Revised Tautology FAQ - Thread-2
Friar Broccoli
the original here:
http://groups.google.com/group/talk.origins/browse_frm/thread/ee571605fbebcd8b
consequently it will soon be impossible to find anything in that
thread.
______________________________________________________________
On Aug 16, 1:32 am, in
http://groups.google.com/group/talk.origins/msg/ca9b9c6f41842004
ivar wrote:
[snip]
> Perhaps, you could write a paragraph or two describing what you think
> should be in the FAQ tautology page relating to "SoF as a tautology."
> You can steal my words or Darwin's if that helps.
I made a stab at putting the tautology arguments into a couple
of paragraphs, but found I couldn't do that sensibly without
building a context, so I rebuilt the FAQ, steeling liberally
mostly from you but also from pretty much everybody who
has thus far contributed to the discussion.
I hope that folks here who actually know what they are talking
about, like Wilkin's, Ernest Major, and Harshman will find my
effort worth their time to criticize. The writing needs more
work too, but first the errors need to be squeezed out.
Here's my effort.
______________________________________________________________
Summary: The claim that evolutionary theory is unscientific or
unfalsifiable because it is a tautology rests on a
misrepresentation of, and focus on, the expression "Survival of
the Fittest" as well as a misunderstanding of the properties of
a tautology.
Darwin unwittingly created the tautology problem when, in the
fifth edition of his "On the Origin of Species," he changed the
title of the fourth chapter from "NATURAL SELECTION" to "NATURAL
SELECTION; OR THE SURVIVAL OF THE FITTEST." He wrote that he
did this because "Several writers have misapprehended or
objected to the term Natural Selection" on the basis that nature
can't "select" in the way that man can "select".
Unfortunately, some people now focus on the phrase "the survival
of the fittest" arguing that because it is a tautology, natural
selection and hence all of the theory of evolution is a fraud.
However, the words "survival of the fittest" do not by
themselves define evolution, which includes other processes such
as Mutation, Genetic Drift, and so on.. Rather, "survival of
the fittest" is more like an advertising slogan or label,
focusing attention on a key idea in the natural selection
process. Here, note that for Darwin "The Survival Of The
Fittest" was a synonym for, or subset of, "Natural Selection"
yet no one argues that "Natural Selection" is a tautology.
A simple version of the so-called 'tautology argument' is this:
- Through the process of natural selection, the 'fittest' survive.
- Who are 'fittest'? The ones who survive.
- Thus natural selection merely asserts that those who
survive survive, a tautology. It just says the same thing twice.
- As a tautology, it cannot be tested because it cannot be
false. Hence, natural selection and thus the theory of
evolution are not scientific. Thus, the proponents have leapt
from asserting that the phrase 'Survival of the Fittest' is a
tautology to the wider claim that 'evolution' as a whole is
not a scientific theory.
In order to understand the argument it is useful to ask, what is
meant by 'tautology'. Tautologies are True by definition and
may be characterised as follows:
- repetition of meaning, using different and dissimilar words or
symbols to effectively say the same thing twice.
- true by the meanings of words, true by the use of syntactical
elements
- not dependent on empirical testing (observations from the real
world)
Here are some examples of tautologies:
- false myth
- a bachelor is an unmarried man
- tomorrow is another day
- Green baby swans are cygnets the colour of grass
From the above it should be clear that a tautology refers
exclusively to formulas, in the above cases word or syntactic
formulas. The fact that a phrase is a tautology is not evidence
that the real world does or does not contain anything
corresponding to the content of the tautology. Since evolution
is a theory about the real world, it stands or falls on real
world verification, not linguistic distinctions.
So, is "Survival of the Fittest" a Tautology?
Well, in population genetics there is a formal variable called
fitness which is measured by the proportion of a trait that
survives into the next generation. The simplest form of the
equation looks like this:
W_abs_ = N_after_/N_before_
where:
W_abs_ is absolute fitness
N_before_ is the Number of individuals with some genotype
in a first generation (before selection)
N_after_ is the Number of individuals with an alternative genotype
in the following generation (after selection)
So quite clearly just as 'bachelor' is defined as 'an unmarried
man' 'fitness' is here defined as the 'survival' rate in the
following generation. Thus, it is clear that the expression
"Survival of the Fittest" is a tautology.
However, note that:
W_abs_ = N_after_/N_before_
is also a tautology since it is just another way of saying
"Survival of the Fittest". Indeed all axiomatic mathematical
expressions containing a single equal sign between two sets
of expressions are similarly tautologies. This includes
Newton's F=ma and Einstein's E=MC^2.
F=ma is of particular interest here because although it is a
tautology, it has in fact been falsified. That is, it is not
true in relativistic frameworks, a fact which has been
observationally verified. Similarly, "white swan" was once
thought to be a tautology, up until they found black ones in
Australia. Thus, being a tautology, does not immunize a
statement from being falsified by observation.
And indeed to some extent, like Newton's laws of motion,
"survival of the fittest" has itself been falsified by science.
When Darwin wrote, he knew of no criteria for survival other
than fitness (assuming that sexual selection is included as part
of fitness), but since his passing the study of genetics, which
he knew nothing about, has shown that genetic drift is a majour
determinant of inherited characteristics. Essentially, random
mutations which may code for characteristics having little or no
'fitness' value become fixed in populations essentially by
chance. So arguable the tautology under discussion here should
read "survival of the fittest and luckiest".
So even if it were the case that 'Survival of the Fittest' was a
complete description of the theory of evolution, asserting that
it is a tautology does not make it unfalsifiable.
Consider also that there is widespread agreement that, at least,
microevolution is falsifiable by testing. Phillip Johnson, no
friend of Darwinism, writes that "...everyone agrees that
microevolution occurs, including creationists" (Darwin on Trial,
page 68). People who try to breed faster horses or smaller dogs
(e.g., to create cute, tiny pets for city dwellers) or to breed
more productive strains of wheat or citrate-eating bacteria are
all, in effect, testing evolution using artificial selection.
If they consistently failed in these efforts, evolution would
thereby be falsified. (Examples of natural selection in nature
include the peppered moth and Nylon-eating bacteria. (For
evidence that macroevolution is testable, see 29 Evidences for
Macroevolution.))
Another deeper problem with the tautology argument is that
although 'fitness' (the label) is conceptually identical with
increased survival and replication, in the real world fitness
refers to a set of detailed characteristics that develop and are
maintained in response to specific environmental conditions.
Together these environments and the characteristics that evolve
in response to them form a causal account which is anything but
tautological. For example:
- Some non-poisonous butterflies develop bright coloration that
mimics the form of poisonous butterflies, because birds learn
from the poisonous variety to avoid that pattern.
- The peppered moth turned black and then returned to a peppery
coloration as its environment changed making one pattern and
then another harder for predators to detect.
- Sloths slowed down almost to a stop, because a slow moving
animal with blue-green algae growing in its hair is very
difficult for predators to see.
There is nothing tautological about:
- survival of the most colorful or
- survival of the slowest.
and should that be:
- survival of the pepperiest or
- survival of the blackest?
Without a causal account we cannot say.
Karl Popper [1976: sect. 37] also had doubts about whether
"Darwinism" was a testable scientific theory. According to
Popper, any situation where species exist is compatible with
Darwinian explanation, because if those species were not
adapted, they would not exist. That is, Popper says, we define
adaptation as that which is sufficient for existence in a given
environment. Therefore, since nothing is ruled out, the theory
has no explanatory power, for everything is ruled in.
This is not true, as a number of critics of Popper have observed
since (e.g., Stamos [1996] [note 1]). Darwinian theory rules out
quite a lot. It rules out the existence of inefficient organisms
when more efficient organisms are about. It rules out change
that is theoretically impossible (according to the laws of
genetics, ontogeny, and molecular biology) to achieve in gradual
and adaptive steps (see Dawkins [1996]). It rules out new
species being established without ancestral species.
All of these hypotheses are more or less testable, and conform
to the standards of science. The answer to this version of the
argument is the same as to the simplistic version - adaptation
is not just defined in terms of what survives. There needs to
be a causal account available to make sense of adaptation (which
is why mimicry in butterflies was such a focal debate in the
teens and twenties). Adaptation is a functional notion, not a
logical or semantic a priori definition, despite what Popper
thought.
Thus, the tautological attack on evolution fails because:
- "Survival of the Fittest" is not a complete description of
evolution. It misses, among other things, genetic drift.
- 'Fitness' in the context of a casual account is not
tautologically equivalent to survival.
- Tautologies are unfalsifiable only with respect to their
symbolic character.
- Tautologies like F=ma and 'white swan' are falsifiable with
respect to the real world realities to which they refer.
- The creationist tautological attack is on one label "survival
of the fittest" used to refer to evolution, not evolution itself.
el cid
> Here are some examples of tautologies:
>
> - false myth
> - a bachelor is an unmarried man
> - tomorrow is another day
> - Green baby swans are cygnets the colour of grass
Quibble the first: myths are not defined to be false.
False myth is not a tautology.
Mike Lyle
Agreed. "Myth" is one of those unhappy words with equally current proper
and debased senses.
--
Mike.
