RE: What We Can Know About the World

From: Hal Finney <hal.domain.name.hidden>
Date: Sat, 30 Jul 2005 23:25:07 -0700 (PDT)

Jesse Mazer writes:
> as I said, my idea is
> that *all* possible causal patterns qualify as "observer-moments", not just
> complex ones like ours. And I don't disagree that complex observer-moments
> are generally the result of a long process of evolution in the physical
> universe, it's just that I think at a most fundamental level the "physical
> universe" would be reducible to an enormous pattern of causal relationships
> which can be broken down into the relationships between a lot of
> sub-patterns, each of which is an observer-moment. The idea that physics
> should ultimately be explainable in terms of nothing more than causal
> relationships between events, and that higher-order concepts like
> "particles" and "spacetime" would emerge from this level of explanation, is
> an idea that some approaches to quantum gravity seem to favor, like loop
> quantum gravity--it's at least not out of the question that a final
> "physical" ToE would be about nothing more than causal relationships between
> events. If so, it would just be a different "interpretation" of this theory
> to say that each sub-network in this universal causal network would be an
> observer-moment of some kind, and my "meta-physical" speculation would be
> that you could *start* by looking at all possible finite causal networks and
> finding a unique measure on them, and the appearance of the huge causal
> network we call the "physical universe" could be derived from the
> relationships between all the sub-patterns implied by this unique measure.

This is a very interesting speculation which raises some random questions
and comments:

1. One problem I have is with the notion of causality. Do you view this as
something that is well defined, the degree and/or kind of causality that
one node in a causal network applies to another? Would it be merely a
boolean (node A either does or does not have a causal influence on node
B) or would it be more complex (node A promotes B while inhibiting C)?
I realize that these are detailed questions to be asked of an embryonic
theory but it would help to understand what your notion of causality is.

One of my concerns is that some universes may not have causality as well
defined as ours does, and I wonder how well your theory would work there.
In fact, even in our universe one can certainly imagine situations and
relationships between events where the existence or degree of causality
is not at all well defined. I'm worried about basing a model for
consciousness on something as abstract and ill defined as causality.
Are we replacing one mystery with another?

2. If we think of the "causal pattern" which corresponds to a conventional
observer-moment, say your experience of eating a particular bite of cherry
pie, would you imagine that this is something which could in principle
be diagrammed, and/or represented in some kind of canonical form?
So we could point to this picture and say, this *is* that particular
experience of eating that byte of cherry pie. That would be pretty
cool, and I do think that ultimately any theory of consciousness is
going to have to be able to do something like this.

3. Presumably the actual causal patterns of our conscious moments are
very large. We have trillions of neurons each with tens of thousands
of synapses, firing at hundreds or thousands of times per second.
That's a lot of activity, all of it intricately linked into what might
well be called a causal network, although the "causality" involved is
quite complex and involves integration over time. But assuming that we
could in fact imagine representing that in canonical form, clearly the
representation would be very large.

We could imagine successively simpler "causal patterns" until we got
down to quite trivial ones. Calling them "observer moments" seems to
be a bit of a stretch, given the enormous number of orders of magnitude
difference between what we would normally recognize as a conscious OM and
one of these trivial ones. But on the other hand I agree that we could
probably not draw a line in this succession of causal patterns and say
this half are conscious, this half are unconscious. Presumably we are
talking about shades of gray here, degrees of consciousness. It never
completely goes away, although it certainly gets close enough to zero
for all practical purposes.

4. Another point is that for a "causal pattern" to actually be
recognizably conscious requires more than complexity. One can imagine
any number of causal networks of perhaps tremendous complexity that would
not seem particularly likely to correspond to what we would recognize
as conscious experience. (In terms of the "shades of gray" analogy,
even though the networks are at least slightly conscious by definition,
there would still be virtually no "gray" there.)

5. To me, this points to the problem with panpsychism theories like this.
On the one hand, everything is conscious (at least a little bit).
This saves us from the Sorites paradox, that it's impossible to draw a
line among shades of gray and try to separate white from black. But on
the other hand, in practice only brains are noticeably conscious (and
probably only big brains; the nematode with its 302 neurons can't have
much consciousness). Even though our stomachs and earlobes are causal
networks and have their little slivers of consciousness, only our brains
manage to really count. It just seems strange that if consciousness is,
in the metaphysical sense, so easy that it's omnipresent, then why do
so few systems actually exhibit it?

Hal Finney
Received on Sun Jul 31 2005 - 03:18:08 PDT