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machine brains

Ray Scanlon rscanlon at wsg.net
Sun Feb 21 13:49:08 EST 1999

Eugene Leitl wrote in message <7and36$fcn$1 at mserv2.dl.ac.uk>...
>Michael Edelman writes:
>While a MD level simulation of the brain is no small beer even with
>hitherto hypothetical molecular circuitry, one should point out that
>(short) 1 billion atom MD simulations were feasible in 1995. That's
>not too far from a cubic micron. However, femtoseconds are not

The ability of computer engineers to continually improve on the capabilities
of the digital computer is incredible. But in my opinion, we should lump all
the marvelous molecular happenings in the neuron into a simple electrical
device that uses weighted inputs to produce an output. I, personally, find
this enough. A synaptic junction may be strengthened, how this is done
molecularly is another story.

> > Your model may work for the mechanistic model of mind you propose, one
that has
> > no place for conciousness, but it may not be complete enough to model
aspects of
>'Consciousness' is a high-level description of a large number of
>low-level phenomena. There is nobody else at home.

Consciousness has two aspects: One, objective, is alertness; the other,
subjective, is awareness.

To conjugate:

I am aware.
You are alert.
He exhibits intelligent behavior.

You say you are also aware. I believe you.

In the brain we find alertness, in the soul (mind), awareness. Let us keep
our eye on alertness when we discuss the brain and leave awareness to

> > mind that many of us think are central to the brain's purpose.
>A brain has no purpose. It is an evolved, not a designed structure.

We are moving into the twenty-first century and people must still be
reminded that in a materialistic universe a structure has no purpose.
Purpose belongs to teleology and thus to religion.

>Far enough so that you can't implement it in semiconductor photolitho.
> > What I'm objecting to here is your conception of the brain as a device
with a
> > very predictable, top-down sort of structure. Of course my central issue
here is
> > your rejection of mind, putting you solidly in the
>The word 'mind' is not very meaningful. It smacks too strongly of 'soul'.

Soul (mind) belongs to religion. I would say that most biologists think of a
molecule as a deterministic structure of atoms, Molecules make a neuron,
neurons make a nervous system. May we think of the brain as a deterministic
structure? Why not?

> > your model, and how does it differ from an ordinary computer, apart from
> > size?
>There is no such a thing as an ordinary computer, nowadays. Computers
>control military systems, recognize faces, drive a car from coast to
>coast. With evolvable hardware, there's no telling what they are going
>to be able to do tomorrow.

The wiring, as set up by the DNA, follows a different plan. But if you are
familiar with digital circuitry at the gate level it is possible to get some
carry over. Of particular use is a good knowledge of the interplay between
positive and negative logic. Neurons elsewhere activate neurons in the
reticular nucleus of the thalamus. These, in turn. inhibit neurons in the
thalamus, thus halting the flow of signal energy on its way to the neocortex
and also halting motor programs form the basal ganglia and the cerebellum on
their way to the motor and pre-motor cortex. The relationship between
activation and inhibition on the one hand and positive and negative logic on
the other and is fruitful.

If your only knowledge of a computer is through a GUI (graphical user
interface) there is no way for you to make the jump.

> > To equate soul and mind is to claim questions about mind are
metaphysical ones-
> > but they're not. One can investigate the nature of conciousness through
> > controlled and repeatable experiments. You can't do that with the soul.

The word "mind" is only a euphemism for "soul". It is for the use of people
who are too nice to say "soul" in mixed company. One may investigate
alertness through experiment. Awareness is for religion.

> > You'll never explain brain without explaining mind.
>Uh, isn't this the other way round?

That's the way I look at it. Except I should be satisfied if I could explain
brain. Let others take on the soul (mind).

Those interested in how the brain works might look at

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