David Hare-Scott
non-technical but educated layman (tha's me) the tone and level seems right.
One problem that I noticed. I have snipped the rest to make it clearer.
This bit:
> Tautologies are True by definition and
> may be characterised as follows:
>
.....
> - not dependent on empirical testing (observations from the real
> world)
>
......
contradicts this bit
> Thus, being a tautology, does not immunize a
> statement from being falsified by observation.
>
I think I know what you are driving at but as it stands it's just a
contradiction.
David
Friar Broccoli
If this is my worst problem, I will be very surprised.
Friar Broccoli
Thanks, I will work out some way to fix this.
Friar Broccoli
> I hope that folks here who actually know what they are talking
> about, like Wilkin's, Ernest Major, and Harshman will find my
> effort worth their time to criticize.
I apologize for forgetting to include:
Richard Norman, Howard Hershey, Augray, and Perplexed in Peoria
(who seems to have disappeared) in the above list. No doubt
more apologies well be forthcoming.
J. J. Lodder
The friar is not clear in his mind on the disticttion
between mathematical equations and physical ones.
F = ma as an axiom in a mathematical formulation of Newton's theory
and F = ma as an economical description of thing observble
are entirely different things conceptually,
even though they look just the same.
(I'll try to come back to this point)
Jan
Jan
>
> David
J. J. Lodder
Darwin did nothing of the kind.
For him 'the fittest' were not merely 'those who survive'.
That meaning was given to it later,
by others who didn't want to understand the theory.
> Unfortunately, some people now focus on the phrase "the survival
> of the fittest" arguing that because it is a tautology, natural
> selection and hence all of the theory of evolution is a fraud.
> However, the words "survival of the fittest" do not by
> themselves define evolution, which includes other processes such
> as Mutation, Genetic Drift, and so on.. Rather, "survival of
> the fittest" is more like an advertising slogan or label,
> focusing attention on a key idea in the natural selection
> process. Here, note that for Darwin "The Survival Of The
> Fittest" was a synonym for, or subset of, "Natural Selection"
> yet no one argues that "Natural Selection" is a tautology.
'Differential survival' would be a neutral and much better term.
(to be continued)
Jan
ivar
tautology is, by definition, always true. Hence, it is logically
impossible to falsify a tautology. "All swans are white" was never a
tautology. It was always conceivable that non-white swans did exist
and, in fact, black swans do exist. Arguably, all equations derived
from a set of axioms are tautologies. But, this does not mean that
all equations, e.g., E=MC2, are tautologies. People had faith in
Newton's Law of Gravitation for centuries and it turned out to be
false. People, Poincare for example, have argued that F=ma is a
tautology. However, I believe the reason was that they viewed the
equation as a definition of force, not as a law of physics. (I could
be wrong about this.)
I've been thinking about the idea that the creationist version of
natural selection is a straw man. (They probably would not agree.)
It has occurred to me that this may not be best way to think about
this. We are dealing with two kinds of statements here:
a.) Logical statements, e.g., if A is statement that is true or false,
then the statement "A or not A" is a statement that is always true. A
tautology is a logical statement.
b.) Scientific statements, e.g., E=MC2 and Newton's Law of
Gravitation.
Our problem may be that they and we are conflating the two, that we
are jumping back and forth between the two kinds of statements without
realizing it. The result is confusion.
Creationists, for example, present the phrase "the survival of the
fittest" as a component of a tautology (which is a logical
statement). Evolutionists, on the other hand, think of "the survival
of the fittest" as a label for an important process in the theory of
evolution (which is a scientific statement).
When used in a logical statement, the word "fitness" functions as an
abstract symbol. In the theory of evolution, the word "fitness" might
refer to a collection of definitions of fitness, e.g., fitness due to
speed, fitness due to camouflage, etc. In science, the idea of
fitness can evolve. Biologists will want to preserve the idea that
fitness refers to survival. But they will expand this idea to
incorporate other factors. They are not constrained by its use in a
tautology.
Scientific statements are testable. Scientific statements refer to
the real world.
The only test for logical statements is whether they are logical.
I'm not sure where all this is going. And, the Scotch in my glass is
getting low. But, it may give some people some ideas on better ways
to organize the FAQ tautology page.
Ivar
J. J. Lodder
> has shown that genetic drift is a majour
> determinant of inherited characteristics.
Myday was better than jours?
Jan
Friar Broccoli
Yes, I would VERY much like more input on this point/issue.
The distinction between physical reality and the formulations
that people use to describe them is central to many of the points
I am trying to make.
>
> Jan
Friar Broccoli
> > I decided to start a new thread because backspace has invaded
> > the original here:
.
.
Perhaps I could change:
"Darwin unwittingly created the tautology problem when"
to something like:
"Darwin created the conditions for the tautology allegation when"
>
> > Unfortunately, some people now focus on the phrase "the survival
> > of the fittest" arguing that because it is a tautology, natural
> > selection and hence all of the theory of evolution is a fraud.
> > However, the words "survival of the fittest" do not by
> > themselves define evolution, which includes other processes such
> > as Mutation, Genetic Drift, and so on.. Rather, "survival of
> > the fittest" is more like an advertising slogan or label,
> > focusing attention on a key idea in the natural selection
> > process. Here, note that for Darwin "The Survival Of The
> > Fittest" was a synonym for, or subset of, "Natural Selection"
> > yet no one argues that "Natural Selection" is a tautology.
.
> 'Differential survival' would be a neutral and much better term.
I think I agree, however, I suspect that making this change would
require some extensive rewriting in order to introduce the "new" term
and make a clear transition from SoF and NS to 'Differential
survival'.
In my view, my proposal is already too long, and the more terms I
add and explain the longer it gets. Need to try the change and
see how it works.
Friar Broccoli
I agree with most of what you said above.
In my view the heart of the problem here is that there is
definitely a difference between tautologies like:
- bachelors are unmarried men
which are simple definitions
and
- mammals have hair
which like F=ma are descriptions of the properties
of external reality/objects.
I was dimmly aware of the problem as I wrote, but since
this is the first time I have looked at this issue I
could not put together my arguments and work out the
nuances of the classes of tautologies in the time needed.
I will try for something better next weekend.
If people have suggestions on how to deal with this issue,
I am all sensory organs.
Burkhard
Rather, "survival of
> the fittest" is more like an advertising slogan or label,
> focusing attention on a key idea in the natural selection
> process.
I would probably avoid the expression "advertising slogan" -
advertising is too close to propaganda, which is too close to "not
being quite truthful"
My take would be a bit like this:
Rather, "survival of the fittest" just flags up the _type_ of
explanation, or the argument scheme, that the theory will provide. It
indicates the bare conceptual skeleton of the theory, which then
requires to be fleshed out to have empirical content. "This
specific species X survived because it's members ran faster, had a
more beautiful plume or could eat a greater variety of food" are all
instantiations of the argument scheme that can be empirically tested.
If we would never or only very rarely find specific applications of
the scheme that withstand empirical testing, the concept "survival of
the fittest" would be discarded as useless.
<note: I think this point is worth making to deal with some of the
more elaborate objections. Someone might cite for instance a specific
claim, e.g. that species X survived because of Y, which later is
falsified. This is then used to argue that either this falsifies the
notion of survival of the fittest per se, or shows that "the ToE" is
immune from falsification. Instead, there are different ways in which
complex research projects can be revised>
I would also add something like this:
This is not a feature specific to the Theory of Evolution. Rather, we
find in all complex scientific theories a distinction between abstract
explanation schemes (the "potential models of the theory") and actual
empirical instantiations of these schemes tha can eb empirically
tested. (see e.g. W. Balzer , C.U. Moulines , J.D. Sneed: An
Architectonic for Science: The Structuralist Program Springer 1987)
<note: something like this is needed to prevent the accusation of
"special pleading" for the ToE. I proposed this specific cite because
no other approach has been as obsessed with "t-theoretical terms" (aka
tautologies) in scientific theories than them, and the book has
several examples form physics. The expressions "potential model" comes
from them too, feel free to drop if it is to technical/too out of
context)
>
> - repetition of meaning, using different and dissimilar words or
> symbols to effectively say the same thing twice.
I would drop this. It covers too many stylistic sins that have nothing
to do with tautologies. We can always make a logically valid argument
longer by unnecessarily repeating some premises. Pleonasm is another
example. Wikipedia claims that these are called tautologies by the
rhetorical tradition, but does not give a cite, and I don't can't
remember ever seen this expression used by the major writers on
rhetoric. Barring some good evidence that these stylistic
transgressions have historically been grouped together with
fallacious arguments, I would leave them out.
But we might want to include "question begging" and "petitio
principii" as ways people talk about tautologies.
>
> Karl Popper [1976: sect. 37] also had doubts about whether
> "Darwinism" was a testable scientific theory. According to
> Popper, any situation where species exist is compatible with
> Darwinian explanation, because if those species were not
> adapted, they would not exist. That is, Popper says, we define
> adaptation as that which is sufficient for existence in a given
> environment. Therefore, since nothing is ruled out, the theory
> has no explanatory power, for everything is ruled in.
>
> This is not true, as a number of critics of Popper have observed
> since (e.g., Stamos [1996] [note 1]).
