From newshub.ccs.yorku.ca!ists!helios.physics.utoronto.ca!news-server.ecf!utgpu!cs.utexas.edu!uunet!psinntp!scylla!daryl Thu Feb 20 15:22:22 EST 1992
Article 3893 of comp.ai.philosophy:
Newsgroups: comp.ai.philosophy
Path: newshub.ccs.yorku.ca!ists!helios.physics.utoronto.ca!news-server.ecf!utgpu!cs.utexas.edu!uunet!psinntp!scylla!daryl
>From: daryl@oracorp.com
Subject: Re: Virtual Person?
Message-ID: <1992Feb20.034428.8083@oracorp.com>
Organization: ORA Corporation
Date: Thu, 20 Feb 1992 03:44:28 GMT

Joseph O'Rourke writes:

> Long long ago, I asked if Searle had responded to the idea of
> replacing neurons by functionally-equivalent silicon chips.  My point
> was that this can be used as an intuition pump for the implications of
> Searle's position: a functionally equivalent silicon brain does not
> "understand" etc.  David Chalmers responded, yes, and in fact the
> intuition pump can itself be pumped by imagining the silicon
> replacement neuron by neuron, which would imply by Searle's position,
> that qualia would either have to fade or switch off at some point, and
> either alternative is implausible.  Jeff Dalton asked what's so
> implausible with fading qualia/consciousness?  And I concurred: David
> Chalmers pump of the pump does nothing for me. If
> functionally-equivalent silicon neurons don't have the mental magic
> for some reason, one would expect the qualia to fade.

This summary left out David Chalmer's argument why the qualia
*wouldn't* fade. If I understand it correctly, it goes as follows: if
a person's qualia started fading, (as you put it, perhaps colors start
seeming less intense), doesn't it make sense that this fading would
affect the person's *functioning*? That is, wouldn't you expect the
person to think: "Hey, colors don't seem as intense as they used to!"
However, by hypothesis, the functional properties of the person do
*not* change when neurons are replaced by silicon.

In other words, Chalmers is not saying 

     Fading qualia is impossible

he is saying:

    Fading qualia would imply a change in the functioning of the person.

Daryl McCullough
ORA Corp.
Ithaca, NY


  





