re:valuable errors

From: Marchal <marchal.domain.name.hidden>
Date: Wed Apr 21 03:01:49 1999

Gilles Henri:
>What I'd like to stress is that even if infinite computing is a "practical"
>possibility (the word "practical" should be carefully defined in that
>context), it would not realize a duplication of an individual being in the
>same world, but rather a duplication of the entire Universe. So it is
>conceptually different of the COMP hypothesis of Bruno, which applies to
>the generation of "clones" of yourself, who could eventually replace you.

Perhaps I should insist that the comp hypothesis, as I conceive it, does
not
put any restriction on the level of substitution.
Comp is still correct if the correct description of my brain is given by
the complete quantum state of the "universe" (the multiverse).
It is true that, for the sake of simplicity, I assume much more in the
thought experiments ... until the introduction of the Universal
Dovetailer. At that stage I need only the hypothesis that the state of my
brain (which can be the state of the "whole universe") is
turing-accessible.
BTW, if comp is correct, no machines will ever been able to determine her
level of substitution. A machine can only bet on such a level.

>In summary I think that:
>
>You ----> (You 1 + you2 in the same Universe) is impossible (in my
> sense!).
>
>You in Universe 0 ---> You 1 in Universe 1 + You 2 in Universe 2
>
>is admittedly possible, but requires a careful definition of what allows to
>consider "You1" and You2" as two copies of the same "You". In MWI it is
>because "You1" and "You2" are both related to "You" by a spatio-temporal
>continuity, which applies to all macroscopic (not only conscious!) objects
>and which allows under some "classicity" conditions to order different
>macroscopic Universes along a temporal order.

If you appeal to "spatio-temporal" continuity here, you are begging the
question. Only if comp is false can such an argument be use to define a
non
computational -may be correct, but outside the scope of my working
hypothesis- definition of identity.

>So if you think you could reproduce a human being (in Bruno's sense, that
>is an exact copy that you could consider as another version of yourself),
>for example with a silicium-based computer, tell me please how you would
>implement these functionalities:
>* taste a new meal and tell if it tastes good or not.
>* experiment a new narcotic
>* react to a new virus
>* meet a girl(boy) and try to charm her(him) , (all these being still
>unknown when you build it!).
>
>I need very good argument to think it is feasible without duplicating our
>physical structure, or to convince me that all this is not essential to our
>"humanity".

It all depend of what you mean by "physical structure", which I take to
be a
kind of modern "phlogiston".
Taste, charm and things like that are, without doubt, essential to our
humanity. But we don't need to be able to implement these for
*postulating*
comp true.

To sum up, the only way to "refute" the computationalist postulate is to
derive physics from comp and to show that this physics is essentially
different from our empirical physics. And of course this will not give a
logical refutation of comp, but this will give sort of empirical evidence
against it.
For exemple if quantum computer would have been refuting Church Thesis,
then indeed comp would have been shown to be *perhaps* false. But Quantum
Computers haven't refute Church Thesis ...

The main problem here is to understand our motivation, I mean the
motivation
 of those who are searching for a *theory of everything*.
I do not accept a theory of everything which put the "problem of
consciousness" under the rug. And once you mind seriously the
consciousness
 problem with comp, you eventually realise that it is much more easy to
explain where our beliefs in "physical structures" come from than to
explain
 how a *subjective* belief can be *attached" to anything *material*.

Gilles, you said elsewhere in this discussion that you don't take
the physical laws for granted. But if you base an identity criterion on
things like "physical continuity" you will enter into a loop...

A+ Bruno.
Received on Wed Apr 21 1999 - 03:01:49 PDT