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Re: Why four categories of causation?
- From: Tim Gwinn <***>
- Date: Wed, 12 Jan 2005 21:42:14 -0500
Arno,
AG:
> For instance, in the famous
diagram of fig.
> 10.C.6 in LI there is an interesting double relation
between Phi,
> B and F:
>
> 1) B is material cause (Phi being
efficient cause and F outcome)
> 2) B is efficient cause (F material
cause, Phi outcome)
>
> So the 'really' interesting point, I think,
is: what does this
> relation between B and F look like, apart from the
definition of
> these various causal relations? There MUST be some kind
of
> ambiguous process going on, that can be interpreted as
material
> or efficient relation, but how do these two relations mix up
in
> their physical realization? It is in answering such questions,
I
> think, that Aristotle's causal system may not be sufficient
here.
The questions about the realization of this model has haunted me
for about as long as I have known of it. I still have difficulty fully
understanding the replication mapping Beta insofar as its meaning in physical
terms. I believe B as an efficient cause in ch. 10 of LI is related to Rosen's
comments waaay back in ch.6 on p. 157 about evaluation maps. There he talks
about how one could equally write s(f) for f(s). (I know it should be
an s with a circumflex over it, but this is the closest symbol I could find
in Outlook.) The example he uses for the physical interpretation of the
evaluation map is that of a meter: the meter value is caused by s
forcing the meter (which is designed to respond in a predetermined
manner) such that a certain meter value results, so s is more naturally
seen as the efficient cause rather than s being considered an "input" (i.e., a
material cause) to f.
In a similar way, if we have the repair mapping
F:B ® H(A,B)
then the evaluation map b Î B is
b:Fb ® H(A,B)
So, as I read this, a metabolic output b is
to be considered as a forcing upon the process F,
thereby causing a certain set of mappings H(A,B). The inverse of the
evaluation mapping is
b-1:H(A,B) ® Fb
But, since Fb
is the mapping B ® H(A,B), then the inverse of the
evaluation mapping can be rewritten as
b-1:H(A,B) ® H[B ® H(A,B)]
which is the desired replication mapping b.
I can understand how, using the meter analogy,
some 'input' b to F can be actually be the forcing
agent, causing F to produce a certain set of
mapping H(A,B). Of all that is unclear to me, the most unclear is the physical
interpretation of the inverse mapping. In that case, there is a set of mappings
H(A,B) which are forced (by b-1)
to produce a certain set of repair components. If H(A,B) is the set of
mappings which include the metabolic 'enzymes' (such as f), then
this seems to me to say that the set of 'enzymes' (or perhaps better, the
creation of 'enzymes'?) are being forced in such a way as to result in a
certain set of repair components.
It would probably help if I somewhat
understood "the embedding of a vector space into its second dual". Rosen refers
to the evaluation map as an abstract version of this [Found. of Math. Bio. 1972,
Vol. 2 p. 235 and BMB Vol. 21,p. 116, 1959].
Any ideas or thoughts?
Regards,
Tim