Re: Category Theory and Rosen - some clarifications (i hope 8-))

[glen e. p. ropella]

Barry McMullin writes:
 > I didn't say the stuff/goo/whatever had to have a "fixed
 > organisation"; I said it had to have a fixed "composition": that
 > is, *which* goo belonged to or composed the "system" was fixed
 > (howsoever "goo" might be defined in context).  The "organisation"
 > (state) of the goo could still be changing all the time...

Hmmmm.  Now I'm lost again.  You seem to be implying that the system
is made up of pieces that have identity in some way.  The phrase
"which goo belonged to" is nonsensical (irregardless of the impact of
the word "goo").

Since you can use the phrase "which goo belonged to or composed the
'system'" implies that some of the goo can be distinguished from other
goo.  This distinguishability is not possible, unless you assume some
substrate of material or particle or, even, convolved energy, or
somesuch.  And to specify that one part of the goo is distinguishable
from another *is* to say that it has an organization.

Invariant composition necessarily implies an invariant (or at least
finite possibilities of) organization at *some* level.  Neither the
converse nor the contrapositive are true.  I.e. Invariant organization
does not necessarily imply invariant composition.  And variant
organization does not necessarily imply variant composition.

For example, we can put together a system of particles in several
different ways without varying the particles themselves, which gives
us variant organization and invariant composition.  But, the
organization(s) used to plug those particles together is not infinite.

But, you are arguing for *variable* composition where I'm arguing for
*arbitrary* composition.... I.e. my case includes your case because
not only can the type and amount of the composite pieces of my goo
change, but the fact that they are pieces at all can change (e.g. a
pi-meson can decay into a muon and another pion at any time).

Again, since there is no bottom turtle, we can't really talk about the
finest fidelity of composition.  The composition is arbitrary.

 > OK, I was (semi-deliberately) using "system" in a loose sense.  This
 > was intended to resonate with the fact that, colloquially, people -
 > even scientists - do use the s-word for things (like gliders) that
 > are not "systems" in certain technical senses (e.g. dynamical "systems").
 > 
 > We can call them "objects" if you like. Of course, we'd better admit that
 > this is the informal, loose, sense of "object", not, for example, the 
 > technical,
 > computer science sense, as in "Object Oriented Programming" ... the latter
 > "objects" would be perfectly good "systems" in the previous sense.  

Agreed.

 > Yup, that's where I'm at (albeit wary of a creeping inductivism)...

I don't think there's really anything "creeping" about this.  It is at
least analogous to induction, if not synonymous with it.  But, if we
don't allow induction, then we're in trouble.  What we need to avoid
is inappropriate generalization.

 > > Now, don't get me wrong, gliders *do* exist.  They just don't exist
 > > *inside* the GoL.  They are a part of the larger system that consists
 > > of the CA, the visualization mechanism, the computer, and the person
 > > who identifies ... or "objectifies" the glider.  So, in order to ask
 > > causality questions about the behavior of the glider, we have to,
 > > basically, provide more complete entailment of the CA by "wrapping"
 > > it in a larger system.  When we do that, we can say things about the
 > > meta-system.  For example, "The glider is there because the CA has
 > > these rules, this initial state, this mechanism for affecting the
 > > computer screen, and because I tried several different combinations
 > > until I got something that I could identify."
 > 
 > Yikes!
 > 
 > Do I hear the muffled sound of a glider crashing into a tree
 > in the forest, with nobody around to see?
 > 
 > Do you really mean to say that the gliders are not there unless the
 > state of the Life world is being projected on a monitor (in the
 > "usual" projection) *and* some person ("sentient observer"?) is
 > watching?

No.  What I mean to say is that gliders do not exist in the context of
the CA.  They only exist in the context of the system of which the CA
is a part.  Gliders are meta-CA objects.

And if the human didn't exist, then the computer wouldn't exist and
the visualization mechanism wouldn't exist and, therefore, the glider
wouldn't exist.  However, if the human exists at time t0, the computer
at time t1, the visualization mechanism at time t2, and the CA at time
t3, then the glider would certainly exist at time t4.  This is an
imprecise way of stating that the system is not really time-dependent.
But it is causally dependent.

This is fundamentally different from the "God is in the Quad" problem
because the glider is artificial/synthetic/man-made.

 > Absolutely.  But as you can see, I don't (yet) buy the idea as you
 > seem to be suggesting it.  But we are definitely getting closer!

I'm *extrememly* glad to hear that we're getting closer. [grin] The
relationship between this recent stuff and "modeling" may seem
tenuous; but, in my oh-so-humble opinion, could end up being critical.
But, then again, I *like* philosophy.

glen
-- 
{glen e. p. ropella <address@hidden> |  Send lawyers, guns, and money!  }
{Hive Drone, SFI Swarm Project         |            Hail Eris!            }
{http://www.trail.com/~gepr/home.html  |               =><=               }


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