It seems we're losing track of the original objection, which is to say that:
1. everything exists (all relationships are equally valid, all worlds
exists, you can string 'snapshots in time' together any way you wish - with
a glass unsmashing or whatever - and all are equally likeley, as all exist
with a probability off one.)
and 2. WAP (we see a stable environment suited to us because we otherwise
wouldn't be here to see it).
...seem to explain the entire universe, except in that there's nothing
stopping temporary minor abberations such as a flying rabbit.
I haven't been reading recent posts but from this one I don't think we're
much closer than we were a few months ago. Am I wrong (I hope so). And if
so, can someone explain why in one simple paragraph?
James
> -----Original Message-----
> From: Marchal [SMTP:marchal.domain.name.hidden]
> Sent: Thursday, October 21, 1999 11:44 AM
> To: Juergen Schmidhuber; everything-list.domain.name.hidden
> Subject: Re: Turing vs math
>
>
> I agree a lot with the last post by Juergen Schmidhuber.
>
> I take the opportunity to describe briefly the difference between
> Schmidhuber and me. It is relevant for the current Alistair-Russell
> debate (IMHO).
>
> i-POV means from the ith person point of view (i = 1 or 3).
>
> I don't take the notion of observer for granted. I modelise it
> with the notion of self-referentially correct universal machines.
> This put very high constraints on the concept of communicable
> proposition (3-POV), knowable truth (1-POV), observable facts
> (3-communicable and 1-non-communicable like qualia).
> This entails also different logic for the 3-POV and 1-POV.
>
> The PE-omega experience (see below) shows that the computationalist
> hypothesis entails that the physical
> laws emerge on the possible 1 and 3 discourses of the
> self-referentially correct universal machines.
>
> In my thesis http://iridia.ulb.ac.be/~marchal I show that indeed
> a precise quantum logic comes from the logic of 3-observation.
>
> This entails that at some point I think Juergen is a little to rapid.
> For exemple when Schmidhuber write
>
> >The prior U suggests: you are in the simplest universe compatible with
> >your existence. The conditional probability of some universe, given
> >yourself, is high if that universe is computable by a short algorithm. To
> >use the example in [1], a universe in which lambs start attacking lions
> >seems less probable than the present one, because apparently it requires
> >more information than conveyed by the few physical laws causing "normal"
> >animal evolution. Similarly for "flying rabbits".
>
> The problem is that "to be in a universe" has no clear meaning with
> comp. (Independently that the argument of the short algorithm is
> probably correct and fundamental). The hunting of the flying rabbit is
> basically correct, but even with my precise notion of observer
> it is not so easy to solve it completely).
>
> Here is a copy of my concise formulation of the Universal Dovetailing
> argument from a older post (the PE-omega experience as I call it in
> this list). It gives the explanation that the whole UD* must be taken into
> account to define the measure on computational histories.
> I recopy it because it is not easily readable in the archive (the lines
> are too long).
>
> ==========
> Begin copy
>
> UD, the Universal Dovetailer, is equivalent to Schmidhuber
> Great Programmer.
> UD is a finite program.
> UD* is the infinite extension of the UD.
>
> James Higgo wrote:
>
> >Bruno, you say "you can only associate mind with the
> >whole UD*." - I'm not sure why.
>
> Here is a short answer. Take your time to read it, and please tell
> me if you disagree at some point.
> It is necessary to concentrate ourself on the following thought
> experiments (PE, PE1, PE2, PE3, PE4, PE-omega).
>
> The "practitionners" of computationnalism can use classical
> teletransport as a mean to move from one place A to another
> place B. This mean he is "read" at A, send (by wave radio,
> for exemple) at B, annihilated at A, and reconstituted at B.
> Let us call that experience : the primitive experience or
> simply the PE.
>
> Let us look first at two independent changes of the PE.
>
> PE1 : if, knowing it or without knowing it, the reconstitution
> is time-delayed at B, this doesn't change anything from his
> first-person point of view. In particular if he is certain to
> get B with PE, he must be certain to get B, in PE1.
> (The delay is supposed to be finite).
>
> PE2 : if he is told he will be reconstituted at B and B',
> his first-person futur is undetermined. The domain of
> undeterminism is {B, B'}.
> Of course, from a third person point of view, everything
> is determined.
>
> Do you agree until here ?
>
> Now, consider the following experience PE3 which mixed PE1
> and PE2.
> He is told that he will be reconstituted at B and at B'
> (like PE2), but a time-delay of reconstitution is introduced
> at B (like PE1).
> Now, if you agree with what I say about PE1 and PE2,
> you should agree with :
>
> IF he quantifies the indeterminism on {B, B'} in some way
> for PE2, THEN he must give the same quantification for
> the indeterminism on {B, B'} with PE3.
> For exemple, if he quantifies {B, B'} with a uniform
> probability distribution with PE2, he must quantify {B, B'}
> with a uniform probability distribution with PE3. To sum up,
> the delay doesn't change his expectation.
>
>
> This follows from comp (think on the first-person communication
> by the average robot instead of you, for exemple). The average
> robot = the normal (gaussian) robot when these duplication
> experiences are iterated.
>
> OK ?
>
> I guess you will also accept that nothing will change, in
> neither PE nor PE1 nor PE2, nor PE3, if at B (for exemple)
> he is reconstituted in a perfect virtual environment
> (which could exist by COMP). This is PE4.
>
> If you agree, you are ready for "PE-omega", which is just
> the infinite running of the UD.
>
> Suppose that you are in some state of mind s, captured at
> some digital level by a computationnal state S (which exist
> by COMP, and there is no restriction on the level other than
> permitting digitalisable capture).
>
> Now suppose the UD is running, and that it never ends
> (accidentally). Then you will be virtually reconstituted,
> in the state S, an infinite number of times in the all UD*.
>
> End copy.
> =====================================
>
> Because your 1-feeling doesn't depend on the time when the
> UD access your state of mind, the whole (infinite) UD* is needed
> in the definition of the measure on the computational histories.
>
> Now, either with the movie argument (the marchal-maudlin
> crackpot proof as Jacques M Mallah once put it) or with some strong
> Occam razor, the UD doesn't need to be physically implemented.
>
> Note also that the UD dovetails on the oracle computations, so that
> the "non computable stuff" could still have an important role
> with comp. (I say that before).
>
> Bruno
Received on Thu Oct 21 1999 - 06:18:30 PDT