>Hence, practical "reality," that is, anything we are able to study through
>the senses, cannot be separated from models.
This fits very well into the concept of pragmatism that I try to
defend. In my discussion with Don I used the word "reality" as a
substutute for an "ultimate model" no matter if it exists or not.
For me it was important to show that we can talk about "mechanisms"
and "non-mechanisms" only in application to models. As a result,
the notion of reality is no longer interesting, which was the purpose
of my arguments.
What you call "practical reality" is not something independent from
our thoughts (what people usually think of reality). Instread,
"practical reality" is a result of our activity that follows specific
models that humans have developed in their biological and cultural
evolution. We consider objects mechanisms if our behavior directed
to these objects is simple. For example, a slave-owner may treat
slaves as mechanisms. Thus, being a "mechanism" is not a property
of an object but a property of our interaction with that object.
>Our reference to something "real" in a practical sense, by this reasoning
>MUST involve some kind of model, and therefore MUST involve the concept of
>level or scale, which is inherent in our definition of "things" or
>"entities."
I agree that the notion of scale is very important and that some
objects will simply dissolve when viewed at a different scale.
It seems that scale is not a part of the model but it corresponds
to the kind of interaction with an object. For each scale we may
develop a specific model that represents best our interactions at
that scale.
>Here I consider two options:
>
>a) It is only simple because we look at it through a simple model. If we
>looked at it as a complex thing, then it is complex;
>
>(b) It IS functionally simple because we MUST identify "it" before we can
>contemplate "it," and thus the "it" refers to a specific scale and level of
>practical reality that in every observation/interaction we or anything else
>can make, is predictably and repeatably simple. It is not a matter of more
>precise measurements revealing complexity, because at the level at which
>this would occur (for an inanimate object), the "it" we are referencing no
>longer exists. "It" is a macroscopic "it" defined only in terms of our
>interaction with it at the macroscopic level. At the level where "it" is
>complex, "it" is no longer "it" and we are no longer obtaining knowledge
>about "it."
>Indeed, the level at which a car becomes complex is a level
>where the concept of "object" itself no longer applies.
My impression is that we can talk about a car even at a molecular level.
Of course it will not function as a car, but it does not matter
because we look at the complexity of an object and not at its
specific functions.
>2. Living macroscopic "things" exhibit complexity at the same scale at
>which the "thing" is defined, hence they retain both definition and
>complexity.
>3. Non-living macroscopic "things" exhibit complexity only at a scale where
>the "thing" is no longer defined (or changes definition). Hence, in these
>cases, the "thing" does not retain both definition and complexity, and
>hence "it" is not complex (even though something else at this level is
>complex).
I had no intention to associate Rosen's
"complexity" with life or organization. Life requires a semantic
closure (self-observation), but in our discussion with Don we always
talked about human models of other things (which is a much simpler
matter).
>>2. Models of real systems may be mechanistic (attempt to
>>describe and control every detail) and non-mechanistic (that
>>have some internal freedom, e.g., neural networks,
>>genetic algorithms).
>I would suggest classing these as mechanistic and quasi-mechanistic (i.e.,
>incorporating concepts of freedom, such as uncertainty, into otherwise
>mechanical models). I do not understand how a model can be entirely
>non-mechanical without loosing the ability to define terms or reference
>something relevant to us. Even theological models employ ideas of cause and
>effect, which is part of the mechanical program. Do we not have difficulty
>discussing a non-mechanical reality without using mechanically-based concepts?
This is an interesting question! I believe that some models may exhibit
complex behavior in the following sense. Theoretically it is possible to
follow their dynamics using cause-effect chains. However, it will not help
us to understand how the model works because in the next run all
cause-effect chains may change. It will take millions of years to trace
all possible model trajectories and we still gain nothing. Theleological
or phenomenological explanations may appear much simpler and useful.
You can call this quasi-mechanistic models, but for me it looks like
true complexity.
>Can someone provide a specific example of an entirely "non-mechanistic"
>model that is neither metaphore nor metaphysics?
All models are metaphors (at least there is no way to prove that
they are not).
>how about (e) consider ALL models (including mathematics and logic) to be
>approximations of reality, mechanical models being best suited for those
>things that behave mechanically and quasi-mechanical models being best
>suited for those things that do not; and recognizing that in any ultimate
>ontology, all distinctions blur and only the instance of experience itself
>is left as a means of understanding.
"Approximation" makes sence only if you have a converging series.
Scientific revolutions do not show much of conversion. I prefer
to talk about metaphors. This is more safe because it does not
require convergence.
I would say that mechanistic models are good for modeling objects
with which we have simple interactions. It is amazing that very
complex processes like movement of cars on a highway in rush hour,
which involves a lot of passion, can be modelled by a couple of
simple mechanistic equations.
-Alexei
-------------------------------------------------
Alexei Sharov Research Scientist
Dept. of Entomology, Virginia Tech, Blacksburg, VA 24061
Tel. (540) 231-7316; FAX (540) 231-9131; e-mail sharov@vt.edu
Home page: http://www.gypsymoth.ento.vt.edu/~sharov/alexei.html