AI and cognitive psychology rant (getting more and more OT - tell me if I should shut up)

[Stephen Horne]

On Sat, 25 Oct 2003 19:03:34 +0100, Robin Becker
<robin at jessikat.fsnet.co.uk> wrote:

>In article <3f8lpvsddmeltg69vkl2uu8u8cei7bb2cg at 4ax.com>, Stephen Horne
><steve at ninereeds.fsnet.co.uk> writes
>>As I already mentioned, if a primitive person observes a car and
>>theorises that there is a demon under the hood, that does not become
>>true. Reality does not care about anyones perceptions as it is not
>>dependent on them in any way - perceptions are functionally dependent
>>on reality, and our perceptions are designed to form a useful model of
>>reality.
>We observe electrons and make up mathematical theories etc etc, but in
>reality little demons are driving them around. :)
>
>Your assertion that there is an objective reality requires proof as
>well. Probably it cannot be proved, but must be made an axiom. The
>scientific method requires falsifiability.

I can't proove it exactly, but I think I can show the alternative to
be logically inconsistent quite simply.

If you assert that there is no objective reality - only perception -
then I have as much right to claim assert my perceptions as anyone
else. And I percieve that there is an objective reality.

>The fact is we cannot perceive well enough to determine reality. The
>physicists say that observation alters the result so if Heisenberg is
>right there is no absolute reality. Perhaps by wishing hard I can get my
>batteries to last longer 1 time in 10^67.

If that were true, why should it only work 1 time in 10^67?

As I said before, the limit of the accuracy of our perceptions is
basically the limit of information processing. *Not* information
theory - we need machinery to do the processing. That machinery has
limits, cannot be perfect, and thus is pretty well optimised to
achieve a purpose as well as possible without the need to be perfect.
The reason it can't percieve quantum effects is because we have no
evolutionary need to percieve things at that level, and thus have no
senses etc etc to deal with them.

Quantum effects are actually a good example, so lets take a look...

Yes, a particle may have two or more states at the same time. But once
*any* observer observes that particle, it resolves to the same state
for *all* observers. Individual observers cannot choose for themselves
what to perceive.

Still, it is worth asking what is so special about this observer. What
makes a particular arrangement of matter special, so that it can
'observe' while other arrangements cannot. Is it some mystic
metaphysical conscience, as many have asserted, or is it perhaps
nothing magical at all, and nothing to do with mind?

I tend to go with Penrose on this. That is, a superposition of states
has strict limits with respect to gravity. Whenever particles are in a
superposition, space-time must also be in a superposition. Particles
therefore have different levels of gravitational energy in each
superposition. This creates an uncertainty in the system. And as
Heisenberg states, a large uncertainty can only exist for a short
time.

Thus the reason why Schrodingers cat cannot be alive and dead at the
same time (at least for more than a tiny fraction of a second) is
because, as with any 'observer', it has a significant mass and
therefore the alive and dead superpositions create too much
uncertainty in spacetime.

Observers are nothing more than large masses that don't stay in
superposition states for significant times, and thus once the observer
(or cat, or for that matter vial of poison) is superposed the whole
system must rapidly resolve to one state or another because of the
scale of uncertainty involved in spacetime.

But it is easier to handle Schrodingers cat that that. According to
the thought experiment, any observation - no matter how indirect -
resolves the state of the system. But at the microscopic scale, that
is simply not the case - superposed particles interact with each other
in ways that allow the superposition of states to be detected, or else
the there could be no experimental proof of superpositions. There is
no such experimental proof at macroscopic scales, thus the same kind
of superposition simply cannot be happening (at perceptible
timescales) at the macroscopic scale.

Just as with relativity, the observer is certainly important but not
defining except in an extremely restricted way. There is a reality
which the observer is observing, and which the observer cannot define
arbitrarily.

Consciousness is not magic. Brains, like the rest of the body, are
just another arrangement of matter - certainly a complex and useful
arrangement, but it is still obeying (not defining) the rules layed
down by the universe we live in. There is nothing special about people
which lets them arbitrarily define the universe.

>Awareness certainly mucks things up in socio-economic systems which are
>also real in some sense. I hear people putting forward the view that
>time is a construct of our minds; does time flow?

Take a look around and you will see that it does. Do you really
arbitrarily choose not to be able to observe next weeks lottery
numbers before you place your bet?

We know that the models provided by physics are imperfect. Maybe some
day someone will explain why time is different to space. Maybe not.
But what we are able to percieve does not define reality - it only
forms an imperfect model.

The fact that perception is not perfect does not mean there isn't a
defining reality to percieve. There must be something that ties all
our perceptions together, though, or else why are they sufficiently
compatible that we can interact at all.

>This is a bit too meta-physical, but then much of modern physics is like
>that. Since much of physics is done by counting events we are in the
>position of the man who having jumped out of the top floor observes that
>all's well after falling past the third floor as falling past floors
>10,9,... etc didn't hurt. We cannot exclude exceptional events.

I'm not excluding the exceptional. I'm also not excluding what I can
see for myself just by opening my eyes.


-- 
Steve Horne

steve at ninereeds dot fsnet dot co dot uk