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[Phys-L] Re: Another attack on Evolution



For want of a better word I used analytic instead of, for example,
testable. However, I'll continue.

http://en.wikipedia.org/wiki/Analytic_truth

note the "converse" synthetic:


http://en.wikipedia.org/wiki/Epistemology#Synthetic_and_analytic_statements


and a comment on the distinction:


http://en.wikipedia.org/wiki/Willard_Van_Orman_Quine#Rejection_of_the_analytic-synthetic_distinction


Returning:


inserting the word "enuf" makes most statements (all?) untestable. One
may simply assert when, your example, no new specie has evolved, "you
didn't wait long enuf". This may be continued "ad infinitum".

This example may be syntheticised (a bcn) by invoking paleontological
data and more recently dna mutation rates, etc.

bc, very amateur philosopher.

p.s. "sufficient number of generations" is equivalent to long enuf.


Hugh Haskell wrote:

At 23:12 -0800 1/21/06, Bernard Cleyet wrote:


This [long enuf] is an analytic statement, therefore, that argument
is invalid.



Sorry Bernard, I don't understand this statement. Perhaps I am
unlettered in the rules of formal logic, but I fail to see why the
argument cannot be valid. What I am saying is that if we look at the
offspring over a sufficient number of generations, we may find the
offspring sufficiently different from the ancestor that we are
justified in asserting that it is a new species (note that it is not
required that a new species emerge, ever, but it is possible, given a
sufficient number of generations). What I mean by a "sufficient
number of generations" is enough that the observed changes between
the ancestor and the latest offspring are significant. there is no
way to predict this number in advance. It may be a relatively short
number, or it may never happen. I do know about the mitochondrial DNA
bit, but I don't see how that affects my argument, except perhaps
putting it on a more firm footing. However, one cannot define a
species boundary by mitochondrial DNA, either, so we cannot date the
emergence of a new species form that evidence alone, but we can use
it to date the era when an earlier species whose fossilized remnants
are found existed. Although, I guess that we could use that
information to work backward from the DNA of two related existent
species and figure out when their lineage merges (looking backward in
time), and thus put an upper limit on the age of a species.



I was told different species can't produce fertile offspring. I
suspect in the course of change a time comes when there are two
lineages that, tho mating would be successful, don't mate because
they "look ugly" to each other (metaphor). At this point change will
accelerate to the point they are "really" different species.



I don't think this is either a necessary or sufficient condition for
defining a species. It certainly is rather difficult to verify if we
are talking about species definition from the fossil record, since we
have no examples that we can point to and claim that they can or
cannot produce fertile offspring.
I believe that I have read about organism that have been asserted to
be different species (a difficult task among closely related
specimens) even though they did produce fertile offspring.

I remember a novel from, I think, sometime in the 50s or maybe a bit
earlier, called "The Missing Link," in which a variety of humanoid
simians is discovered on Borneo, or somewhere like that, that seems
to be so closely related to humans that it was questioned if this was
the missing link between apes and humans. To attempt to settle the
issue, one of the scientists impregnates a female, who gives birth
and then the scientists kill the infant. They are tried for murder
and the argument they make in their defense was that the infant was
not a human, and so it could not be murdered. I don't remember how it
turns out. It's an interesting premise, but I doubt if it has any
scientific validity.

Hugh
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Hugh Haskell
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<mailto:hhaskell@mindspring.com>

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