On Tue, 8 Sep 2020 at 4:13 pm, Bruce Kellett <bhkellet...@gmail.com> wrote:
> On Tue, Sep 8, 2020 at 3:44 PM Stathis Papaioannou <stath...@gmail.com> > wrote: > >> On Tue, 8 Sep 2020 at 09:06, Bruce Kellett <bhkellet...@gmail.com> wrote: >> >>> On Tue, Sep 8, 2020 at 8:49 AM Stathis Papaioannou <stath...@gmail.com> >>> wrote: >>> >>>> On Mon, 7 Sep 2020 at 04:41, John Clark <johnkcl...@gmail.com> wrote: >>>> >>>>> On Sun, Sep 6, 2020 at 9:34 AM Bruno Marchal <marc...@ulb.ac.be> >>>>> wrote: >>>>> >>>>> >> I don't know what the hell to make of a "objective probability of >>>>>>> a possible subjectivity”. >>>>>> >>>>>> >>>>>> *> I give you an example. A person is multiplied by 100 and put in >>>>>> 100 different, but identical from inside rooms. Just the number of the >>>>>> room >>>>>> differs, like in some hostel. You seem to agree that, as long as they >>>>>> stay >>>>>> in the room, there is only one person. But the copies are asked to open >>>>>> the >>>>>> room, and the person was asked, before the experience what is the >>>>>> probability that when going out of the room, its number is prime.* >>>>>> >>>>> >>>>> In that thought experiment there is no objective probability because >>>>> John Clark is always in a prime numbered room or John Clark is not. >>>>> So there is only subjective probability. There is a 100% chance John Clark >>>>> will walk out, look at the number on the door and see a prime number, and >>>>> a >>>>> 100% chance he will not see a prime number. And the question "What is >>>>> the probability I will see a prime number?" has no answer because in >>>>> this hypothetical the personal pronoun "I" is ambiguous. >>>>> >>>>> However if you were to ask one of the individual John Clarks in one of >>>>> those rooms AFTER the duplication "What is the probability you will see a >>>>> prime number on the door when you walk out?" then that would be a >>>>> legitimate unambiguous question, and the answer would be 25% because there >>>>> are 25 prime numbers less than 100. But that probability would just be a >>>>> subjective probability because he is either in a prime numbered room or he >>>>> is not, So that probability figure must just be a measure of that John >>>>> Clark's ignorance. >>>>> >>>> >>>> The probability of interest is that one particular John Clark will see >>>> a prime number, >>>> >>> >>> >>> How do you avoid the clear dualist implications of this? What is it that >>> singles out the particular John Clark in whom you are interested? >>> >> >> Nothing singles him out, one is picked at random out of the 100, and the >> question is asked, what is the probability that this particular one will >> see a prime number? This is a different question to what is the probability >> that some John Clark will see a prime number. You are saying that the first >> question is - what? - boring, invalid, incomprehensible? >> > > > The question of dualism arises more acutely from the 1p perspective: "if I > am duplicated in the 100 rooms, what is the probability that I will see a > prime number?" Take a random selection from the 100: will that one be me? > If, for any possible selection, the answer is "yes, that will be me" (all > the copies are "me"), then the probability that "I" will see a prime is > one, since 25 of the "mes" will see primes. If only one selection will give > me, then you have dualism, and a 25% chance that I will see a prime. In > your account above, the selection is equivalent to just asking "if I select > a room at random, what is the probability that the door will have a prime > number?" The fact that there is a copy of JC in the room becomes irrelevant > to the probability, which is simply determined by the ratio of the number > of primes to the number of doors. > Dualism is the idea that there is a spirit separate from the body. If I am duplicated, there will be many versions of me. If I ask, “am I a version that sees a prime number?” that does not entail that I am a spirit separate from the body. If I ask “what is the probability that after duplication I will be a version that sees a prime number?” that also does not entail that I am a spirit separate from the body. As you say, the fact that there is a person who identifies as being me in the room does not make any difference to the calculation, and that is the probability I am interested in. I may be interested in this number, for example, if I am going to bet on whether I will see a prime number after duplication. If I have the opportunity to bet $20 for a $100 reward if I see a prime number I will accept the bet, whereas if I have to bet $30 for a $100 reward I will not. > -- 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 everything-list+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/everything-list/CAH%3D2ypW2a5P-3gneob85Ku1fq51wkMyzb-Mr%3DCYJ15VsvLZddw%40mail.gmail.com.
