X-Message-Number: 22395
Date: Wed, 20 Aug 2003 23:27:35 -0700
From: Mike Perry <>
Subject: Isomorphism, Formal Systems

Robert Ettinger, #22384, and my responses

>As to why the simulation cannot be fully isomorphic, I have explained this
>repeatedly too. Any computer system has many features lacking in a brain, and
>conversely. The correspondence cannot be one-to-one.

Consider the following proposition: "One computer (generally) has many 
features lacking in another one, and conversely. Thus a simulation of one 
computer by another cannot be fully isomorphic." Yet we know it can (or can 
be "sufficiently isomorphic" at any rate), that is, one general-purpose 
machine can emulate another one.

>And it might not hurt to repeat the reminder that a computer system can in
>essence be regarded as the realization or embodiment of a formal system, 
>and a
>formal system *never stands alone*--it always requires interpretation in a
>metasystem. The real world stands alone; a computer simulation cannot.

If a theory of everything can be developed, it would seem to indicate that 
reality as a whole can be regarded as a formal system. On the other hand, 
we may ask, really, what is meant by "formal system." Does it imply 
"predictable"? If that is true, then all we need is to equip our computer 
with a quantum random number generator, and it ceases to be a formal system.

Mike Perry

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