I would add here: And Popper himself later withdrew this criticism
after more careful investigation of the theory of evolution. (K
Popper, "Natural Selection and the Emergence of Mind", Dialectica,
vol. 32, no. 3-4, 1978, pp. 339-355
>F=ma is of particular interest here because although it is a
>tautology, it has in fact been falsified. That is, it is not
>true in relativistic frameworks, a fact which has been
>observationally verified. Similarly, "white swan" was once
>thought to be a tautology, up until they found black ones in
>Australia. Thus, being a tautology, does not immunize a
>statement from being falsified by observation.
I'm not too sure about this, and would replace the word "falsified" by
"revised in the light of new observations". By definition, being a
tautology protects you from being falsified by observation that's so
to speak tautological. . But this still means that we might be
mistaken about what a tautology is. We arguably don't want to go too
deeply into the problem of the semantics of natural kinds (not the
least because of the unfortunate "kind" expression) and on rigid
designation and essentialism. But if in your classification scheme,
you explicitly define swans as "big white water birds that belong to
the queen", the observation of black swans does not falsify your
statement that all swans are black. Rather, it gives you a good
reason to revise your classification scheme. In this case, i supose we
see that these black birds share more features with our "white swan"
than with any other animal, in particular features we consider in
other contexts to be relevant to group them together. And we also
think that colour is really not that important. But there is nothing
logically necessary or inevitable in this, i would say.
Rather, I would describe it as an example of one of the several ways
in which science improves in response to new observation and data,
that is by developing better classification schemes that have a more
consistent fit which what we observe. This can mean that something
that we considered to be a defining feature of a thing becomes a
contingent, empirical feature of it. The original definition was not
so much wrong as useless or unhelpful.
>Darwinian theory rules out
> quite a lot. It rules out the existence of inefficient organisms
> when more efficient organisms are about.
I would possibly drop this first one. Someone could claim that
"efficient" is again only measured in terms of survival, an almost
synonymous replacement for "fittest".
One other thing ruled out by Darwinian theory: Species "die out" at
the same way individuals die, after a more or less fixed allotted
time. (I seem to remember that this theory was around at some point,
John might be able to clarify further)
a possible candidate would also be: no species ever goes extinct
(possibly important as this could be seen as a "predication" of some
theistic creation doctrines).
Ernest Major
<fd789650-4776-433e...@n11g2000yqb.googlegroups.com>,
Friar Broccoli <eli...@gmail.com> writes
You have to careful here
X is a bachelor -> X is an unmarried man: T
X is an unmarried man -> X is a bachelor: F, because of the existence of
widowers and divorced men.
>which are simple definitions
So bachelors are unmarried men is a tautology, but not a definition.
>
>and
>- mammals have hair
>which like F=ma are descriptions of the properties
>of external reality/objects.
>
>I was dimmly aware of the problem as I wrote, but since
>this is the first time I have looked at this issue I
>could not put together my arguments and work out the
>nuances of the classes of tautologies in the time needed.
>
>I will try for something better next weekend.
>If people have suggestions on how to deal with this issue,
>I am all sensory organs.
>
--
alias Ernest Major
John S. Wilkins
> One other thing ruled out by Darwinian theory: Species "die out" at
> the same way individuals die, after a more or less fixed allotted
> time. (I seem to remember that this theory was around at some point,
> John might be able to clarify further)
Orthogenesis and Aristogenesis. The idea that species are like
biological individuals with lifecycles has been around for yonks.
--
John S. Wilkins, Philosophy, University of Sydney
http://evolvingthoughts.net
But al be that he was a philosophre,
Yet hadde he but litel gold in cofre
tg
> I decided to start a new thread because backspace has invaded
> consequently it will soon be impossible to find anything in that
> thread.
>
> ______________________________________________________________
>
>
> ivar wrote:
>
> [snip]
>
> > Perhaps, you could write a paragraph or two describing what you think
> > should be in the FAQ tautology page relating to "SoF as a tautology."
> > You can steal my words or Darwin's if that helps.
>
> I made a stab at putting the tautology arguments into a couple
> of paragraphs, but found I couldn't do that sensibly without
> building a context, so I rebuilt the FAQ, steeling liberally
> mostly from you but also from pretty much everybody who
> has thus far contributed to the discussion.
Sorry, guys, but the simplest and the shortest way of dealing with
this happens to coincide with some input from backspace. Thankfully I
wrote this before seeing his post, but there it is. Anyway, this is a
layman's attempt to communicate with laypersons.
Insert here:
But this is not a problem.
ToE tells us that the genetic makeup of a population changes, or
species evolve, primarily through the process of Natural Selection.
Natural selection occurs in two ways, and to understand them we must
use the proper language.
1. Individuals that survive longer because of some genetic trait get
to reproduce more and pass on that genetic trait to the next
generation.
2. Individuals that attract more mates because of some genetic trait
get to reproduce more and pass on that genetic trait to the next
generation.
If we call those individuals in 1) "fitter", and the individuals in 2)
"sexier", then we would logically say that "Natural Selection occurs
through survival of the fittest, since they get to reproduce more", as
well as "Natural Selection occurs through more mating of the sexiest,
since they get to reproduce more".
Now, if we look at the language in this context, we see that the idea
of tautology doesn't *matter* here---if we say: "Natural Selection
occurs through survival of those who survive, since they get to
reproduce more.", it doesn't change the truth about natural
selection. Natural selection occurs because genetic differences allow
some individuals to reproduce more than others--- because, for
example, a zebra colt can run fast, or maybe because she has 'more
attractive stripes'.
Language structures like tautology, and circular definitions, only
matter if they affect---intentionally or not---how the reader
understands the sentence or paragraph where they are used. For
example, "Come to the mall today and you will get a free gift."
contains the tautological "free gift". But if you go to the mall, you
will still get a gift; the tautology hasn't changed the validity of
the statement.
The idea of falsifiability requires that all the small parts of a
theory or idea *that are necessary to the validity of the idea* be
subject to disproof. If we look at all such elements in Natural
Selection, we see that they are easily tested. We can map the genetic
distribution of a population, we can observe whether some individuals
survive longer or get more mates, and we can see if the genetic
distribution of the next generation is different as a result. The
phrase "survival of the fittest" is *irrelevant* to the scientific
process here.
End my version---again, I am aiming at the layman and trying to be
brief, consolidating what various people have said. I might also
modify your introduction but mostly to be shorter.
-tg
> logical or semantic a priori ...
>
> read more »
Ernest Major
<f5639deb-c967-46ce...@b14g2000yqd.googlegroups.com>,
Friar Broccoli <eli...@gmail.com> writes
>I made a stab at putting the tautology arguments into a couple of
>paragraphs, but found I couldn't do that sensibly without building a
>context, so I rebuilt the FAQ, steeling liberally mostly from you but
>also from pretty much everybody who has thus far contributed to the
>discussion.
I haven't been giving this the thought necessary for a significant
contribution, but I would like to suggest that it would be worth
breaking the issue down into different questions.
To whit
"Creationists sometimes present a claim that "survival of the fittest"
is a tautology as a purported argument against the theory of evolution.
This can be broken down into two claims - that "survival of a fittest"
is a tautology, and that this is a problem. So we wish to address two
different questions or groups or questions.
1) If "survival of the fittest" was a tautology would this be a problem
for the theory of evolution?
2) Is "survival of the fittest" a tautology. Note that the answer may be
different for Spencer's usage, for Darwin's usage, and for modern usage,
so it may be necessary to address each individually."
Answering the second question may be overkill, as the answer to the
first is negative, but there are sufficient ambiguities in the answer to
the first that maybe it should be addressed.
As has been mentioned, in logic, a tautology is a statement that is
unconditionally true. As such one would wonder why a creationist would
think that asserting that survival of the fittest is a tautology is a
persuasive argument against evolution. However, it often transpires that
the argument is not per se that it is tautologous, but that it is
tautologous, and therefore vacuous, circular, or unfalsifiable. (Are
there FAQs on these points we should be referring to.)
Some tautologies are problematic arguments - for example "if dualism is
true then dualism is true". This is a tautology. That it is a tautology
is not a problem; that it is a circular argument is. For example "a man
is a man" is true. This is a tautology. That it is a tautology is not a
problem. That it is vacuous is.
To change the subject a little, in the last thread El Cid Bivar objected
to me treating natural selection and survival of the fittest as synonyms
- both labels for the process of "differential reproductive success
causally correlated with hereditary traits". I think it is useful to
maintain a distinction between the process of natural selection, and the
theory of evolution by natural selection. But this is partly a question
of usage. I'm not aware that there's anything idiosyncratic about the
distinction I make, but then I would not necessarily be so aware;
however you mentioned that one of Darwin's chapter titles was "Natural
Selection, or Survival of the Fittest", which on the face of it is
treating them as synonyms.
--
alias Ernest Major
Steven L.
An algebraic equation, devoid of interpretation (semantics), cannot be
falsified. Indeed, it cannot even be meaningfully employed in mathematics.
Devoid of interpretation, F = m a is no more falsifiable than X = y z,
or r = s t, or any one of same structure without a supplied semantics.
