Hi Quentin,
> concerning "finite/infinite" number of steps, it seems to me that it is
> always possible to have a computation that will take an infinite number
> of steps to arrive at a particular state, since for any state, there
> exists an infinity of computational histories which go through it, so
> it
> seems to me that some of them needs infinite steps... Do I miss
> something ?
Yes. My fault. I was not clear enough. First it is obvious that any
states in the execution of the DU has only a finite 3-computations.
But, as you say, any states belong to an infinite set of computations,
and this justifies that from the first person point of view we can have
infinite past. I should have mention the 1-3 difference. Apology. (But
I would not say that some state *needs* an infinite 3-computation, that
one would not even be generated by the DU.
Regards,
Bruno
>
> Sincerely,
> Quentin Anciaux
>
> Le lundi 13 juin 2005 à 15:37 +0200, Bruno Marchal a écrit :
>> I agree with everything you say in this post, but I am not sure that
>> settles the issue. It does not change my mind on the preceding post
>> where we were disagreeing; which was that IF I must choose between
>>
>> A) splitted between 10000 finite hells and 1 infinite paradise
>> B) Splitted between 1 infinite hell and 10000 finite paradises
>>
>> where "finite" and "infinite" refer to the number of computational
>> steps simulating the stories of thoise hells and paradises, THEN I
>> should choose A.
>> This is because all finite stories have a measure "0". Infinite
>> stories, by their "natural" DU multiplications will have a measure
>> one.
>>
>> But we are on the verge of inconsistency, because in practice there is
>> no way to garantie anything like the finiteness of any computation
>> going through our states (this is akin to the insolubility of the
>> self-stopping problem by sufficiently rich (lobian) turing machine).
>>
>> The idea that I try to convey is that if I am in state S1, the
>> probability of some next state S2 depends on the proportion, among the
>> infinite stories going through S1 of those *infinite* stories going
>> also through S2. And all finite stories must be discounted.
>>
>> (It is not necessary I remain "personally" immortal in those infinite
>> stories, the measure is given by the stories going through my states
>> even if I have a finite 3-life-time in all of those stories).
>>
>> (btw, this entails also that comp implies at least infinite past
>> and/or
>> future for any universes supporting our present story).
>>
>> [Note that here I am going far ahead of what I can ask to the lobian
>> machine, because our talk involves quantifiers on stories and that's
>> very complex to handle. Well, to be sure I have till now only been
>> able
>> to translate the case of "probability one", in machine term; but it is
>> enough to extract non trivial information on the logic of "observable"
>> proposition.]
>>
>>
>>
>> Bruno
>>
>>
>>
>>
>> Le 13-juin-05, à 13:00, Stathis Papaioannou a écrit :
>>
>>> I have been arguing in recent posts that the absolute measure of an
>>> observer moment (or observer, if you prefer) makes no possible
>>> difference at the first person level. A counterargument has been
>>> that,
>>> even if an observer cannot know how many instantiations of him are
>>> being run, it is still important in principle to take the absolute
>>> measure into account, for example when considering the total amount
>>> of
>>> suffering in the world. The following thought experiment shows how,
>>> counterintuitively, sticking to this principle may actually be doing
>>> the victims a disservice:
>>>
>>> You are one of 10 copies who are being tortured. The copies are all
>>> being run in lockstep with each other, as would occur if 10 identical
>>> computers were running 10 identical sentient programs. Assume that
>>> the
>>> torture is so bad that death is preferable, and so bad that escaping
>>> it with your life is only marginally preferable to escaping it by
>>> dying (eg., given the option of a 50% chance of dying or a 49% chance
>>> of escaping the torture and living, you would take the 50%). The
>>> torture will continue for a year, but you are allowed one of 3
>>> choices
>>> as to how things will proceed:
>>>
>>> (a) 9 of the 10 copies will be chosen at random and painlessly
>>> killed,
>>> while the remaining copy will continue to be tortured.
>>>
>>> (b) For one minute, the torture will cease and the number of copies
>>> will increase to 10^100. Once the minute is up, the number of copies
>>> will be reduced to 10 again and the torture will resume as before.
>>>
>>> (c) the torture will be stopped for 8 randomly chosen copies, and
>>> continue for the other 2.
>>>
>>> Which would you choose? To me, it seems clear that there is an 80%
>>> chance of escaping the torture if you pick (c), while with (a) it is
>>> certain that the torture will continue, and with (b) it is certain
>>> that the torture will continue with only one minute of respite.
>>>
>>> Are there other ways to look at the choices? It might be argued that
>>> in (a) there is a 90% chance that you will be one of the copies who
>>> is
>>> killed, and thus a 90% chance that you will escape the torture,
>>> better
>>> than your chances in (c). However, even if you are one of the ones
>>> killed, this does not help you at all. If there is a successor
>>> observer moment at the moment of death, subjectively, your
>>> consciousness will continue. The successor OM in this case comes from
>>> the one remaining copy who is being tortured, hence guaranteeing that
>>> you will continue to suffer.
>>>
>>> What about looking at it from an altruistic rather than selfish
>>> viewpoint: isn't it is better to decrease the total suffering in the
>>> world by 90% as in (a) rather than by 80% as in (c)? Before making
>>> plans to decrease suffering, ask the victims. All 10 copies will
>>> plead
>>> with you to choose (c).
>>>
>>> What about (b)? ASSA enthusiasts might argue that with this choice,
>>> an
>>> OM sampled randomly from the set of all possible OM's will almost
>>> certainly be from the one minute torture-free interval. What would
>>> this mean for the victims? If you interview each of the 10 copies
>>> before the minute starts, they will tell you that they are currently
>>> being tortured and they expect that they will get one minute respite,
>>> then start suffering again, so they wish the choice had been (c).
>>> Next, if you interview each of the 10^100 copies they will tell you
>>> that the torture has stopped for exactly one minute by the torture
>>> chambre's clock, but they know that it is going to start again and
>>> they wish you had chosen (c). Finally, if you interview each of the
>>> 10
>>> copies for whom the torture has recommenced, they will report that
>>> they remember the minute of respite, but that's no good to them now,
>>> and they wish you had chosen (c).
>>>
>>> --Stathis Papaioannou
>>>
>>> _________________________________________________________________
>>> Express yourself instantly with MSN Messenger! Download today - it's
>>> FREE! http://messenger.msn.click-url.com/go/onm00200471ave/direct/01/
>>>
>>>
>> http://iridia.ulb.ac.be/~marchal/
>>
>>
>
>
http://iridia.ulb.ac.be/~marchal/
Received on Mon Jun 13 2005 - 10:26:43 PDT