On Sun, 04 Jan 1998 03:04:07 -0800, Russell T. Cannon wrote:
RC>In a previous post, I gave a definition of the Darwinian evolutionary theory as I
>understand it to be:
[...]
RC>Stephen Jones replied:
>SJ>I can't see a clear distinction between the Special and
>>General Theory of Evolution. What is the difference between:
>>"1. Changes occur to the genomes of species."
>>and
>>"1. Natural mechanisms account for all changes to the
>>genomes of all species."
>>
>>Or between:
>>"2. These changes are caused and preserved by natural
>>mechanisms."
>>and
>>"2. All biodiversity on earth is attributable to these natural
>>mechanisms."
RC>The difference is the word "all". The Special Theory says that
>certain things happened. The General Theory does exactly what its
>name implies; it generalizes "some" observations onto "all"
>potential circumstances through "all" time. Saying natural events
>occur--the Special Theory--is not the same as saying they account
>for "all" possible events that could have occurred--the General
>Theory.
OK. It was not apparent to me that "1. Changes occur to the genomes
of species" and "2. These changes are caused and preserved by
natural mechanisms", is limited to only *some* genomes. Perhaps you
could insert "some" or "particular" between "of species" in 1.?
RC>Steve quoted from Denton:
>SJ>"In his book Darwin is actually presenting two related but
>>quite distinct theories. The first, which has sometimes been
>>called the "special theory", is...restricted in scope and merely
>>proposes that new races and species arise in nature by the agency
>>of natural selection...The second theory, which is often called
>>the "general theory"...makes the claim that the "special theory"
>>applies universally and hence that the...manifold diversity of
>>life on Earth can be explained by a simple extrapolation of the
>>processes which bring about relatively trivial changes...This
>>"general theory" is what most people think of when they refer to
>>evolution...' (Denton M., "Evolution: A Theory in Crisis", 1985,
>>p44)
RC>Notice the terms "applies universally" and "all...diversity" . I
>basically said--or at least meant to say--the same thing.
OK. But see below. There may actually be *two* definitions of the
General Theory of Evolution!
RC>He throws in the point at the end that is worth emphasizing,
>however, that when the average person thinks of evolution, it is
>the General Theory that he has in mind.
Yes. But it has ocurred to me that there is another definition of
the General Theory that is probably also what "the average person
thinks of evolution", namely universal monophyletic common ancestry:
"On the other hand there is the theory that all the living forms in
the world have arisen from a single source which itself came from an
inorganic form. This theory can be called the "General Theory of
Evolution" [macroevolution] and the evidence that supports it is not
sufficiently strong to allow us to consider it as anything more than
a working hypothesis..." (Kerkut G., "Implications of Evolution",
1960, p157)
These two definitions are not necessarily the same. If the tree of
life is monophyletic, then Denton's General Theory definition may
ultimately be the same as Kerkut's. But if it is a forest (ie.
polyphyletic) which is what Kerkut believed, then they are not the
same. I think the difference is that there really are two different
definitions of "evolution", one which is to do with the historical
pattern of evolutionary relationships (Kerkut's) and the other to do
with the evolutionary mechanisms which may have produced that pattern
(Denton's). Patterson makes this distinction between the historical
and mechanical aspect of evolution, clearer:
"If we accept Popper's distinctions between science and non-science,
we must ask first whether the theory of evolution by natural
selection is scientific or pseudo-scientific (metaphysical). That
question covers two quite separate aspects of evolutionary theory.
The first is the general thesis that evolution has occurred - all
animal and plant species are related by common ancestry-and the
second is the idea that the cause of evolution is natural selection
(in fact, Darwin arrived at the first idea about three years before
the second).Taking the first part of the theory, that evolution has
occurred, it says that the history of life is a single process of
species-splitting and progression. This process must be unique and
unrepeatable, like the history of England. This part of the theory
is therefore a historical theory, about unique events, and unique
events are, by definition, not part of science, for they are
unrepeatable and so not subject to test. Historians cannot predict
the future (or are deluded when they try to), and they cannot explain
the past, but only interpret it....there are no laws of evolution
comparable to the laws of physics, just as there are no laws of
history." (Patterson C., "Evolution", 1981, pp145-146)
RC>The difference between the Special and General Theories of
>Evolution are wholly beyond the knowledge or interest of the
>average person. It is enough for him to "know" that scientists
>have proved evolution to be true because they've discovered the
>minor changes occurring in nature. Little does he realize that the
>generalization of these changes into the entire biosphere is no
>more proven now than in Darwin's day. The part remains a theory is
>the very part that most people believe is solidly proved.
Agreed. And apart from the rare exceptions like Kerkut and
Patterson, these crucial distinction between General and Special
theories and between history and mechanisms, are not made. This
thriving on definitional confusion is evidence that evolution is
largely pseudoscience. Real science would do its utmost to clarify
its crucial terms for the general public (let alone its
practitioners), not keep them confused!
God bless.
Steve
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Stephen E (Steve) Jones ,--_|\ sejones@ibm.net
3 Hawker Avenue / Oz \ Steve.Jones@health.wa.gov.au
Warwick 6024 ->*_,--\_/ Phone +61 8 9448 7439
Perth, West Australia v "Test everything." (1Thess 5:21)
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God bless.
Steve
--------------------------------------------------------------------
Stephen E (Steve) Jones ,--_|\ sejones@ibm.net
3 Hawker Avenue / Oz \ Steve.Jones@health.wa.gov.au
Warwick 6024 ->*_,--\_/ Phone +61 8 9448 7439
Perth, West Australia v "Test everything." (1Thess 5:21)
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