Carlos Limarino wrote:
As you surely understand, since Rosen said:
"I have been, and remain, entirely committed to the
idea that modeling is the essence of science and the
habitat of all epistemology."
And the fact he bases controversial claims about the
epistemological status of sciences like physics,
chemistry and molecular biology in his notion of
'modeling relation', I think is very important to
define clearly and rigorous the whole idea in order to
determine if is coherent from a logical point view.
"I have been, and remain, entirely committed to the
idea that modeling is the essence of science and the
habitat of all epistemology."
And the fact he bases controversial claims about the
epistemological status of sciences like physics,
chemistry and molecular biology in his notion of
'modeling relation', I think is very important to
define clearly and rigorous the whole idea in order to
determine if is coherent from a logical point view.
Of course I understand. In fact, I agree with you. I think, perhaps
it might be most useful to first lay out his (Robert Rosen's) concept
of what a model is/what it can be-- and also what is not a model, in his
view. After that, I can address the semantic issue and try a different way of
illustrating what I mean.
On page 60 of Life, Itself there is figure 3H.2,
which diagrams the modeling relation between a natural system and a formal
system (and is the one you were referring to in your original post). I will
attempt to cut and paste it into this email (if it doesn't work, use the book
for a reference).
N = the Natural system, F = the Formal system (or supposed
"model"). The arrow numbered (1) = the entailment within the natural system
(causal entailment). If we want to make a model that will be of any use
at all in dealing with this natural system, we need to recreate the
causal entailments of that system (sometimes called the "entailment
structure" or the "entailment pattern") in the formalism as inferential
entailment (represented here by (3). The processes for doing so are
diagrammed by arrows (2) and (4); encoding and decoding, respectively. If we can
recreate the entailment of the natural system with sufficient accuracy in
our formalism, when we test our formalism in the final phase... it
accurately predicts the behavior we actually observe in the natural system. (...
and there is much celebrating!) At this point, we can call our formalism a MODEL
of N. Another way to put that, using the number labels from this diagram, is:
"IF the information we get via the pathways 2 + 3 + 4 = the information we
get via pathway 1, THEN F is a model of N.
Note: There is a warning, issued on page 54 (it actually starts on
the bottom of page 53 and finishes at the top of 54) about the multiple
different uses of the word "model" by science and by many other fields outside
of science. He stipulates that within his own work, he won't use the word in
inconsistent ways, but he warns that one must understand his particular
definition or else nothing will make sense. So, if his definitions don't seem to
coincide with what you may have learned elsewhere, then set aside the earlier
definition while you are studying the ideas in Robert Rosen's work and use his
own particular definition.
I don't know if I understand it in the sense you want
it. If the idea is that the instrument used for
measure a physical quantity is not part of the system
being measured, that seems rather obvious to me, but
I'm afraid I don't see how to relate the metaphysical
idea of the existence of different objects to the idea
that a meter or some other instrument is a semantic
element to a given system, since when I replace m and
v in 'Et=1/2m*v^2' with the same numbers it gives me
the same result, independently how I measured mass or
velocity (and this is assuming Rosen reference to a
system is to what he calls the 'formal' one, if not,
I'm completely lost in what he means in his book).
So, where the 'semantic element' is being introduced
is a mystery for me.
Now we are ready to talk about the semantic elements, and there are actually quite a few. Looking at the diagram: the processes represented by the arrows are not actual material "things". Arrows (1) and (3) represent aspects internal to each of the systems (their internal entailment structures) and arrows (2) and (4) represent processes which are not a part of either system. So, in this diagram, encoding and decoding are "unentailed" from within either system. Instead, they are entailed by the modeling relation, itself, which WE have created. That's the "creative act of a free intellect" Einstein was referring to.
it. If the idea is that the instrument used for
measure a physical quantity is not part of the system
being measured, that seems rather obvious to me, but
I'm afraid I don't see how to relate the metaphysical
idea of the existence of different objects to the idea
that a meter or some other instrument is a semantic
element to a given system, since when I replace m and
v in 'Et=1/2m*v^2' with the same numbers it gives me
the same result, independently how I measured mass or
velocity (and this is assuming Rosen reference to a
system is to what he calls the 'formal' one, if not,
I'm completely lost in what he means in his book).
So, where the 'semantic element' is being introduced
is a mystery for me.
Now we are ready to talk about the semantic elements, and there are actually quite a few. Looking at the diagram: the processes represented by the arrows are not actual material "things". Arrows (1) and (3) represent aspects internal to each of the systems (their internal entailment structures) and arrows (2) and (4) represent processes which are not a part of either system. So, in this diagram, encoding and decoding are "unentailed" from within either system. Instead, they are entailed by the modeling relation, itself, which WE have created. That's the "creative act of a free intellect" Einstein was referring to.
The other sticking point seems to be the notion of a measurement
being a human semantic element. I think the main problem you are having is the
training, in science, to view all measurement as "objective information". What
RR is asserting is that this is incorrect. Not only is a measurement completely
outside the entailment structure of the natural system we derive it from, but it
is also irrelevant to that natural system. To measure the length of a
snake, for example, and come up with a number; this has no relevance for the
snake. It's about science, which is a human creation. We have seen that there is
a correlation between length and age in organisms like snakes, so we take a
measurement in order to compare it with other measurements. If the number is
high, our meter tells us that means it's a long snake and our correlation
tells us that if it's a long snake, it's likely to be an old snake. But each
species of snake has its own starting point, so the measurement and the meaning
of the correlation are all going to be context dependent. Some species of snake
may be longer at birth than other species when they are old. Do you see? These
are all relational values and they are not available from inside the measurement
system, from inside the model which correlates length with age.... and they
certainly aren't available from the snake's entailment structure.
Is this beginning to coalesce for you?
Judith
