Date: Sun, 12 Apr 1998 16:19:58 +1000
From: John Wilkins <wilkins@wehi.EDU.AU>
Subject: Re: Memes are Interactors
To: memetics@mmu.ac.uk
| From: Aaron Lynch <aaron@mcs.net>
| Date: Sat, 11 Apr 1998 15:58:36 -0500
| Subject: Re: Memes are Interactors
| >Well, I wouldn't want to be thought a charlatan, even if I am a
| >pseudoscientist. There are far too many in memetics already. I meant,
of
| >course, to say that physical systems (both storage and transcription)
| >are subject to thermal agitation (a term I take from Leon Brillouin's
| >_Science and Information Theory_, Academic Press 1956) and therefore
the
| >reading of information from a storage substrate will result in
errors.
|
| This is a different point from the one you asserted before, so thank
you
| for clarifying. It is best to specify the storage substrate and the
| information you intend to read. A vacuum tube flip flop, for instance,
will
| show more errors if it has too little thermal agitation, and more
errors if
| it has too much. The same for typical transistor flip flops, neurons,
etc.
| A diskette, however, should retain its data better at nearly 0 Kelvin,
| unless of course materials with mismatched thermal expansion
coefficients
| destroy it during chilling. So I agree that the reading of information
from
| a storage substrate will involve a non-zero error rate, but the rate
of
| error depends upon what information you want to read and how it is
stored.
So, you agree with me that (as I first said, correcting for a typo) "the
physical systems in which information is stored degrade as a function of
thermodynamic entropy", that is, the systems degrade due to a
thermodynamic effect. This is not a different point but a restating of
the same point. Note that I do not specify what sort of entropic change.
|
| >Since each instance of a meme is some form of physical information
| >storage system, this means that the replication of a meme will, on
| >occasions and no matter what the error correction process, inevitably
be
| >subject to change. If this isn't endogenous change, then I would
| >appreciate your better informed definition of what would be. By the
way,
| >the book by Brillouin is found in my university library, if that's of
| >any moment, and I understand Brillouin himself was a physicist of
some
| >note.
|
| >The reason I stated it the way I did was to make it clear that
| >informational entropy isn't thermodynamic entropy. Thermodynamic
| >fluctuations introduce noise into any information propagation channel
| >and hence memes are inevitably and measurably going to change since
| >copies will vary from the urmeme. Any selection coefficient equal to
| >several or many times that rate will define memes, according to my
| >definition.
| >
| >I explicitly *do not* think that we could predict the direction (or
| >exact time) of a memetic mutation. I am sorry if I gave that opinion
in
| >anything I wrote (did I?). However, as memes can be stored in and
| >transcribed from all manner of physical systems other than just
brains,
| >I do not understand why one must leave it at that at all.
|
| You are clearly one who prefers a rewriting the definition of "meme"
in a
| way directly contradictory to Dawkins and others. To my thinking, the
way
| you have done this is akin to rewriting the definition of "gene" to
refer
| to information stored and transcribed in all sorts of physical systems
| other than nucleic acid, (or, more generally, whatever an organism's
| "genetic material" may be.) This being the case, it is worth noting
that a
| great enough reduction in the thermodynamic entropy of your computer
will
| also wipe out all of the information that makes the device useful to
you.
Is this a rewriting of Dawkins? In his "Replicators and Vehicles" (1982)
he states, in response to Gould's criticism of the selfish gene
metaphor, that
A replicator may be defined as any entity of which copies are made. ...
A
germ-line replicator, ... is the potential ancestor of an indefinitely
long
line of descendant replicators. Thus DNA in a zygote is a germ-line
replicator... There is a problem over how large or how small a fragment
of
genome we choose to regard as a replicator. ... The answer I have given
before, and still stick by, is that we do not need to give a straight
answer
to the question. Nobody is going to be hanged as a result of our
decision.
Williams recognized this when he defined a gene as "that which
segregates and
recombines with appreciable frequency (p. 24), and as "any hereditary
information for which there is a favorable or unfavorable selection
bias
equal to many or several times its rate of endogenous change" (p. 25).