In fact, without an interpretation, even the equals sign "=" is
meaningless. (Would intelligent aliens from another planet, though
scientifically far more advanced than humans, know what it means without
being told?)
In mathematical logic, we learn how to provide an interpretation
(semantics) for each term and operator in a mathematical statement,
that maps each term to its allowed set, and each operator to the axioms
that define it. To begin with, F, m, and a are considered by physicists
to be real numbers, and "=" to mean equality. The axioms of equality
are taken to be the Peano postulates for the equality relation.
Science provides interpretations that go further and ostensibly match up
with quantities observable in the real world. So they interpret F to
mean physical force, m to mean mass, etc. Then they assert that F = m a
accurately depicts the behavior of phenomena in the real world. But
that assertion can be falsified, and in fact the Theory of Relativity
falsified it for very high speeds and masses.
Electrical engineers freely work with complex numbers to describe
real-world phenomena, showing that it's highly important to get the
semantics well defined.
--
Steven L.
Email: sdli...@earthlinkNOSPAM.net
Remove the NOSPAM before replying to me.
Steven L.
Uh, that didn't start now, but long, long ago.
It's important to say something about the history of this tautology
argument, so that the reader understands that it's a quaint sophistry
that keeps getting recycled.
It didn't even start with Popper.
Martin Gardner had cited the tautology argument in his book "Fads and
Fallacies," published in 1956. The argument may well have been raised
from the moment OoS was published.
Finally, here are two references you can cite on the tautology problem:
I was trying to find out just who came up with this tautology argument
originally, and stumbled across these references that discuss it
directly but don't explain where it came from.
Steven L.
Scientists like Mayr recognized the need to address this issue, as far
back as the 1940s:
The tautology problem may go back even further.
Steven L.
Specifically, Wallace had reviewed his work and suggested that Darwin
adopt Herbert Spencer's phrase "survival of the fittest." The phrase was
originally coined by Herbert Spencer, NOT by Darwin (so much for
"Darwinism" meaning "survival of the fittest").
http://en.wikipedia.org/wiki/Herbert_Spencer
el cid
> To change the subject a little, in the last thread El Cid Bivar objected
> to me treating natural selection and survival of the fittest as synonyms
> - both labels for the process of "differential reproductive success
> causally correlated with hereditary traits". I think it is useful to
> maintain a distinction between the process of natural selection, and the
> theory of evolution by natural selection. But this is partly a question
> of usage. I'm not aware that there's anything idiosyncratic about the
> distinction I make, but then I would not necessarily be so aware;
> however you mentioned that one of Darwin's chapter titles was "Natural
> Selection, or Survival of the Fittest", which on the face of it is
> treating them as synonyms.
Perhaps to your dismay, I will treat this as an invitation
to repost one of my arguments.
I've put many things together here but address the question
of differentiating between evolution, natural selection and
survival of the fittest. The main thing missing is something
simple and clear to reaffirm that a tautological statement
within an argument does not make the whole argument a
tautology.
Tautology FAQ
A frequent criticism of evolution has been that it is
a tautology. This FAQ will address this issue in 3 ways.
(1) It will show that evolution is not a tautology.
(2) It will show that natural selection --- one but
only one of the mechanisms of evolution - is not a
tautology.
(3) It will show that the term _fitness_ has different
technical meanings in different formulations of natural
selection, and while some formulations define fitness
(definitions are usually tautologies) others
do not.
The short answer to the tautology criticism is then
that evolution is not just natural selection, natural
selection is not just “survival of the fittest” and
that even when you define fitness as reproductive
success, that doesn’t make natural selection or
evolution a tautology.
There are two examples of the tautology criticism
that this FAQ will address, not because they are
particularly good criticisms but because they are
common. This is the first. (the second is from Popper)
[quote]
The second prong of Darwin’s “theory” is
generally nothing but a circular statement:
Through the process of natural selection,
the “fittest” survive. Who are the “fittest”?
The ones who survive! Why look – it happens
every time! The “survival of the fittest”
would be a joke if it weren’t part of the
belief system of a fanatical cult infesting
the Scientific Community.
The beauty of having a scientific theory
that’s a tautology is that it can’t be
disproved. Evolution cultists denounce
“Creation Science” on the grounds that
it’s not “science” because it can’t be
observed or empirically tested in a laboratory.
Guess what else can’t be observed or empirically
tested? Evolution! (Godless: The Church of
Liberalism, pp. 212-213). [quote]
The critical fallacy in the above argument (for
this FAQ) occurs in the second quoted paragraph.
One “prong” of Darwin’s theory suddenly becomes
the whole theory of evolution. The bait and switch
probably sounds convincing to people who only
remember the “survival of the fittest” part of
evolution. But natural selection is not just
“survival of the fittest” and evolution is not
just natural selection so the attack is itself
a logical fallacy.
Key Concepts
As you can see, the typical criticism that evolution
is a tautology is based on confusing the relationship
between different things including fitness, natural
selection, evolution and perhaps even what a tautology
is and what a tautology implies. So it is time to
define the key terms and then expand on their
relationships.
Tautology (external links wiki,
Evolution
Natural Selection
Fitness and Survival of the Fittest
Q: What is a tautology?
A: Examples
All bachelors are unmarried men.
A: Tautologies defined
Stolen from http://members.iinet.net.au/~sejones/PoE/pe02phl3.html#lgclprblmstlgy
A tautology is a statement that is "true by definition,
true by the meanings of words, true by the use of
syntactical elements" but "give no information about
the world" (Fearnside & Holther, 1959, p.137). "It is
this lack of material content that is referred to when
it is said that such truth is tautological or trivial."
(Fearnside & Holther, 1959, p.137).
Q OK, so what?
Tautologies are fine as definitions, but not as testable
scientific statements-there can be nothing to test in a
statement true by definition.)" (Gould, 1978, p.40)
Q OK, yeah, and so what about Evolution. Is it a tautology?
A: First we have to break down what we mean by evolution
and in particular what we mean by Natural Selection and
and what we mean by Survival of the Fittest.
The theory of evolution is more than just Natural Selection.
Natural selection is one of the mechanisms working within
the theory of evolution. Natural Selection begins with a
set of observations about reproducing organisms and
develops some logical consequences. Survival of the
Fittest is one of the observations within Natural
Selection.
[Expand, briefly, evolution]
[modern synthesis, includes NS, incorporates population
genetics, includes natural history]
[Expand NS]
Observation 1 Populations of organisms tend to produce
more offspring than survive to reproduce in the next
generation.
Observation 2 Variation is usually observed to exist
in each generation.
Observation 3 Some of the variation produces individuals
with competitive advantages over their peers.
Observation 4 Some of these advantageous traits are
inheritable.
Deduction 1 Competition among peers will favor those
individuals with advantageous traits.
Deduction 2 Those individuals with advantageous traits
will tend to produce more offspring.
Deduction 3 Subsequent generations will have a higher
proportion of the inheritable traits that provide a
competitive advantage.
There are no tautologies in this formulation of
Natural Selection.
[Aside: I find it interesting that you can explain NS
in simpler terms, using a tautologous formulation
of SoF, making me wonder about the claims of tautologies
being useless. I do this below ]
Q What about Survival of the Fittest?
A Survival of the Fittest is the bumper-sticker version
of the theory of Natural Selection. It does not cover
all of the theory of evolution. It focuses on a
deduction 1 of the logical argument presented above
and assumes that the rest of it is obvious (which it
mostly is but not being explicit about obvious things
often leads to confusion). So another way to present
natural selection is to say:
A. Organisms show variation.
B. The fittest are more likely to survive to produce
more offspring. (Survival of the Fittest)
C. Fitness will increase in successive generation.
Q. Is that statement of Survival of the Fittest a Tautology?
A. Yes.
Q. Does that make the whole argument a tautology?
A. No. The whole argument is about the effect over
subsequent generations.
Q. But what about the first version of natural selection
that did not have a tautology?
A. We can reword if you are hung up about tautologies.
C'. 'The more likely to survive and produce more offspring'
will increase in subsequent generations.
This just substitutes equivalent terms: fittest and
'The more likely to survive and produce more offspring'
Using a technical definition of fitness makes the
language less cumbersome.
Q. Isn't that a problem if you define fitness that way?
A. No. In fact, population genetics has a formal
variable called fitness which is measured by the proportion
of a trait that survives in the next generation. So
it isn't a problem, it is part of turning the theory
of natural selection into a mathematical model.
Q. But if it is a tautology, isn't that bad?
A. Not if we are careful with the word _fitness_.
We are just getting a new meaning for this
word _fitness_ to take the place of many words.
It is a technical usage.
The confusing part is that there are already meanings
people use for the word fitness and in particular
the meaning people associate with physical fitness.
The physical fitness meaning is often a good match
to the intuitive sense of a reproductive advantage.
It is often used in examples of a faster rabbit
outrunning a fox or a stronger walrus gathering
a larger harem.
But being stronger and more muscular may not always
be the biggest advantage for an organism so sometimes
physically fit doesn't match to evolutionarily fit.
A simple example is that building muscles instead
of fat doesn't help if you need to survive through
a snowy winter with little food. Muscles consume
energy but fat provides it.
