Re: Theories, models, and simplifications.

From: Perplexed in Peoria (jimmenegay_at_sbcglobal.net)
Date: 01/28/05 

Date: Thu, 27 Jan 2005 22:05:59 -0500 (EST)

"John Edser" <edser@tpg.com.au> wrote in message news:ctb5kf$p3l$1@darwin.ediacara.org...
>
>
> "Perplexed in Peoria" <jimmenegay@sbcglobal.net> wrote:-
> > > > > JE:-
> > > > > Hamilton's model is an OVER simplification
> > > > > of SOMETHING because it does not refer any
> > > > > of its variables to just one single constant term.
> > > > > Such oversimplified models normally replace
> > > > > one constant with another so they
> > > > > now constitute a contesting theory. Hamilton
> > > > > never replaced one constant with another
> > > > > he just deleted it. His model remains
> > > > > entirely irrational because of this
> > > > > fact. A headless model remains mathematically
> > > > > valid but rationally meaningless because
> > > > > the variables, which are all that is
> > > > > now left, can vary without limit.
>
> > > > JM:-
> > > > Could you explain to me what you think the constant is
> > > > in Darwin's theory, and could you point me to the section
> > > > of "Origin" in which he discusses it?
>
> > > JE:-
> > > Darwin implies one that is all.
> > > It can de exactly defined: the total
> > > number of fertile forms reproduced
> > > into one population by each parent
> > > HOW MANY MORE TIMES MUST I REPEAT
> > > IT
>
> > JM:-
> > John, rather than endlessly repeating yourself, may I
> > suggest that you try EXPLAINING yourself occasionally.
> > For example, you were asked to produce THE CONSTANT
> > in Darwin's theory, and instead you produce something
> > that everyone except yourself would call a collection
> > of variables. I'm sure you realize that this is
> > very confusing to people. Explain please!
>
> JE:-
> [snip charges of malice]
> Once the total number of fertile forms reproduced
> into one population by one parent has been completed
> it remains set in history forever unchanged, as that
> parents ONE fitness. [snip more charges of malice]

John, I think that I have just experienced what a
psychotherapist would call a "breakthrough". Let me
put my new understanding of your thinking into my own
words as a doublecheck that I have finally "got it".

Newton's theory of gravitation contains just one constant
G. The value of G is a contingent (to use one of Gould's
favorite words) fact of nature which has to be measured.
But the value of G is fixed for all time. G is not a
variable.

Newton's rule f=ma contains the symbol m. This "m" is
constant in a different way than G is, but it is still
a constant. We need to measure m once for each situation
that we study using f=ma. But in any particular situation,
we only need to measure it once - it remains constant
through time as the situation continues to be studied.
(There may seem to be exceptions to this (in rockets for
example), but these supposed exceptions involve
progressively ignoring part of the mass (the rocket exhaust).
Proper understanding of how to use f=ma would consider
that exhaust mass to still be part of the system being
modeled. (Mr. Kurtz, are you reading this? He is not
as confused as you think!)

Furthermore, both G in gravitation and m in mechanics
have similar epistemological roles:
1. They must be measured.
2. They remain constant through time.
3. Any attempt to remove them from consideration in a
model of the theory is inevitably going to result in
a model that is pathologically inferior to the
parent theory. Non-refutability is one possible
such pathology. John and I may remain in dispute as
to whether it is an inevitable pathology, but it is
certainly a possible pathology. And we agree that
some kind of pathology, some loss of something, IS
inevitable.

Now, what serves this epistemological role in Darwin's
theory? Well, where as we have a single measured
constant G in gravitation, and a multitude of measured
constants m in mechanics, in Darwin's theory we have
a huge multitude of measured constants. The fitness
of each and every organism that has ever lived is
such a constant. One such constant is Jim Menegay's
fitness - at least it will be a constant once I have
passed away and all of my sperm samples have been removed
from the sperm banks and all of my cells have deteriorated
to the point where cloning is no longer feasible.
(And all of my offspring have reached maturity.) This
fitness is a constant which has to be measured. It
is a value that will remain constant in time (once it
has been established). And finally, any model of human
evolution which deletes this constant will be forever
non-refutable.

