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, not that some John Clark will see a prime number. A gambler who buys a lottery ticket is interested in the probability that one particular gambler will buy the winning ticket, not the probability that some gambler will buy the winning ticket, which he knows is 1 if all the tickets are sold. -- 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%3D2ypVQva5GguKQRnMvN-pjRDd0oPR2YnUKBv_N24PGACY1Cw%40mail.gmail.com.