It is
clear that we are never going to sell this kind of definition to a
generation
brought up on the "one gene-one protein" doctrine, which is one reason
why I
... have advocated using the word "replicator" itself, instead of
"gene" in
the sense of the Williams definition. Another reason is that
"replicator" is
general enough to accommodate the theoretical possibility, which one
day may
become observed reality, of nongenetic natural selection. For example,
it is
at least worth discussing the possibility of evolution by differential
survival of cultural replicators or "memes" (Dawkins, 1976; Bonner,
1980),
brain structures whose "phenotypic" manifestation as behavior or
artifact is
the basis of their selection. [1984 version: 163, 164]
Now here we have all the elements of my own definition implicitly or
explicitly stated back in 1982. Dawkins says that replicator size is
arbitrary, replicators are information not nucleotides, the Williams
definition is the basis for memes, behaviour/artifact (note: not just
brain structures store memes, a point made by Brillouin 25 years
earlier) is the phenotype.
Apart from my insistence in a forthcoming Biology and Philosophy paper
that some memes at any rate are particulately inherited, Dawkins and I
are saying exactly the same thing. That is not revisionism but
explication.
<snip>
|
| I am not going to argue with the statement that endogenous change is a
| property of physical storage systems. But I am glad that the attempt
to
| describe this simply as a function of thermodynamic entropy was
| uncharacteristic.
I cannot see that you have actually shown my initial statement was
wrong, but leave that aside for now - we could argue that ad infinitum.
At least you accept that endogenous change is how I characterise it.
|
| The main pseudoscientists and charlatans I allude to, of course, are
the
| ones who attempt to invoke the second law of thermodynamics as an
argument
| against biological evolution. Naturally, I would rather not see
erroneous
| "second law" arguments emerging in memetics.
I entirely agree with this. I'm a talk.origins denizen, and can testify
to the ubiquity of thermodynamic mumbo-jumbo by anti-evolutionists.
However, that's entirely different from stating the truism that
thermodynamics introduces noise. I never made any claim about novelty
being the result of either an increase or decrease in entropy. Novelty
is the result of changes in entropy relative to the prior state.
|
| >Elsewhere in this thread you wrote
|
| [posted under the thread "Re: List of meme definitions"]
Sorry, my mistake. I get this in digest form.
|
| reinserted:
| >>"meme
| >>The least unit of sociocultural information relative to a selection
process
| >>that has favourable or unfavourable selection bias that exceeds its
| >>endogenous tendency to change." Wilkins ("What's in a Meme")
| >
|
| >| In addition to the points Paul raises, this definition [my defn -
JSW]
| >| runs into another
| >| problem: It requires development of a full ordering system (set
| >theory)
| >| whereby given any two units of sociocultural information, you can
| >| unambiguously decide that one is larger, smaller, or the same size
as
| >the
| >| other. Only then are you entitled to use the term "least" in the
| >| definition. See section 12 of my new paper.
| >
| >One is surely entitled at least to measure the length of a message in
| >bits. The least bit length message that is subjected to selection is,
at
| >that level of complexity, a meme, and can be compared to alleles in
the
| >meme-pool of some cultural population. What I find hard to conceive
how
| >one could resolve on most other definitions is how to even identify a
| >competitor meme. My definition is supposed to flag (though it doesn't
| >identify or clearly spell out) that issue.
|
| Section 12 of my paper does mention that full ordering systems are
easily
| constructed for texts and nucleic acids. But in [order] to ever
consider
| brain-stored information (memory items) as memes, you would need a
full
| ordering system for them before incorporating a "least units" phrase
in the
| definition.
Why "for them", that is, for brain states? How information is stored is
not relevant - how information is expressed and transmitted is. That's
what makes a replicator. There is a category error in identifying brain
states with concepts that is well known in the philosophy of mind. Apart
from anything else, how a brain state is located in a context determines
its meaning.
Nor do you need to make information content absolute. It isn't absolute
in Shannon Weaver characterisations of DNA or proteins, either. You
first find the empirical distributions to calculate the informational
entropy (call it intropy to avoid confusion - Brooks and Wiley do this,
IIRC). All comparisons can be made according to the number of bits of
the DNA-RNA code. This code is more or less imposed on us by the natural
process, but it is neither absolute nor consistent. The difficulty with
culture is one of finding the appropriate protocol - a metalanguage to
express allele memes - but although the operational problem is greater,
it is not insurmountable, and has been more or less intuitively done in
history, sociology and anthropology for a very long time, Quinean
translation problems notwithstanding.
|
| As for finding competitors, contrary beliefs are often good examples
of
| memes that compete in a population. Beliefs that "abortion is murder"
and
| "abortion is a right," for instance, propagate as contrary
competitors.
