Re: computationalism and supervenience

From: David Nyman <david.nyman.domain.name.hidden>
Date: Mon, 04 Sep 2006 07:57:48 -0700

Bruno Marchal wrote:

> Either those *specific* physical activities are turing emulable, and we
> are back to "1)" and "2)", or they are not, and then comp is false.
> Recall we assume comp.

I don't follow. I thought Maudlin is proposing a physical machine
running the consciousness program, not a turing-emulated one. Are you
saying that if we assume comp, the 'physical activity level' of a
correctly substituted emulation is posited as equivalent to that of a
'real' machine (i.e. there is in fact no meaningful distinction)? In
this case AFAICS the substitution level would need to be below that of
'registers' etc, which are insufficiently constrained aspects of
machine architecture.

> We would have zombie. Why not. Once comp is false ...

Why talk of zombies? A zombie is a being that is supposedly conceivable
(though not to me) as being 'unconscious' despite apparently possessing
the structural/ behavioural prerequisites of consciousness. I was
referring to the issue that, if the characteristics of consciousness
are indeed correlated with specific physical activities, then aspects
of consciousness would necessarily *co-vary* with physical
instantiation. To avoid this, comp would need to adopt a substitution
level that preserved the invariance of whatever 'physical activities'
were deemed relevant to consciousness (as I suggest above).

> OK in this situation. But comp makes impossible to distinguish the
> experience of driving a car, and the experience of driving a virtual
> car in a virtual environment, done at the right level of substitution
> (or below). Then the movie-graph or Maudlin's Olympia shows that
> machines cannot even distinguish a physical virtual environment and a
> purely arithmetical virtual environment.

So this is all about the level of substitution. Well, as I've
suggested, I think the level would have to be at or below that at which
machine architecture differences become indistinguishable. So I don't
believe that arguments involving registers etc. can be correct, because
it becomes hard to argue coherently that the necessary invariances are
preserved at this level. We might debate atom-by-atom, or
circuit-by-circuit, or does the doctor have some more general principle
to resolve this?

BTW I think I see now that most of our original disagreements were
language based. If comp is in essence an objective idealist model, in
effect it begins from the assumption that 'objective idealist reality'
exists 'in the sense that I exist' (although of course not constrained
solipsistically to my 1st-person pov). That is all I have ever sought
in terms of '1st-person primacy'.

David

> Le 03-sept.-06, à 17:18, David Nyman a écrit :
>
> >
> > Bruno Marchal wrote:
> >
> >> Maudlin build first a digital machine, let us call it M, which do a
> >> computation PI (Maudlin's name for it) which we suppose does
> >> correspond
> >> to a genuine consciousness experience (for example some remembering of
> >> the taste of cocoa).
> >
> > At this point we don't know whether the conscious experience is
> > supposed to:
> >
> > 1) inhere in the computation independent of physical instantiation
> > or
> > 2) inhere in some subset of the physical activity of the machine that
> > is supposed to be 'relevant' for the computation
> >
> > It seems that what is intended under 2) must be *any* physical activity
> > that could be construed as 'implementing' this computation, since
> > syntactically equivalent hardwares aren't constrained to any particular
> > set of physical activities.
>
>
>
> All right.
>
>
>
> >
> >> Suppose that during the running of that particular computation PI, the
> >> register r1, ...r67 are never used. Maudlin argue that if
> >> consciousness
> >> is attached to the physical activity relevant for the computation, we
> >> can retrieve those unused part of the computer, without changing the
> >> consciousness experience.
> >
> > OK, under either assumption 1) or 2) above.
> >
> >> He shows then that he can managed to build a version of M,
> >> proto-olympia (say) which has almost no physical activity at all when
> >> he follows the PI computation.
> >
> > But this will only preserve the conscious experience under the prior
> > assumption of its invariance to physical activity.
>
>
> Yes. OK.
>
>
>
> > If this invariance
> > is false we have a third possibility:
> >
> > 3) consciousness inheres in *specific* physical activities (and
> > consequently physically-instantiated comp is merely 'syntactic
> > simulation')
>
>
> Either those *specific* physical activities are turing emulable, and we
> are back to "1)" and "2)", or they are not, and then comp is false.
> Recall we assume comp.
>
>
> >
> > Under this assumption, changing the physical details of the
> > implementation might have any arbitrary effect whatsoever on the
> > original conscious experience.
> >
> >> Proto-olympia is *physically* accidentally correct for PI, but no
> >> more
> >> counterfactually correct.
> >
> > We don't know what effect the lack of counterfactuality would have on
> > the conscious experience. None, if 3) is correct.
>
> All right (but comp need to be false).
>
>
> >
> >> Then Maudlin reintroduces the unused parts, the Klaras, which
> >> reintroduces the counterfactual correctness, WITHOUT ADDING any comp
> >> relevant physical activity (if not, it would mean the level is
> >> incorrect(*)).
> >
> > Again, under 3) this wouldn't affect the conscious experience if the
> > relevant physical invariance is preserved.
> >
> > So comp + physical supervenience (phys-sup) would force
> >> us to associate any consciousness experience to any physical
> >> processes.
> >
> > Under 3) it would force us to associate specific conscious experiences
> > to specific physical processes, at the correct (physical) substitution
> > level.
> >
> >> And that would kill comp! So sup-phys -> NOT comp, or equivalently
> >> comp
> >> -> NOT sup-phys.
> >
> > Under 3) it would kill comp as a theory of the invariance of
> > consciousness to physical activity.
>
>
> Sure.
>
>
>
> > It would be possible for a physical
> > process that was conscious to be turing-emulable, but for the conscious
> > experience to be non-invariant to different instantiations of such
> > emulation.
>
> We would have zombie. Why not. Once comp is false ...
>
>
> > This would follow from the inherence of consciousness in
> > *specific* physical activities. I'm speaking here of comp as
> > instantiated in a *physical* machine, and consequently this is no
> > different to the claim that you can't drive a comp-emulated car down to
> > the shops (at least not the ones *outside* of the machine). The car you
> > need for your trip is non-invariant to turing-emulation.
> >
> > This is essentially the point I attempted to establish in my original
> > 'anti-roadmap' post. Assumption 3 claims that 'conscious' activity must
> > inhere in specific causal sequences seamlessly spanning the machine and
> > the world outside it. Without this, it is difficult to see how
> > 'consciousness' could be causally relevant to the intentional
> > interaction of the machine with its environment.
> >
> > As conscious machines ourselves we understand very well the difference
> > between the car we dream of (the 'emulated' Ferrari) and the one we
> > actually drive (the VW we causally interact with).
>
>
> OK in this situation. But comp makes impossible to distinguish the
> experience of driving a car, and the experience of driving a virtual
> car in a virtual environment, done at the right level of substitution
> (or below). Then the movie-graph or Maudlin's Olympia shows that
> machines cannot even distinguish a physical virtual environment and a
> purely arithmetical virtual environment.
>
> Bruno
>
>
> http://iridia.ulb.ac.be/~marchal/


--~--~---------~--~----~------------~-------~--~----~
You received this message because you are subscribed to the Google Groups "Everything List" group.
To post to this group, send email to everything-list.domain.name.hidden
To unsubscribe from this group, send email to everything-list-unsubscribe.domain.name.hidden
For more options, visit this group at http://groups.google.com/group/everything-list
-~----------~----~----~----~------~----~------~--~---
Received on Mon Sep 04 2006 - 10:59:40 PDT

This archive was generated by hypermail 2.3.0 : Fri Feb 16 2018 - 13:20:12 PST