On Sat, Oct 15, 2011 at 4:39 AM, Craig Weinberg <whatsons...@gmail.com> wrote:

>> Functionalism assumes that the qualia will be reproduced if the
>> observable function of the brain is reproduced. The thought experiment
>> assumes that this is *not* the case. You have therefore missed one of
>> the most basic points.
>
> You are ignoring my point. Function is in the eye of the observer. Do
> you understand that this is true or do you insist that there is an
> absolute reality that is beyond any particular observation?

When we talk about functional replacement it is specific to the
purpose we are considering. The artificial neurons need to reproduce
the electrical activity of the biological neurons they are replacing
in order to stimulate the neighbouring neurons in the same way. The
structure and substance of the artificial neurons is unimportant as
long as this is achieved. It may be that if the structure and
substance is not reproduced the qualia will not be reproduced either,
even though the electrical activity is reproduced. We assume that this
is so and see where it leads.

>> The third person observable behaviour of a Chinese character is the
>> way it reflects the light.
>
> Not true. It could be carved in wood or cast in bronze so that it can
> be read by touching it. There is no difference in the way something
> reflects the light unless there is something that can tell the
> difference.

But if we are just considering the appearance of a Chinese character
the only relevant thing is the way it reflects the light. Who is
interpreting it does not matter: it need only perform the function of
a written Chinese character in the same way as the original Chinese
character.

>> It is not how the character is interpreted.
>> The third person observable behaviour of a neuron is the timing and
>> voltage of the action potential, the type and amount of
>> neurotransmitter released at the synapse, and so on.
>
> Those characteristics are only observable using specific insruments to
> extend the body into the microcosm. When we use different instruments,
> we get different observations. Our subjective experience is just a set
> of observations using different instruments.

The relevant function is what the other neurons see.

>> It is not what
>> qualia are associated with these activities. Are you now clear on what
>> third person person observable behaviour (which usually is just called
>> "behaviour") means?
>
> I am clear that you don't understand what I am talking about.

Replicating the function of an object is not that difficult to
understand. If you have a problem with your car and the mechanic
suggests a replacement with a part that looks different from the
original you ask him if the car will run the same with the new part as
it did before. That's all I mean.

>> > I understand that you think I'm not getting the point that you have to
>> > agree to the thought experiment conditions that include comp, but I do
>> > understand that. You don't understand that I see the problem with this
>> > thought experiment to bother with it. Yes, if functionalism could be
>> > true, then function would be all that is required to do anything, and
>> > if function is all that is required to do anything then anything that
>> > has the same function would have to do everything exactly the same.
>> > It's circular. You could say the same thing with anything. If instead
>> > of comp, we decide to do a thought experiment where we decide that
>> > anything that that casts the same shadow must be the same thing, then
>> > if we make something with the exact same shadow then it must be the
>> > same thing that we have made. It's a fallacy. I can make a volleyball
>> > and call it a soccer ball when it isn't.
>>
>> No, as I have repeatedly said the initial assumption is that comp is
>> wrong, functionalism is wrong.
>
> It's intended to show that assuming that is a problem though.

Yes, the assumption is made that functionalism is wrong and problems
arise that need an explanation. You haven't provided one; my
explanation is that functionalism is right.

>> >> I've repeated this argument several times and you have responded thus:
>> >> - It would be really difficult to make a functionally equivalent brain
>> >> (yes, I agree, but this is a philosophical argument, not an
>> >> engineering project)
>>
>> > Not just difficult, but but potentially impossible, depending on your
>> > definition of equivalent.
>>
>> The artificial brain part is functionally equivalent if the rest of
>> the brain carries on in the usual (third person observable) manner.
>
> It depends entirely on who or what the third person is. You haven't
> figured out yet thateach observer is capable of observing differently
> so that there is no such thing as a quality that is just observable in
> general.

The particular third person observable behaviour of interest is that
the neurons which interface with the artificial replacement are
stimulated in the same way as before. The physical cause of the
neurons firing is therefore replicated. Non-physical influences are
not, but you won't say explicitly that you believe in such influences.

>> >> - A brain can't be functionally equivalent without the qualia (yes,
>> >> this is assumed at the beginning because we are only discussing the
>> >> third person observable behaviour)
>> >> - Qualia are not computable (yes, we assume you are right about this
>> >> at the beginning - otherwise it would be begging the question)
>> >> - Partial zombies as redefined by you can exist (maybe, but you don't
>> >> win debates by redefining terms)
>> >> - A simulation of a thing is not the thing (yes, but the assumption is
>> >> that the simulation just controls the firing of the neurons with which
>> >> it interfaces, not that it is the same as the neurons or has qualia)
>>
>> > The simulation is supposed to replace the neurons. That's what it's
>> > simulating.
>>
>> The simulation interfaces with the other neurons so that their pattern
>> of firing is the same as it would have been before. The simulation by
>> assumption does not reproduce the qualia. It also need not reproduce
>> other aspects of the neurons, such as their mass or colour, unless
>> this is relevant to their interactions with the other neurons.
>>
>
> I'm talking about digital simultion to replace the whole brain, not
> prosthetic additions.

As an engineering problem as well as for the purpose of the thought
experiment, we replace a part at a time and, as with the mechanic and
the car, see whether it works the same. If the subject says they have
gone blind or feel weird or something then the replacement part is not
working properly. If they say they feel normal and they seem to you to
behave normally then the replacement part is working properly.


-- 
Stathis Papaioannou

-- 
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@googlegroups.com.
To unsubscribe from this group, send email to 
everything-list+unsubscr...@googlegroups.com.
For more options, visit this group at 
http://groups.google.com/group/everything-list?hl=en.

Reply via email to