An important lesson about the technical definition
of fitness is that it depends on the environment
an organisms lives it and what competitive challenges
it faces.
Fitness is still a good word but everybody,
especially evolutionary biologists, needs to
be careful not to confuse the technical definition
of fitness with more casual meaning.
Q. But what did Darwin mean by fittest? Isn’t that the
Whole point?
A. It shouldn’t be. Scientific theories do not belong
to their authors, they ‘evolve’ to match new data.
However, you can mix things up some and change the
formulation of natural selection provided here
to bring survival of the fittest to be a prediction
rather than an observation. This may seem good
because people feel comfortable with simple ideas
like faster rabbits (or faster foxes) being more
fit. But simple ideas about what provides a
competitive advantage often fail to understand
the full combination of variables that result
in a competitive advantage. Is turning sharply
as important as running fast? Does running
faster make it harder to turn sharply?
Friar Broccoli
> <f5639deb-c967-46ce-8721-487664a95...@b14g2000yqd.googlegroups.com>,
> Friar Broccoli <elia...@gmail.com> writes
.
I have other problems (including the fact that I am receiving
more useful input than will fit in my tiny little brain), but
right now this problem and its variants is the one that most
concerns me.
One problem is that you say: "in logic, a tautology is" but I'm pretty
sure that "in rhetoric, a tautology is" has (a) different ending(s).
I think I've also seen gramatical definitions.
I note that if I take your definition then:
- F=ma (yes Steven L, I agree, I just want to be brief) and
- web footed duck
are not tautologies, and I have no doubt that there are people
out there who would rather die than concede the contrary. Do I
need to resolve the issue of what is or is not a tautology?
My view (at present) is that I need to briefly and clearly break
down the POSSIBLE categories of what might be considered a
tautology, and then show that "survival of the fittest" belongs
in the category of those tautologies/non-tautologies (let the
reader decide) that can be falsified.
> As such one would wonder why a creationist would
> think that asserting that survival of the fittest is a tautology is a
> persuasive argument against evolution. However, it often transpires that
> the argument is not per se that it is tautologous, but that it is
> tautologous, and therefore vacuous, circular, or unfalsifiable. (Are
> there FAQs on these points we should be referring to.)
>
> Some tautologies are problematic arguments - for example "if dualism is
> true then dualism is true". This is a tautology. That it is a tautology
> is not a problem; that it is a circular argument is. For example "a man
> is a man" is true. This is a tautology. That it is a tautology is not a
> problem. That it is vacuous is.
Breaking down POSSIBLE tautologies by vacuous, circular,
unfalsifiable and falsifiable looks (at this moment) like a
good path.
.
> To change the subject a little, in the last thread El Cid Bivar objected
> to me treating natural selection and survival of the fittest as synonyms
> - both labels for the process of "differential reproductive success
> causally correlated with hereditary traits". I think it is useful to
> maintain a distinction between the process of natural selection, and the
> theory of evolution by natural selection. But this is partly a question
> of usage. I'm not aware that there's anything idiosyncratic about the
> distinction I make, but then I would not necessarily be so aware;
> however you mentioned that one of Darwin's chapter titles was "Natural
> Selection, or Survival of the Fittest", which on the face of it is
> treating them as synonyms.
Since this is a semantic rather than substantive issue, I see
less than no value in breaking with Darwin's apparently
intended usage.
Ernest Major
<c6ffbecd-9870-4ca2...@t13g2000yqt.googlegroups.com>,
Friar Broccoli <eli...@gmail.com> writes
Rather than try to define the meaning in rhetoric, I'll refer you to
Wikipedia.
* http://en.wikipedia.org/wiki/Tautology_(rhetoric)
(The 2nd definition given there blurs the distinction between rhetorical
and logical tautologies).
I expect that the grammatical and rhetorical definitions of tautology
are much the same.
>
>I note that if I take your definition then:
>- F=ma (yes Steven L, I agree, I just want to be brief) and
>- web footed duck
>are not tautologies, and I have no doubt that there are people
>out there who would rather die than concede the contrary. Do I
>need to resolve the issue of what is or is not a tautology?
You may find it difficult to demonstrate that "survival of the fittest"
is not (or is) a tautology without defining what a tautology is.
(However, once you get away from formal logic, the definition of
tautology, like much else in English, develops fuzzy edges.)
Two points on this -
1) If subsequent or current usage differs from Darwin's then this would
overrule Darwin.
2) We can't safely deduce Darwin's usage just from the chapter title.
That said, I expect, but do not know, that most subsequent and current
usage, as well as Darwin's, treat them as synonyms, or a close
approximation thereto.
--
alias Ernest Major
Eric Root
>
> read more »
Good explanation.
Eric Root
Mark Isaak
> [big snip]
> Here are some examples of tautologies:
>
> - false myth
Note that one important definition of myth is "sacred story", with
absolutely no requirement that it be false. I have seen some myths, such
as a myth about enemies being destroyed by a brush fire, which are
plausible and perhaps true. Thus "false myth" is not a tautology.
--
Mark Isaak eciton (at) earthlink (dot) net
"It is certain, from experience, that the smallest grain of natural
honesty and benevolence has more effect on men's conduct, than the most
pompous views suggested by theological theories and systems." - D. Hume
Friar Broccoli
> On Aug 16, 11:45 pm, Friar Broccoli <elia...@gmail.com> wrote:
>
> Rather, "survival of
>
> > the fittest" is more like an advertising slogan or label,
> > focusing attention on a key idea in the natural selection
> > process.
>
> I would probably avoid the expression "advertising slogan" -
> advertising is too close to propaganda, which is too close to "not
> being quite truthful"
Yes, "label" is probably better.
> My take would be a bit like this:
>
> Rather, "survival of the fittest" just flags up the _type_ of
> explanation, or the argument scheme, that the theory will provide. It
> indicates the bare conceptual skeleton of the theory, which then
> requires to be fleshed out to have empirical content. "This
> specific species X survived because it's members ran faster, had a
> more beautiful plume or could eat a greater variety of food" are all
> instantiations of the argument scheme that can be empirically tested.
> If we would never or only very rarely find specific applications of
> the scheme that withstand empirical testing, the concept "survival of
> the fittest" would be discarded as useless.
Lodder in his discussion of my (miss)use of F=ma pointed out that
these letters are just meaningless variables until you plug in
real world values. I think I can make your point here by
making that parallel with SoF (W_abs_ = N_after_/N_before_)
Probably worth doing because it tightens the link between
physics and TOE while further reinforcing the operation of
tautologies on symbols as opposed to real events.
> <note: I think this point is worth making to deal with some of the
> more elaborate objections. Someone might cite for instance a specific
> claim, e.g. that species X survived because of Y, which later is
> falsified. This is then used to argue that either this falsifies the
> notion of survival of the fittest per se, or shows that "the ToE" is
> immune from falsification. Instead, there are different ways in which
> complex research projects can be revised>
I cannot see that this type of "science keeps changing" argument
is even addressed, let alone solved by the foregoing. At
bottom biology is such a complete mess that it is easy for people
to make up false rules and then find some evidence to defend
them.
> I would also add something like this:
>
> This is not a feature specific to the Theory of Evolution. Rather, we
> find in all complex scientific theories a distinction between abstract
> explanation schemes (the "potential models of the theory") and actual
> empirical instantiations of these schemes tha can eb empirically
> tested. (see e.g. W. Balzer , C.U. Moulines , J.D. Sneed: An
> Architectonic for Science: The Structuralist Program Springer 1987)
> <note: something like this is needed to prevent the accusation of
> "special pleading" for the ToE. I proposed this specific cite because
> no other approach has been as obsessed with "t-theoretical terms" (aka
> tautologies) in scientific theories than them, and the book has
> several examples form physics. The expressions "potential model" comes
> from them too, feel free to drop if it is to technical/too out of
> context)
Hmm, "potential model" looks like it might be useful since
again it can tie F=ma to SoF.
> > - repetition of meaning, using different and dissimilar words or
> > symbols to effectively say the same thing twice.
>
> I would drop this. It covers too many stylistic sins that have nothing
> to do with tautologies. We can always make a logically valid argument
> longer by unnecessarily repeating some premises. Pleonasm is another
> example. Wikipedia claims that these are called tautologies by the
> rhetorical tradition, but does not give a cite, and I don't can't
> remember ever seen this expression used by the major writers on
> rhetoric. Barring some good evidence that these stylistic
> transgressions have historically been grouped together with
> fallacious arguments, I would leave them out.
I am inclined to go the other way and suggest many definitions
because:
1- people are unlikely to agree with any definition we try to
enforce.
2- By suggesting several different definitions the boundary
lines between the definitions and thus their meaning will
become clearer to the reader, who's understanding of what a
tautology is will almost always be hazy.
3- In almost all arguments, creationists (I believe
unintentionally) move from one meaning of a word to another.
A reader who is aware of two or more possible meanings of
tautology will find it easier to spot such moves.
> But we might want to include "question begging" and "petitio
> principii" as ways people talk about tautologies.
