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Well, that's all right, John M. I made an honest try. I don't know
if Carlos is still in the dark as well, but I don't see what could be said any
more simply or any clearer.
However, I will say that it would be to your benefit (and everyone
else who's trying to understand the work) to read the entire chapter on this,
and work at it-- because it's bedrock stuff. And if his description
of the relation between a model and a natural system doesn't make sense to
you, then you will really be lost trying to follow his discussion about the
relation between a model and a new model-- of the model!
I see another typo in Life, Itself, though: did anyone else catch
it? On the left hand side of the diagram, they scrambled the letters. They've
got "casual"! Sheesh. Columbia University Press.
Judith
PS: John, if you can come up with a way of illustrating the ideas
that would help clarify things for you (be it more examples or whatever),
let me know. OK?
----- Original Message -----
Sent: Monday, August 22, 2005 4:32
PM
Subject: Re: [ROSEN] Modeling relations
and semantics
Judith,
thanks for the diagram - I think it came through OK,
I
saw this dozens of times and never made any sense of
it. Now that you
were kind enough to paste the legend
underneath, I jumped excitedly on the
text and read it
2-3 times, forcing myself to read it
with
concentration. Itr still did not make any sense to me.
The
words (I almost learned them ny heart) seem of no
relevance with the
diagram, I still don't know what
the lines represent and what the
difference is between
an identically drawn model and a natural system
(I
know - at least I think I know) what it ought to mean,
but not from
the diagram or its legend.
I was so glad that after all those years I will
get an
understanding of - what Tim once wrote: "a diagram is
more
meaningful than 1000 words" - alas I got only to
the 999th word.
Is
there anybody - without perfect prior knowledge -
to understand the diagram
upon its legend?
Even your added explanatory text - which seems
so
clear does not (really) enlighte...
John M
--- Judith
Rosen <***>
wrote:
SNIP
> The 'legend':
>
> 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.
>
> 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
>
>
>
>
>
>
>
>
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