Do I have this basically right, John? I definitely
now see this as a coherent viewpoint. I reserve
judgement yet on whether it is a useful viewpoint,
but I do see that there is some epistemological
commonality among these "constants".

I haven't yet completely worked out what Fisher's
and Hamilton's models do with these constant fitnesses.
My first impression is that they are not exactly
deleted - they are merely aggregated and averaged -
"smeared out" in some sense. Thus, my initial expectation
is that the worst pathology we should expect from these
models is a certain loss of accuracy. But, I have to
admit that I have not yet thought things through fully
from this new viewpoint. I remain open to further
enlightenment and further breakthroughs.

[snip]
> > > JE:-
> > > This maximand fitness can be
> > > tested to refutation. NO OTHER
> > > FITNESS MEASURE CAN BE. What
> > > does that tell you?
>
> > JE:-
> > Another very interesting claim. I wish you would explain
> > this one too. For example, you are suggesting that if the
> > word "fertile" had been left out of your definition, then
> > we would no longer have a refutable definition (whatever
> > THAT is). Why not?
>
>
> JE:-
> I claim that when "fertile" is left out
> ANY proposition of fitness stands refuted.
>
> A maximand fitness is a maximum (total)
> fitness count. If fitness counts
> never end then no fitness can be
> independent of any other so all
> relative comparisons of fitness
> counts remain arbitrary.
>
> Note:
> A definition could be refuted if and only
> if that definition is a part of a refutable
> theory. Everything is theory context sensitive.
> Therefore when I state a definition is refuted
> I do not only mean that definition, I mean
> the entire theory that employed it.

Well, I think that you are wrong that the theory with
the word "fertile" left out is any less refutable
than yours. Just take your basic experiment, and
force the number of offspring to remain constant
regardless of whether they are fertile or not. To
be honest, I don't see this as *more* impossible than
doing it in your theory - it is impossible in
either case.

Or come up with a different experiment. Surely, any
rational theory of evolution will have some individuals
whose fitness is measured to be zero. The only "advantage"
that I can see to your definition is that such individuals
are rare in your theory, but very common in mine. Well,
another advantage is that the number of individuals whose
fitness needs to be measured and recorded is smaller in your
theory. But that is surely only a practical advantage rather
than a fundamental epistemological one.

> ___________________________________
> You agree that Hamilton's Rule
> is 100% relative. Either define
> what it is 100% relative to,
> or throw out Popper. You
> cannot have it both ways.
> ___________________________________

When did I agree that it is 100% relative? Those sound
like your words, rather than mine. And, in any case,
I can't imagine that I would say that something is
relative without simultaneously saying what it is
relative to. Saying something is relative without
that stipulation is just meaningless. (Or, as you
might have put it, "just, meaningless".)

I have said that the rule can use either relative or
absolute fitnesses in the calculation of b and c.
And a "relative fitness" is, by definition, relative
to some "nominal" fitness - either the fitness of a
"wild type" or the average absolute fitness of the
population.

I have also said that the answer that the rule
provides is a relative answer - it tells us whether
the gene increases in frequency within the population.
It doesn't tell us whether the gene increases in
population.

Other than those two things, I don't remember using
the words "relative" and "Hamilton" in the same
sentence. So, please remind me of what it is you
think I said.

Relevant Pages

  • Re: Theories, models, and simplifications
    ... and I would disagree as to whether it is the ... > best notion of fitness. ... John just doesn't want to grow up. ... > thing about John's idea is his insistence that his way ...
    (sci.bio.evolution)
  • Re: Reviews of Unto Others
    ... John, I have never even seen the rule "rb>K" written down before. ... guessing that the new K is the fitness of an altruistic actor and ... What does it mean to "prove" altruism? ...
    (sci.bio.evolution)
  • Re: Theories, models, and simplifications
    ... > John Edser wrote: ... > Fitness" has no meaning to anybody but yourself. ... And, even that insistence is not so weird, if you accept ... Hamilton wrote his second paragraph. ...
    (sci.bio.evolution)
  • Re: Theories, models, and simplifications
    ... and I would disagree as to whether it is the ... >> best notion of fitness. ... None of them can halt natural selection ... John Edser ...
    (sci.bio.evolution)
  • I agree.
    ... until my skills and fitness improve. ... John ... > Superiority comes with the shooter. ...
    (rec.sport.paintball)