# Re: White Rabbit vs. Tegmark

On Thu, May 26, 2005 at 07:54:03PM +0100, Patrick Leahy wrote:
>
> * Since the White Rabbit^** argument implicitly assumes a measure, as it
> stands it can't be definitive.
>
> * But the arbitrariness of the measure itself becomes the main argument
> against the everything thesis, since the main claimed benefit of the
> thesis is that it removes arbitrary choices in defining reality.
>
>
>
> ^**  "This is a song about Alice, remember?"  --- Arlo Guthrie
> 

This measure is not arbitrary, but defined by the observer
itself. Every such observer based measure satisfies an Occam's razor
theorem {\em in the framework of the observer}.

I discuss why the arbitrariness of the choice of UTM does not matter
in my "Why Occam's Razor" paper. What I didn't show in that paper (I
wrote it nearly 5 years ago!) was that any mapping of descriptions to
meaning suffices (ie any observer, computational or not) - Turing
completeness is not needed. Turing completeness only gives a guarantee
that the complexities seen by different observers differ by at most a
constant independent of the description.

Cheers

--
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