When looking up "petitio principii" I found this delightful
example which I may add to my list of tautologies (as an example
of a circular reasoning "tautology"):
"Women write the best novels because men do not write novels as
well."
which I may oppose to something like:
"The fastest gazels are rarely eaten because they more easily
escape preditors"
although I clearly need something more similar to make it work.
Since as the author states:
"A statement cannot prove itself. A premise must have a
different source of reason, ground or evidence for its truth
from that of the conclusion."
I may point out that speed is an independent source that permits
not being eaten/survival.
.
> > Karl Popper [1976: sect. 37] also had doubts about whether
> > "Darwinism" was a testable scientific theory. According to
> > Popper, any situation where species exist is compatible with
> > Darwinian explanation, because if those species were not
> > adapted, they would not exist. That is, Popper says, we define
> > adaptation as that which is sufficient for existence in a given
> > environment. Therefore, since nothing is ruled out, the theory
> > has no explanatory power, for everything is ruled in.
>
> > This is not true, as a number of critics of Popper have observed
> > since (e.g., Stamos [1996] [note 1]).
.
> I would add here: And Popper himself later withdrew this criticism
> after more careful investigation of the theory of evolution. (K
> Popper, "Natural Selection and the Emergence of Mind", Dialectica,
> vol. 32, no. 3-4, 1978, pp. 339-355
I don't know whether this process will result in any other
changes, but I have no doubt this will be added to the FAQ.
>> F=ma is of particular interest here because although it is a
>> tautology, it has in fact been falsified. That is, it is not
>> true in relativistic frameworks, a fact which has been
>> observationally verified. Similarly, "white swan" was once
>> thought to be a tautology, up until they found black ones in
>> Australia. Thus, being a tautology, does not immunize a
>> statement from being falsified by observation.
> I'm not too sure about this, and would replace the word
> "falsified" by "revised in the light of new observations".
Two points:
- I might change "being a tautology" to something resembling
"tautologies having the same form as SoF" are not immunized
from being falsified (actually I expect to be doing a
complete rewrite using a range of possible definitions some
of which are falsifiable)
- The core claim is that SoF is unfalsifiable as a tautology,
consequently I want to retain the idea of falsifiability in
order to retain the thread of the argument. If I use another
word like "revised" the reader will fail to make the link.
> By definition, being a
> tautology protects you from being falsified by observation that's so
> to speak tautological. . But this still means that we might be
> mistaken about what a tautology is. We arguably don't want to go too
> deeply into the problem of the semantics of natural kinds (not the
> least because of the unfortunate "kind" expression) and on rigid
> designation and essentialism.
Alternatively we could try to confuse them into submission by
summing up with a discussion of analytic and synthetic statements.
> But if in your classification scheme, you explicitly define
> swans as "big white water birds that belong to the queen", the
> observation of black swans does not falsify your statement
> that all swans are black. Rather, it gives you a good reason
> to revise your classification scheme. In this case, i supose
> we see that these black birds share more features with our
> "white swan" than with any other animal, in particular
> features we consider in other contexts to be relevant to group
> them together. And we also think that colour is really not
> that important. But there is nothing logically necessary or
> inevitable in this, i would say.
The force of the swan example comes from its historical
context. At one time being white really was part of the
definition of swan. Just as F=ma expressed a fundamental
universal law. Evidence changes swanness, and the
laws governing physics and as well as evolution.
Are they tautologies - maybe, maybe not, either
way these cases change in the face of evidence, despite
anybody's definitions.
> Rather, I would describe it as an example of one of the several ways
> in which science improves in response to new observation and data,
> that is by developing better classification schemes that have a more
> consistent fit which what we observe. This can mean that something
> that we considered to be a defining feature of a thing becomes a
> contingent, empirical feature of it. The original definition was not
> so much wrong as useless or unhelpful.
>
> >Darwinian theory rules out
> > quite a lot. It rules out the existence of inefficient organisms
> > when more efficient organisms are about.
>
> I would possibly drop this first one. Someone could claim that
> "efficient" is again only measured in terms of survival, an almost
> synonymous replacement for "fittest".
I completely disagree with this:
"efficient" refers to doing more with the same resources or
the same with fewer resources. Indeed, it is such a clear
example of how fitness differs from survival at the level of
principle that I will make explicit reference to it. (I can
really work with this by tying it to things like intelligence)
This may sound like sarcasm (but it definitely isn't): I'm
REALLY glad you brought this to my attention.
I just looked at this again on the reread.
I am REALLY REALLY happy about this.
> One other thing ruled out by Darwinian theory: Species "die out" at
> the same way individuals die, after a more or less fixed allotted
> time. (I seem to remember that this theory was around at some point,
> John might be able to clarify further)
I find this idea both too fuzzy and too like assuming our
conclusion in this context.
> a possible candidate would also be: no species ever goes extinct
> (possibly important as this could be seen as a "predication" of some
> theistic creation doctrines).
Thanks for your comments, they were much appreciated.
Friar Broccoli
> On Sun, 16 Aug 2009 15:45:00 -0700, Friar Broccoli wrote:
> > [big snip]
> > Here are some examples of tautologies:
>
> > - false myth
>
> Note that one important definition of myth is "sacred story", with
> absolutely no requirement that it be false. I have seen some myths, such
> as a myth about enemies being destroyed by a brush fire, which are
> plausible and perhaps true. Thus "false myth" is not a tautology.
Well, if this is your only criticism of my draft, I will take that as
a vote for it. Personally, I'm with the folks that are attacking my
sloppy (non)definition of tautology.
Thanks
el cid
> "The fastest gazels are rarely eaten because they more easily
> escape preditors"
This is an important type of claim.
Where it is really really important is that it is something
people think they know which very well may not be so.
We want to think the above is true and want to think we
understand natural selection. It makes a trivial sense.
But is it true? Do you have any idea what fraction of
gazelles are caught by what type of predators? Is more
alert really a bigger deal? What good is fast when
lion 1 flushes the gazelle into lion 2 hiding ahead
in the bush? If we mean the Thompson's Gazelle, one
of their major predators is the cheetah. They are
not faster than the cheetah but make quicker turns.
More than half are probably harvested as juveniles
where faster genes have not yet manifested.
This all goes to what the heck fitness means.
Natural selection seems so simple that people think
they understand it but most probably don't or
even if they do they over simplify to the point
of distortion.
It certainly is true that something like being
faster than their fellows yields a competitive
advantage for some gazelles. over others. In
form the theory of natural selection is right.
But it is so much more complicated that our
simple notions of "fastest" being "fittest".
And if we are going to write a FAQ about whether
or not survival of the fittest is or is not
a tautology we have to be better at understanding
fitness than is typically the case.
John S. Wilkins
> Steven L. wrote:
> > Friar Broccoli wrote:
> >> I decided to start a new thread because backspace has invaded
> >> the original here:
> >>
> >>http://groups.google.com/group/talk.origins/browse_frm/thread/ee571605fb
> >>ebcd8b
> >>
> >> consequently it will soon be impossible to find anything in that
> >> thread.
> >>
> >> ___________________________
> >>
> >> On Aug 16, 1:32 am, in
> >> http://groups.google.com/group/talk.origins/msg/ca9b9c6f41842004
> >> ivar wrote:
> >>
> >> [snip]
> >>
> >>> Perhaps, you could write a paragraph or two describing what you think
> >>> should be in the FAQ tautology page relating to "SoF as a tautology."
> >>> You can steal my words or Darwin's if that helps.
> >>
> >> I made a stab at putting the tautology arguments into a couple
> >> of paragraphs, but found I couldn't do that sensibly without
> >> building a context, so I rebuilt the FAQ, steeling liberally
> >> mostly from you but also from pretty much everybody who
> >> has thus far contributed to the discussion.
> >>
> >> I hope that folks here who actually know what they are talking
> >> about, like Wilkin's, Ernest Major, and Harshman will find my
> >> effort worth their time to criticize. The writing needs more
> >> work too, but first the errors need to be squeezed out.
> >>
> >> Here's my effort.
> >> ___________________________
> >>
> >> Summary: The claim that evolutionary theory is unscientific or
> >> unfalsifiable because it is a tautology rests on a
> >> misrepresentation of, and focus on, the expression "Survival of
> >> the Fittest" as well as a misunderstanding of the properties of
> >> a tautology.
> >>
> >> Darwin unwittingly created the tautology problem when, in the
> >> fifth edition of his "On the Origin of Species," he changed the
> >> title of the fourth chapter from "NATURAL SELECTION" to "NATURAL
> >> SELECTION; OR THE SURVIVAL OF THE FITTEST." He wrote that he
> >> did this because "Several writers have misapprehended or
> >> objected to the term Natural Selection" on the basis that nature
> >> can't "select" in the way that man can "select".
> >>
> >> Unfortunately, some people now focus on the phrase "the survival
> >> of the fittest" arguing that because it is a tautology,
> >
> > Uh, that didn't start now, but long, long ago.
> >
> > It's important to say something about the history of this tautology
> > argument, so that the reader understands that it's a quaint sophistry
> > that keeps getting recycled.
> >
> > It didn't even start with Popper.
