[extropy-chat] Death is irreversible v.1.0

[Eric Messick]

Heartland:
>Okay, I see what you were getting at. I think that the stuff that mind is made of 
>looks more like electrons than neurons. And if we dig to the bottom of it, it is 
>energy. (I refrained from using energy in the argument to avoid any more confusion, 
>but, ultimately, a true argument should use energy.)

and:

>"Nervous system" is a superset of "mind object."

Good.  That makes sense to me.

Mitochondria (among other things) within neurons are part of the
support structure for the neuron, but are not fundamental to the
process of producing mind.  If the mind is running on a different type
of substrate there may be no mitochondria.  A silicon computer
simulating a neuron need not include such support structures if the
simulation is of mind operations rather than metabolic functions.

My understanding is that the important pieces of activity are the
following:

Electrical impulses polarize the cellular membrane (change the
relative electrical potential of the inside versus the outside).

Polarization affects the shape of ion channels in the membrane
allowing charged particles to diffuse through the channels.  That
diffusion maintains and propagates electrical impulses.

When an electrical impulse reaches a synapse, the altered polarization
causes conformational changes to molecules embedded in the cell wall,
resulting in the release of neurotransmitters into the synaptic gap.

The neurotransmitters diffuse across the synaptic gap to the another
neuron, where they bind to receptor molecules on the outer surface of
the cellular membrane.  Those molecules change their conformation in
response to binding the neurotransmitter.  That conformational change
extends to the interior of the post-synaptic neuron where it activates
enzymes which perform chemical reactions within the cell.

Those reactions change the concentration of various chemicals within
the post-synaptic neuron.  The concentrations control various
functions within the cell.

The cell may become more or less likely to fire an electrical impulse
as a result of the change in concentration.  The cell may become more
susceptible to firing in the future.  The cell may manufacture more
receptors to strengthen the synaptic connection.  The cell may begin
growing new dendrites which can form new connections with other
neurons.

These changes occur at various time scales, and control processes that
occur at similar time scales.  Single electrical impulses can
propagate from one neuron to another on the order of milliseconds.
Changes in the synaptic strength can last for minutes or hours, and
result in the formation of active memories.  Permanent changes in
synaptic strength, or the number of synapses result in long term
memories.

In addition to the release of neurotransmitters affecting cells across
a synaptic gap, neurotransmitters and other hormones can diffuse
through the brain and change the behavior of larger numbers of neurons
in a much less localized manner. 

So, the crucial pieces of information are:

What are the physical locations of all of the synapses and the neural
cell walls that connect them?  This is needed to deal with diffuse
neurotransmitters.

What neurons connect to what other neurons?  What are the type and
strength of all of the synapses in each of those connections?  This is
necessary to deal with the propagation of electrical impulses.

What are the concentrations and concentration gradients of the active
chemicals within and around each neuron?  This is necessary to model
the chemical changes which mediate the slower changes in the neurons.

These are the things which have to be included in a "mind object".

Heartland:
>>>It is not possible to merge two different minds into one instance, because the
>>>merger process would inevitably reach a "critical" point when one mind would be
>>>forced to "switch off/sacrifice" its own instance of subjective experience for
>>>another.

Eric:
>> That depends on how the merger process takes place.  Again, you're
>> trying to describe a grey area with a binary distinction.  It just
>> doesn't work.

Heartland:
>Why?

Because the merger process can be gradual.  If you pour a bucket of
red paint and a bucket of blue paint into a third bucket, at some
point you end up with a bucket of purple paint.  When was there no
longer a bucket of red paint?

Heartland:
>Only *information about an activity* can be encoded in information, not that 
>activity *itself.*

Yes.  Activity is embodied in matter in motion.  Matter can be set
into motion based on information.  Information can be generated based
on the activity of matter.

The two are equivalent ways of looking at the same system.

I think you may not accept the above statement.  I think it is the key
to why people are disagreeing with you.  We record and reproduce
activity all the time, but not yet at the fidelity necessary to
reproduce mind.  Can you accept that we will be able to do that?

Heartland:
>What actually happened was that all the energy that powered that activity has 
>dissipated, causing irreversible end of an instance.

No!  The energy is not all dissipated.  The kinetic energy has mostly
(but not totally) dissipated.  There remains a significant amount of
potential energy.  How do we know this?  It took energy -- metabolism
-- to construct the cells of the brain.  That energy is still there.
A brain is at a higher potential energy than a cloud of Carbon,
Hydrogen, Oxygen, and Nitrogen atoms.  They're held together by the
molecular binding energy of the bonds between the atoms.

And, there's information content in those bonds.  They tell how the
brain would have reacted to a stimulus while it was alive.

Eric:
>> For a while it was stopped.  So what?

Heartland:
>You will remain dead forever.

Not if we can restart the activity.  The instance retains it's
identity as long as the information encoding the mind can still be
used to reconstruct the mind.

>Thanks for the feedback, Eric.

No problem.

-eric