>
> On Thu, 23 Sep 1999, Russell Standish wrote:
> > > > The properties ascribed to that class should therefore be
> > > > invarient of the exact definition.
> > >
> > > Obviously it does stop us since we disagree on the properties.
> >
> > Which properties did you have in mind?
>
> See the cloning example.
Why such interest in the cloning example? I'm sure we could come up
with a consistent framework for dealing with this example, however, at
present I don't see the point, so I deliberately exclude it from
discussion.
>
> > > [JM wrote]
> > > > > > > There is no randomness in the ASSA. That would require an
> > > > > > > identity function (mind-like hidden variables) + new laws of physics that
> > > > > > > are stochastic. *Effective* probability + deterministic phyics only,
> > > > > > > please.
> > > > > >
> > > > > > The Sampling of the SSA term implies a random selection process. Over
> > > > > > and above that, of course there is no additional randomness required.
> > > > >
> > > > > NO. In my view everything is deterministic. There is NO
> > > > > randomness. Just a lot of observers with different observations.
> > > > > *Effective* probability is proportional to the number/measure of those.
> > > >
> > > > What about what your observers actually observe? That is random.
> > >
> > > What we have here is a failure to communicate. I don't know how
> > > to convey an idea you don't seem to understand. I hope I won't have to
> > > keep trying. The idea is very very simple after all.
> > > Suppose there are 1000 observers. For simplicity, assume each can
> > > be labeled by a brain state which we can number from 1-1000, and that each
> > > sees a different observation, which we can label by the observer number N.
> > > Consider number 463. He sees an observation with various
> > > characteristics, which we have labeled #463.. There is NOTHING random
> > > about that, not in any way, shape or form, at all. Period. I can't
> > > emphasize that enough.
> >
> > Emphasize all you like. It sounds like a typical statistician's
> > procedure for defining a stochastic process.
>
> BS. Retract that statement or justify it.
>
> The truth is you won't find a definition of "stochastic" in a math
> book, except for an informal discussion in the first chapter. It is a
> primitive concept, and the human brain has an idea about it, but the math
> is forced to deal with probabilities using deterministic measure theory.
> However there should be no confusion since the distinction I made
> above is very clear. Did our observer #463 see observation #463 by
> chance? NO. In a way he *is* observation #463.
Fine - mathematics has a habit of squeezing out conceptual markers in
the process of promoting rigour. Great for proving theorems, but lousy
for promoting understanding. Either we simply chose not to use the
words random and stochastic, and confine ourselves to dicsussion of
mathmatical theorems, or we define the terms to mean the above. I
don't see that there is anything wooly about this.
>
> > > Nor does he have any direct evidence to prove that the other
> > > observers exist. But what he can do is guess that they exist based on
> > > Occam's razor, thinking "the world would be simpler if I were one out of
> > > 1000 observers".
> > > Suppose that each observer sees 10 coins. Our observer #463
> > > notices that 9 out of the 10 are tails up, 1 is heads up. He guesses that
> > > most observers see mostly tails up coins. In other words, he guesses that
> > > the effective probability for each coin to be tails up is large.
> > > To find out if this guess is correct we would "take a survey" of
> > > all the observers. Still nothing random from any point of view.
> >
> > Agregating statistical properties reduces the level of randomness in
> > the description. In the infinite limit (or thermodynamic limit if you
> > prefer that term) one should be left with a deterministic system.
>
> What does that have to do with anything? You don't seem to be
> responding to anything I wrote, just pulling random stuff out of thin air.
>
Au contraire - the process you just described in the previous
paragraph goes by many names, such as the thermodynamic limit, the law
of large numbers etc. etc.
> > > Of course, the results of the survey are the same as if the coins
> > > were randomly distributed with the appropriate probabilities. Hence the
> > > term effective probability.
>
> This is the main point I was making. An effective probability is
> nothing like a stochastic probability, except for practical purposes, that
> is.
Since you've agreed that stochasticity is merely a practical label for
a well defined mathematical theory (which you'd prefer to remain
nameless), then it would appear that your effective probability is
identical to stochastic probability. This is playing with words, and
unproductive.
>
> > > > In our case, the ASSA and the RSSA are
> > > > probably connected by a measurement theory of quantum mechanics,
> > > > something about which we have only the vague outline at present.
> > >
> > > That's BS. They are plainly incompatible since they give
> > > conflicting predictions. They are not just different levels of
> > > description. And I see no reason why invoking QM would change anything.
> > > On the contrary, we already know the physics, what we need for a
> > > measurement theory are precisely things like the ASSA + computationalism.
> >
> > Tell me how they give conflicting predictions? You cannot conclude
> > from ASSA that an observer will not observe an arbitrarily large age,
> > unless of course you assume the "random hopping" interpretation, which
> > you have quite explicitly (and in my opinion quite rightly) ruled
> > out. ASSA in this case simply has no predictive power over what
> > histories observers will see. The RSSA, on the other hand will predict
> > this, provided a number of other (reasonably believable) assumptions
> > are taken. There's no conflict here. What other predictions are in conflict?
>
> That is complete nonsense. Of course no observer ever saw
> 'histories' with the definition of observer I have used above. You see
> one observation.
Why not? Isn't the observation of memory traces - whether they be
within our own brain, or preserved in history books, fossil records,
computer databases and the like - an observation of a history?
> The ASSA, together with our theories of physics, very obviously
> implies that the effective probability of observing a large age is quite
> low. This is effectively a prediction, and most observers will find it to
> be correct. Using simple Bayesian reasoning, effective predictions are
> just as good as any other predictions. In particular, you can plug the
> effective conditional probabilities into the Baysian formula to update
> priors about proposed models of reality. In this case to endorse ASSA and
> reject RSSA.
>
Why, when Bayesian reasoning works fine in both pictures, and neither
view is incompatible.
I disagree that ASSA predicts observers are unlikely to observe large
ages for themselves - it merely predicts that it is unlikely to come
across another observer with a large age.
> - - - - - - -
> Jacques Mallah (jqm1584.domain.name.hidden)
> Graduate Student / Many Worlder / Devil's Advocate
> "I know what no one else knows" - 'Runaway Train', Soul Asylum
> My URL: http://pages.nyu.edu/~jqm1584/
>
>
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Dr. Russell Standish Director
High Performance Computing Support Unit,
University of NSW Phone 9385 6967
Sydney 2052 Fax 9385 6965
Australia R.Standish.domain.name.hidden
Room 2075, Red Centre
http://parallel.hpc.unsw.edu.au/rks
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Received on Wed Oct 06 1999 - 23:25:54 PDT