>
> Scientists like Mayr recognized the need to address this issue, as far
> back as the 1940s:
>
> http://tinyurl.com/nf2bgw
>
> The tautology problem may go back even further.
Oh, it does. I have seen similar complaints as early as the 1860s, but I
don't have the cites right now. If I can find them I will. Peirce makes
the point that Darwinian theory is a logical system in 1877.
John S. Wilkins
The clue as to why NS is not a tautology when used as an explanation is
exactly that point - the theorem[s] need to be interpreted. Used another
way: f=ms is a tautology (it is true by definition). When used to
explain why a given body is accelerating, it is not.
We need to distinguish several things that get called tautologies:
1. Definitional tautologies; bachelors are unmarried males.
2. Logical tautologies: the RHS is formally implied by the LHS of the
equation
3. Mathematical tautologies: terms either side of an equals sign are
coterminous
Definitional tautologies explain nothing but what is meant by the
defined term. Logical tautologies are implications of theorems or
axioms. They explain nothing but unravel what may be otherwise
unrealised in a set of premises. Mathematical tautologies are basically
your garden variety equations, and when interpreted, they are
explanations of one side's term by the other side's terms. For instance,
the ideal gas law PV=nRT explains why temperature and pressure covary,
although this is a simple tautology. When you interpret P as pressure,
measured in a physical manner, V as volume, measured in a physical
manner, and T as temperature, measured in a physical manner, n as the
number of gas molecules, and R as the gas constant for each gas, you
have an explanation.
The Price equation of natural selection is
wDELTAz = cov(wi, zi)+E(wi,DELTAzi)
The Wiki article <http://en.wikipedia.org/wiki/Price_equation > states,
correctly:
"Price's equation is, importantly, a tautology. It is a statement of
mathematical fact between certain variables, and its value lies in the
insight gained by assigning certain values encountered in evolutionary
genetics to the variables. For example, the statement "if every pair of
birds has two offspring, then among ten pairs of birds there will be
twenty offspring" is a tautology. It doesn't really impart any new
information about birds so much as it organizes our concepts about birds
and their offspring. The Price equation is much more sophisticated than
the above statement, but at its core, it too is a mathematically
provable tautology."
It is a mathematical tautology, which we use to compute what will happen
under physically realisable circumstances.
ivar
> A simple version of the so-called 'tautology argument' is this:
>
> - Through the process of natural selection, the 'fittest' survive.
>
> - Who are 'fittest'? The ones who survive.
>
> - Thus natural selection merely asserts that those who
> survive survive, a tautology. It just says the same thing twice.
>
> - As a tautology, it cannot be tested because it cannot be
> false. Hence, natural selection and thus the theory of
> evolution are not scientific. Thus, the proponents have leapt
> from asserting that the phrase 'Survival of the Fittest' is a
> tautology to the wider claim that 'evolution' as a whole is
> not a scientific theory.
>
> In order to understand the argument it is useful to ask, what is
> meant by 'tautology'. Tautologies are True by definition and
> may be characterized as follows:
>
> - repetition of meaning, using different and dissimilar words or
> symbols to effectively say the same thing twice.
> - true by the meanings of words, true by the use of syntactical
> elements
> - not dependent on empirical testing (observations from the real
> world)
A few comments:
The creationists are not really claiming that Darwin's words are a
tautology because he was too wordy or that he was repeating himself
unnecessarily. The words "It just says the same thing twice" probably
should be deleted. (Note that the original author of these words was
me.) It is desirable to minimize references to the "repetition of
meaning" version of tautology because it is not the real issue. They
only complicate the discussion. Perhaps a sentence saying that this
version of tautology is not the real issue would be helpful.
Some quotes from Henry Morris (Henry Morris, ed. 1985: Scientific
Creationism, Master Books):
"Creationists have long argued that natural selection has no
predictive value and thus is a mere tautology, stating the obvious
fact that organisms that "survive" are thereby decreed to have been
the "fittest," but it reveals nothing whatever about how they evolved
in the first place." page viii
"Evolution is dogma incapable of refutation." page 6
"A theory which incorporates everything really explains nothing! It
is tautologous. Those who survive in the struggle for existence are
the fittest because the fittest are the ones who survive." page 7
Another quote from Ann Coulter (page 213 of her "Godless" book):
"The beauty of having a scientific theory that's a tautology is that
it can't be disproved. Evolution cultists denounce 'Creation Science'
on the grounds that it's not 'science' because it can't be observed or
empirically tested in a laboratory. Guess what else can't be observed
or empirically tested? Evolution!"
I interpret these remarks to mean that they do not regard tautologies
as inherently bad, but rather, that tautologies are bad because they
can't be tested. Tautologies that are definitions are presumably OK.
Arguably, the phrase "the survival of the fittest" is a tautology
because it was really intended to be a definition of "fittest" or, at
least, to suggest the definition of fitness.
In any case, there is nothing in the phrase "the survival of the
fittest" or in the definition of tautology that precludes Darwin or
anyone else from particularizing fitness to a specific situation in
which fitness is testable. In fact, that is what scientists are
expected to do and do do.
Note that no scientific law or theory (or hypothesis, for that matter)
can be tested as a general concept. Only specific instances can be
tested. For example, you cannot test Newton's Law of Gravitation as
an isolated concept. You can only test specific instances, e.g., when
it is used to predict the orbit of Mercury in our solar system. See
the Duhem-Quine thesis article in the Wikipedia for more information.
Ivar
Friar Broccoli
As a result of comments by Burkhard I stumbled across a
circular reasoning "tautology":
"Women write the best novels because men do not write novels as well."
would this fit into the class of Logical tautologies?
> John S. Wilkins, Philosophy, University of Sydneyhttp://evolvingthoughts.net
> But al be that he was a philosophre,
> Yet hadde he but litel gold in cofre- Hide quoted text -
>
> - Show quoted text -
Friar Broccoli
In one of my replies to Burkhard I mistakenly referenced JJ Lodder as
the author of the above (very useful) comments by you.
My apologies
Friar Broccoli
I completely agree with everything in the above.
The problem is that this FAQ is about the tautology claim
and references to other issues must be as brief and CLEAR
as is possible.
Anyway maybe in a couple of weeks (or months) we will be
close enough to a finished version of this FAQ that we
can start picking away at some of the secondary examples
to insure that they are not too misleading.
backspace
> We need to distinguish several things that get called tautologies:
>
> 1. Definitional tautologies; bachelors are unmarried males.
From: "Is Natural Selection a tautology"
{{{
<pre>
There are two different usages of the word "tautology". One is
classical and refers to redundancies in expressions, e.g., "an
unmarried bachelor". The "unmarried" is redundant because a bachelor
is unmarried by definition. The other usage is much more modern and
apparently is due to Wittgenstein. It refers to propositions that are
true by virtue of their logical form irrespective of the truth or
falsity of the variables contained within the proposition. Thus,
according to this usage, "A or ~A" is a tautology.
The difficulty (and it is a real one) is that the principle of natural
selection can be formulated both in tautological and non-tautological
forms depending on how fitness is defined. The error of logic is to
define natural selection tautologically and then argue for its
empirical content.
Richard Harter, c...@tiac.net
http://www.tiac.net/users/cri
</pre>
}}}
=== post 17 ===
Richard Harter:
"Natural selection" is not a self contained expression; it is a label
for a description of a process. When you unpack the description you
run into a difficulty with the concept of fitness. If you define
fitness as reproductive fitness (as measured by actual reproductive
success) then the definition of natural selection is circular. If you
define fitness in terms traits which "ought" to be superior then it is
not circular.
>The fact that creationists like to raise this red herring simply indicates
>their lack of relevant arguments.
That is as it may be. It remains that the formulating the principle
of natural selection in a non-tautological form is a task with serious
difficulties.
=== post 18 ===
[[HersheyhPragmatics]]
Howard misquoted him:
> "Natural selection" is not a self contained expression; it is a label
> for a description of a process. When you unpack the description you
> run into a difficulty with the concept of fitness. If you define
> fitness as reproductive fitness (as measured by actual reproductive
> success) then the definition of natural selection is circular.
'''WHAT MATTERS TO THE CONCEPT OF NATURAL SELECTION''':
The success of one group relative to another group with a different
phenotype does matter to the concept of natural selection.
''Fitness = measured reproductive success of a group is a tautology in
the same way that every definition is a tautology.''
==== post18 cont NS IS DEFINED ====
Howrard defined NS:
And if you have a comparison that shows no difference
in fitness of the two groups you examine (that is fitness
(reproductive success) of group A/fitness B =1), you won't have
natural selection occurring there either.
For natural selection you need fitness A/fitness B to be significantly
different from 1. In
fact, that is not a bad definition of natural selection if you want a
nice short one:
natural selection is defined as and occurs when the measured
reproductive success of intraspecies variants with phenotype
A/ measured reproductive success of variants with phenotype B in the
same environment is significantly different from 1. Which phenotype
is fitter is determined by the direction of the difference. Of
course, as all good definitions should be, mine is a tautology, as
indicated by the = sign.
==== When does Natural selection occur ====
I agree that the term 'fitness' is used for the directly measureable
quantity 'reproductive success'. But I have no problem with that
being a tautology, since it is a definition of a specific calculated
quantity. But absolute 'reproductive success' or 'fitness', _per se_,
tells us nothing about whether natural selection is occurring. Only
*differential* reproductive success does.