It is circular to argue that we can identify alleles in order to find
alleles. That these things propagate in competition is something you can
only find out if you can first individuate them, and you cannot assume
that this is unproblematic, as your definition seems to do. This is
analogous to the same problem in systematics between phenetics and
cladistics. The choice of phenotypic traits ("phenes") was quite
subjective in phenetics if it wasn't based on theroretical
considerations, and that's what sank it in the end, although many of the
techniques survive.
|
| I do not see you offering any method to distinguish a "size"
difference
| between (for example) the the idea that people represent with the
phrase
| "abortion is murder" and the idea that people represent with the
phrase
| "abortion is mortal sin" even within a single brain, let alone between
| brains. Nothing you say below solves this problem either. You need to
| develop the ordering system not just for textual information, but also
for
| brain information before treating information unit sizes as knowable
within
| a definition of "meme." It would also help if you could choose a
| non-arbitrary ordering system, which for text would include such
| possibilities as letter counting or binary magnitudes of concatenated
ASCII
| byte values. Other reasons for not going with "size" restrictions
appear in
| my paper.
I must read it in detail. I read the draft you had on the web but
haven't had time to get to the full version. However, you appear to be
hung up on the word "size". I mean "least" in the sense of
"nonredundant", which was the point of the S and P example left in
below. Something is redundant if it is expressed in numerous different
ways. Nonarbitrary is nice, but in the end all metrics are arbitrary in
the sense that an infinite number of alternate metrics are possible,
parsimony considerations notwithstanding. What does matter is that
whatever more or less arbitrary metric we do use, the comparisons are
objective. [Arbitrary is not a synonym for subjective.]
What does behaviour X and behaviour Y have in common when they are
expressions of the same meme? In my paper I wrote:
If, as I have argued, a meme exists in virtue of biased transmission
rates,
then there is no smooth reduction of memetic structures from cultural
behaviour to atomic memes, just as there is no smooth reduction from
phenotypic traits to single genes. The researcher seeking to explain a
singular historical shift of memetic frequencies must iteratively
refine the
data until it becomes clear what is being transmitted at a level and
how it
is being expressed. The problem of classification lies at two ends of
the
scale - identifying cultural traditions as they exist now and over
time, and
identifying elements of those traditions as they persist and recombine.
Although this sounds subjective, it need not be. Behavioural
regularities
indicate that something objective has been spread, and even if the
underlying
memes cannot be formulated in some universal logical language, the
structure
of memes can still be identified in the same way as Mendelian genes and
molecular sequences, through the use of consensus maps and by noting
when
their absence or presence makes a difference.
This was rather aphoristic, but the inference is that we must begin in
the middle (in media res), as it were, and seek to identify parts and
wholes. We can do this, and indeed we do it every time we evaluate an
expression in a natural language. We find kinds, types, classes and so
forth. What they have in common is some structure, which when encoded in
transmission becomes information, and that *can* be measured in Shannon
Weaver bits.
|
| >A set theoretic approach requires a full understanding of
| >classification. One must be able to determine the set membership
| >criteria. But that is entirely distinct from determining whether one
| >message is commensurate with another. Moreover, there is a sense of
| >logical exclusion of statements in which if message A is exclusive of
P,
| >then S = (A or B or C) is exclusive of P. If we always transmit (A or
B
| >or C) as a unity then S is commensurate with P, even if P is just a
| >simple atomic proposition like A, B and C. Size doesn't matter as
such,
| >rumours to the contrary notwithstanding. What does matter is that S
and
| >P share a metric and are exclusive coordinates in that metric. The
| >*metric* is what selection defines, in terms of what is an allele in
| >that population.
Refs
Dawkins R: 1982. Replicators and Vehicles. In King's College
Sociobiology Group eds, _Current Problems in Sociobiology_, Cambridge
University Press. I'm citing the version in Brandon R and Burian R eds,
_Genes, Organisms, Populations: Controversies over the Units of
Selection_, Bradford/MIT Press, 1984.
Brooks DR and Wiley EO: 1988. _Evolution as Entropy: Toward a Unified
Theory of Biology_, second edition, University of Chicago Press.
John Wilkins from home
<mailto:wilkins@wehi.edu.au>
Not at all. I delight in all manifestations of the terpsichorean Muse.
===============================================================
This was distributed via the memetics list associated with the
Journal of Memetics - Evolutionary Models of Information Transmission
For information about the journal and the list (e.g. unsubscribing)
see: http://www.cpm.mmu.ac.uk/jom-emit