Message-Id: <34391B28.4B92@rug.ac.be>
Date: Mon, 06 Oct 1997 10:08:56 -0700
From: Mario Vaneechoutte <Mario.Vaneechoutte@rug.ac.be>
To: memetics@mmu.ac.uk
Subject: Re: Replicators, was Non Homuncular Memetics
Aaron wrote:
Mario wrote:
> >Indeed biologists have focused on nucleic acids, for many good reasons.
> >However, it is often forgotten that to replicate, a cell need not only
> >inherit these informational molecules, but also some minimum of
> >processors (enzymes) which can interprete and duplicate the DNA, and
> >also membranes: DNA does not encode the formation of membranes de novo,
> >it only encodes for enzymes which can synthetise new membrane taking
> >existing membrane (in some distant way resembling the way DNA is
> >replicated). The only independent replicator on Earth is the cell which
> >can be regarded as a system of molecules forming a closed semantic
> >circle. It is here that the basic dissimilarity with memes can be found:
> >memes are merely used for information exchange between different
> >processors. In opposition to genetic biology, these processors (I mean
> >us) are not encoded by the information contained in memes.
>
Aaron:
> As remarkable as "the cell" is, it is still an abstraction. As I pointed
> out months earlier, it "replicates" only with respect to an abstraction.
> You do not see "daughter cells" with the same number or placement of
> organelles, enzymes, water molecules, etc. Much abstraction is involved in
> deciding whether or not two cells are "the same" or "of the same kind." New
> humans, in contrast, at least bear a number and placement of organs that
> mostly resembles their parents (one parent more than the other, of course!).
Of course I agree, but I assumed this to be obvious: no matter can
replicate.
It is information that can be replicated. Or at least: more material
instantiations of the same information can be made. A duplicate of the
material gene is neither the same material gene (it is composed of other
atoms). But, it is a duplicate which contains the same information as
the model.
Aaron:
> I don't recognize the phrase "closed semantic circle," but "the cell" is
> certainly not a closed system. It is a material process, and as such is an
> essentially open system: it MUST have matter and energy flowing in and out
> in order to be "alive."
Of course again, this is not what I meant. Biological life can only be
understood by considering it as a giant process of interconnected
chemical reactions. You can't understand it by trying to figure out what
a living organism is on its own, in disconnection with the ecosystem it
lives in. With regard to matter and energy, a cell is an open system, I
certainly agree.
With regard to information, to 'meaning' it is the only closed system:
it contains information molecules which code for processors which can
make more of the information molecules. This is what I would call a
'closed semantic circle'. It is in this sense that I would consider the
cell as the only kind of independent information replicator.
As a matter of fact, at the level of the individual cell, it is
difficult to distinguish between phenotype and genotype: what is the
answer when I claim that the newly formed DNA-strands are in essence
nothing but a phenotypic product?
> It does not do anything by itself, let alone
> "replicate." To continue your project of forcing passive voice onto cases
> of "replication," we see that cells do not "replicate," but "are
> replicated" by sunlight, geothermal energy, geochemicals, water, etc.
Well, I tend to disagree. See above. There is really a tremendous
difference between what a cell (genes + enzymes + membranes + ...) does
and what happens when memes are replicated. Also, in case biological
information replication just needed a little sun etc., we shouldn't have
that much problems in explaining the origin of the cell (i.e. of life)
and we should see more spontaneous life.
> To flatly state that memes are merely used for information exchange ignores
> the wide range of causal roles that a meme can play in generating new
> copies of "the same" meme in different people. It is as if I had declared
> that "plasmids are merely used for information exchange between
> processors," ignoring, for instance, the fact that a plasmid can code for a
> protein tube that propagates plasmids (including "the same" plasmid itself)
> between cells.
PLASMIDS. You touch my favourits. I compare them to scientific writings,
which are also materialized (i.e. printed) pieces of information which
can be recombined in other scientists (bacteria). They are also a nice
example of horizontal spread of genes, while many assume that such
things are only rare (and that genetics is mainly about vertical
transmission and thus that - erroneously, I'd say - this is a major
difference with memetics).
One might object that bacteria do not communicate with each other like
scientists do. But do scientists communicate directly with each other
when they publish? As a matter of fact, they just send out (at random)
their newly acquired information under the form of a written paper into
the community of scientists. Some of these scientists will pick up some
ideas of the paper and recombine these with ideas from other papers. To
me, or rather from the information 'point of view', this looks pretty
much the same way as information handling by bacteria plasmids.
(I have to think about your interesting remarks on plasmids (memes)
propagating plasmids (memes): one must consider such statements
carefully, taking the point of view of the different 'interactors'.)
> As for whether you say that humans are "encoded" by "the information
> contained in memes," this strikes me as a matter of semantic taste, not
> particularly crucial to the theory.
I said that they were NOT encoded.
> I say that science is not BASED on building analog models, even though I
> admit that analogies often facilitate new insights. What is the analog
> model upon which biological evolution now DEPENDS? The inheritance of
> wealth--whence the word "heredity"? I doubt very much that many
> evolutionary scientists think about the inheritance of wealth in order to
> analyze the evolution of enzymes, for instance.
My excuses, but I do not understand what you mean with 'the inheritance
of wealth'.
Mario
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