Re: Questions on Russell's "Why Occam" paper

From: Russell Standish <>
Date: Tue, 7 Jun 2005 17:20:44 +1000

On Tue, Jun 07, 2005 at 08:29:57AM +0200, Bruno Marchal wrote:
> Le 06-juin-05, ? 22:51, Hal Finney a ?crit :
> >I share most of Paddy Leahy's concerns and areas of confusion with
> >regard to the "Why Occam" discussion so far. I really don't understand
> >what it means to explain appearances rather than reality.
> Well this I understand. I would even argue that Everett gives an
> example by providing an explanation of the appearance of a wave
> collapse from the SWE (Schroedinger Wave equation) and this without any
> *real*collapse.
> And I pretend at least that if comp is correct, then the SWE as an
> *appearance* emerges statistically from the "interference" of all
> computations as seen from some inner point of view of the mean
> universal machine.
> But, as I pointed a long time ago Russell is hiding (de facto, not
> intentionally I guess :) many assumptions.

It would be nice to expose these "hidden" assumptions. As far as I'm
aware, all my assumptions are exposed and upfront, where at least you
as a reader can decide if you agree, but there is always the
possibility of some that I've missed.

> There are a lot of "derivation" of the SWE in the literature, it would
> be interesting that Russell compares them with its own. My favorite one
> is the one by Henry and another one by Hardy.

The only thing I was aware of by Henry was a derivation of the
correspondence principle from gauge invariance in a paper you sent me,
something I think that Stenger does better in his book (which is
almost published now!).

And as for Hardy, I never found his axioms terribly "reasonable",

> Note the incredible derivation of QM from just 5 experiments + a
> natural principle of simplicity by Julian Swinger in his QM course
> (taken again by Towsend in its QM textbook). I will give reference once
> less busy.

Sure - I'm not aware of that.
> I agree with Hal and Paddy about the lack of clarity in many passages.
> Note that my result is infinitely more modest (despite the
> appearance!).

Hardly infinitely more modest. You start from a slightly different
basis (COMP thesis vs all descriptions ensemble), derive the
existence of what I assume, and end up not quite where I end
up. Perhaps if you adopted Kolmogorov probability axioms, you could
get the full QM theory to result. The other things I assume tend to be
assumed by you also - COMP => TIME, and I think you assume PROJ. Not
sure where your work stand with the Anthropic Principle.

> I just prove that if comp is assumed to be correct then a
> derivation of the SWE *must* exist, without providing it. Well, in the
> interview of the Lobian machine I do extract some 'quantum logic' from
> comp, but it is too early to judge if the SWE can be extracted from it.
> But it should be, in principle, if comp is true. Advantage: I just
> assume natural numbers and classical logic, I don't assume any geometry
> or temporality, which for me are really the miraculous things in need
> to be explained.
> Bruno

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Received on Tue Jun 07 2005 - 04:25:28 PDT

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