protocol. The guys in W >>> and M are two new persons, and neither was around in H to make any >>> prediction whatsoever. >>> >> >> Fair enough. >> >> You think the digital mechanism thesis is wrong. >> > > Correct. > > There is a fundamental problem with your person-duplication thought > experiments. This is that the way in which you interpret the scenario > inherently involves an irreducible 1p-3p confusion. The first person (1p) > concerns only things that the person can experience directly for himself. > It cannot, therefore, involve things that he is told by other people, > because such things are necessarily third person (3p) knowledge -- > knowledge which he does not have by direct personal experience. So our > subject does not know the protocol of the thought experiment from direct > experience (he has only been told about it, 3p). When he presses the button > in the machine, he can have no 1p expectations about what will happen > (because he has not yet experienced it). He presses the button in the > spirit of pure experimental enquiry -- "what will happen if I do this?" His > prior probability for any particular outcome is zero. So when he presses > the button in Helsinki, and opens the door to find himself in Moscow, he > will say, "WTF!". In particular, he will not have gained any 1p knowledge > of duplication. In fact, he is for ever barred from any such knowledge. > > If he repeats the experiment many times, he will simply see his > experiences as irreducibly random between M and W, with some probability > that he can estimate by keeping records over a period of time. If you take > the strict 1p view of the thought experiment, the parallel with the early > development of QM is more evident. In QM, no-one has the 3p knowledge that > all possible outcomes are realized (in different worlds). > > So, before pressing the button in H, his prior probabilities are p(M) = > p(W) = 0, with probably, p(H) = 1. On the other hand, if you allow 3p > knowledge of the protocol to influence his estimation of probabilities > before the experiment, you can't rule out 3p knowledge that he can gain at > any time after pressing the button. In which case, the 1p-3p confusion is > complete, p(M) = p(W) = 1, and he can expect to see both cities. In that > case, the pure 1p view becomes irrelevant. The subject directly experiences the details of the experimental protocol, through hearing or reading about it. All knowledge is 1p; information from the external world comes to me via my senses and affects my knowledge. -- Stathis Papaioannou -- 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]. To post to this group, send email to [email protected]. Visit this group at https://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
