The questions to ask, is whether a digital computer
can duplicate enough of the function of the brain,
to allow it to make a robot, act like an intelligent
human, and whether "acting" like a human, would make
it conscious and give it a mind.

Hi
[...]
So my question is, what scientific evidence is there that every neuron
type present in the human nervous system is a digital computer ?
[...]

It seems to me that the question of wether the brain (and therefore the
mind, as a subproduct of activity of the brain inside a body) is a
digital computer can be reduced in principle to the question of weather
the neuron is a digital computer (or turing machine or Von newmann
machine) since if this was true, than each neuron could (in principle)
be substituted by a digital (nano)computer until all neurons were
substituted and you ended up with a digital computer brain.

Miguel Negrao wrote:
Hi
[...]
So my question is, what scientific evidence is there that every neuron
type present in the human nervous system is a digital computer ?
[...]

None.

In fact I don't know of any evidence that any neurons are digital
computers.

cheers,
Wolf k.

And regarding digital physics, it's an interesting concept but there's
no evidence to support it whatsoever.

Miguel Negrao wrote:

And regarding digital physics, it's an interesting concept but
there's no evidence to support it whatsoever.

The discreteness of quantum physics and physical reversibility are
weak evidence in favour, IMO. There's very little evidence in either
direction - and there may not be until we know more about what the
laws of physics are.

Now, as far as I understand the concept of computable regards discrete
systems. So to ask something like wether a pendulum is computable
doesn't seem to make any sense because the system is not even discrete

If this is correct, then since most systems are obvisouly continuous

prove the the neuron is a digital computer it would first have to be
established that it operates as a discrete system.

It seems to me that the question of wether the brain (and therefore the
mind, as a subproduct of activity of the brain inside a body)

where did you get that idea ? an atom can move in any direction in 3D
world continously, there is nothing digital about that !

On Jul 17, 3:30=A0pm, c... at (no spam) kcwc.com (Curt Welch) wrote:

The questions to ask, is whether a digital computer
can duplicate enough of the function of the brain,
to allow it to make a robot, act like an intelligent
human, and whether "acting" like a human, would make
it conscious and give it a mind.

There are two views of what is happening. One is the
program that describes what is happening to it and the
other is the external observer that describes what is
happening when the program runs.

The program may have no representation of its logic
gates and other low level processes just as we have
no representation our neurons or low level processes.

The contents of "our mind" are those representations
which are both spatial and temporal in nature, even if
some people like to narrow their view to the temporal,
that make up our descriptions of what is happening
to us.

The duality is not in the reality of what is there but
in the two views being referenced. They are two views
of the same thing but represented in different ways.

JC

Miguel Negrao wrote:

Now, as far as I understand the concept of computable regards discrete
systems. So to ask something like wether a pendulum is computable
doesn't seem to make any sense because the system is not even discrete

Unless digital physics is true, and there is little evidence against it.

If this is correct, then since most systems are obvisouly continuous

Unless digital physics is true, and there is little evidence against it.

prove the the neuron is a digital computer it would first have to be
established that it operates as a discrete system.

It doesn't much matter. The more practical question is whether it can
be closely approximated by a digital system. There, we can invoke
Church and Turing.

I've never seen any argument to suggest that time or space was digital in
any real sense.

There is nothing about the universe or the brain that gives us freedom to
argue that it's functionally isomorphic to a digital computer - which is
nothing but a finite state machine.

If there are some views of the universe in physics that can make that
argument, then the number of states in even a single neuron so vastly
larger than what we could every hope to emulate in any computer, then it's
not relevant to pretend that there's a meaningfully similarity.

The question we are trying to answer is is whether digital hardware (that
WE CAN BUILD ONE DAY FOR A REASONABLE ABOUT OF MONEY) can duplicate the
functional properties of a human brain that is the foundation of all the
behaviors we humans currently are able to use for our survival, but which
we have not yet been able to duplicate in our computer hardware. If the
only answer is to build a computer that is larger than a million galaxies
combined simply to duplicate all the physical states of a single neuron,
then the point is absurd to even talk about.

You have to model physics somehow. Discrete models
are no more based on unproven assumptions than
continuous models are.

Curt Welch wrote:

I've never seen any argument to suggest that time or space was digital
in any real sense.

That is easily corrected:

http://en.wikipedia.org/wiki/Digital_physics
http://www.digitalphilosophy.org/Home/Papers/tabid/61/Default.aspx
http://en.wikipedia.org/wiki/Simulism