==== What is 'fitness' used for ? ====
I agree that the term 'fitness' is used for the directly measurable
quantity 'reproductive success'. But I have no problem with that.
==== How is reproductive success measured ? ====
??
==== What is absolute fitness ? ====
=== Post 19 Harter ===
==== Fitness is comparative ====
Er, Howard, nobody was talking about "absolute fitness" except you.
'''It is understood that fitness is comparative.''' The question at
hand is whether natural selection '''defined''' in terms of measured
relative reproductive success is tautological. You seem to agree.
==== What is Absolute Reproductive Success ? ====
Now here I have no notion of what you mean by "absolute reproductive
success". What on Earth are you talking about.
==== Claim of Darwinian theory ====
The issue at hand is that natural selection as propounded by Darwin
and as regularly treated in evolutionary theory selects for
adaptation, fitness on a priori grounds of superior functionality.
This is a major claim of Darwinian theory.
The difficulty here is with arguing on one hand that "fitness" is
synonymous with whatever happens and on the other that "fitness" is
adaptive.
=== Notes ===
==== Claim of Darwinian theory ====
'''Richard''':
Darwinian theory really is about the natural selection of traits in
populations by virtue of
the superior fitness of the traits.
''' Harter ''':
The issue at hand is that natural selection as propounded by Darwin
and as regularly treated in evolutionary theory selects for
adaptation, fitness on a priori grounds of superior functionality.
This is a major claim of Darwinian theory.
The difficulty here is with arguing on one hand that "fitness" is
synonymous with whatever happens and on the other that "fitness" is
adaptive.
=== Post 20 Howard ===
==== Fitness that is relevant to natural selection ====
The fitness that is relevant to natural selection, however, is
'relative fitness', where
the fitness of a subgroup is compared to either that of a
phenotypically different subgroup or to the mean population fitness
(usually by dividing the subgroup fitness by mean population fitness
and normalizing all values to the case with highest 'relative
fitness'). If there is no significant difference in relative
fitnesses, there is no selection going on that can distinguish between
these phenotypes
==== When does natural selection not happen ====
What that means is that natural selection is *not* going on when there
is no significant *difference* in measured fitness.
==== Relationship between phenotype and reproductive success - RS
====
Of course, one still has the responsibility to present an argument
that the correlational
relationship between phenotype and differential reproductive success
is causal rather than casual; that the specified phenotype is the
reason for the differential reproductive success.
==== Fitness is measured as whatever happens ====
"Fitness", _per se_, is indeed measured as whatever happens (that is,
one measures reproductive success empirically). But it is 'relative
fitness' and not the directly measured 'fitness' that produces the
significant correlation between different phenotypes and greater
reproductive success that is required to make the claim that natural
selection has occurred. Further evidence, of course, is required to
demonstrate what it is about thsee correlations that is causal.
'Adaptive' is *defined* as those phenotypic features that result in
the most (reproductively) success in a particular environment. I
certainly
think it would make little sense to call such features "maladaptive",
as that would run counter to most people's notions of what "success"
or "beneficial" mean when you look at life. One can always argue that
the 'goal' of life ought not to be maximal reproductive success, but
that is a religious argument that doesn't seem to apply to, say,
insects, but is
*certainly* one that humans can and do consider for themselves.
=== Post 20 Richard Wein ===
==== "natural selection" *is* an expression. ====
In this sense, "natural selection" *is* an expression.
==== Is the term NS tautological or the definition of it ? ====
Perhaps what you're getting at is that I only considered whether the
term
"natural selection" is tautological, and not whether the *definition*
of
that term is tautological. That would be a good point, and I'll deal
with it
below. First we need a definition of "natural selection".
==== Definition of natural selection by Richard Wein ====
==== What is the best definition of natural selection ? ====
* >When you unpack the description you
* >run into a difficulty with the concept of fitness.
So, I guess you're defining "natural selection" as "survival of the
fittest". I'm not sure this is the best definition, but let's go with
it.
==== Tautological expressions and propositions ====
* >There are two different usages of the word "tautology". One is
* >classical and refers to redundancies in expressions, e.g., "an
* >unmarried bachelor". The "unmarried" is redundant because a
bachelor
* >is unmarried by definition. The other usage is much more modern
and
* >apparently is due to Wittgenstein. It refers to propositions that
are
* >true by virtue of their logical form irrespective of the truth or
* >falsity of the variables contained within the proposition. Thus,
* >according to this usage, "A or ~A" is a tautology.
This is the same distinction that I made, between a tautological
*expression* and a tautological *proposition* (or assertion), e.g.
between
"an unmarried bachelor" and "all bachelors are unmarried".
The tautological *expression* ("an unmarried bachelor") contains a
redundant word ("unmarried"), but has meaning and can be used to form
a
meaningful proposition, e.g. "John is an unmarried bachelor". This
proposition is *not* a tautology--it gives us real information about
John,
albeit in an unnecessarily verbose manner.
The tautological *proposition* ("all bachelors are unmarried"), on the
other
hand, gives us no information that is not already contained in the
definition of the word "bachelor".
Similarly, "survival of the fittest" may well be a tautological
expression,
but this does not deprive it of meaning.
>The difficulty (and it is a real one) is that the principle of natural
>selection can be formulated both in tautological and non-tautological
>forms depending on how fitness is defined. The error of logic is to
>define natural selection tautologically and then argue for its
>empirical content.
I assume that, by "empirical content", you mean empirical support for
a
proposition. You cannot have empirical support for an expression or
definition, and the empirical data are not necessarily *contained* in
the
proposition.
So what proposition are you referring to here? Presumably you're
referring
to the proposition that natural selection occurs. But this proposition
is
not, in itself, an interesting or controversial one, so it's not
important
whether it's tautological or not.
The interesting proposition is that natural selection plays a
significant
role in evolution. And this proposition is non-tautological even if
the
expression "natural selection" is tautologous. Unpacking the
proposition, we
get: "the tendency to reproductive success of those with the greatest
inherited propensity for reproductive success plays a significant role
in
evolution". The first 10 words of this proposition are redundant, as
we
could just as well write: "inherited propensity for reproductive
success
plays a significant role in evolution". But the fact that part of the
proposition is redundant does not make the proposition itself a
tautology.
Thus, the issue of tautology of "natural selection" only arises in the
context of:
* (a) the possible tautology of a proposition which is of no
interest; or
* (b) the possible tautology of an expression, and I've shown that
tautology
in an expression does not deprive it of meaning.
I therefore stand by my assertion that arguments about the possible
tautological nature of "natural selection" are nothing but a red
herring
=== Post 22 richard harter ===
==== Fitness of individuals and fitness of traits must not be confused
====
==== What difference between fitness of individuals, traits and
intrinsic fitness ? ====
I appreciate your qualms. May I point out that it is easy to confuse
fitness of individuals and fitness of traits. Darwinian theory really
is about the natural selection of traits in populations by virtue of
the superior fitness of the traits.
==== "inherited propensity for reproductive success" ====
(See other followup.) The difficulty with "inherited propensity for
reproductive success" is with establishing that there is such a thing
in any meaningful sense. Suppose, to be slightly more specific, you
have a species with two alleles A and a of a gene. At one particular
time you measure the prevalence of the two alleles and discover that
the populations are dominated by allele A and that, in the current
generation, those with allele A (prokaryotes for convenience) have a
better track record at reproducing. Does this tell you that allele A
has superior fitness? Alas, no. At a later time you may make the
same measurement and discover that allele a now appears to be
superior. How do you determine these propensities?
==== adaptation is a consequence of natural selection ====
* >So what proposition are you referring to here? Presumably you're
referring
* >to the proposition that natural selection occurs. But this
proposition is
* >not, in itself, an interesting or controversial one, so it's not
important
* >whether it's tautological or not.
No. I'm referring to the thesis that adaptation is a consequence of
natural selection. This is fundamental to evolutionary theory. It is
generally agreed (except possibly by Moran) that genetic drift does
not explain adaptation. You cannot defend this
==== Genetic drift explains adaptation says Moran others disagree ====
No. I'm referring to the thesis that adaptation is a consequence of
natural selection. This is fundamental to evolutionary theory. It is
generally agreed (except possibly by Moran) that genetic drift does
not explain adaptation. You cannot defend this thesis if you are
using a circular definition of natural selection.
=== post 23 ===
==== natural selection is some people having more kids than others
====
So, if some people are defining "natural selection" as merely the fact
that
some individuals have more offspring than others, without mentioning
that
the differential reproductive success is partly based on inheritance,
then I
think this is unfortunate, but not necessarily serious, as long as the
full
description of the theory of evolution mentions inheritance. In any
case,
this limited definition is not circular.
=== post 24 Hershey Howard ===
==== natural selection not synonymous with evolution ====
Although natural selection certainly plays a major evolutionary role,
it is not synonymous with evolution. You can
have natural selection without evolutionary impact and you can have
evolution (of the neutral kind) without natural selection. If that is
what you mean by "intrinsic fitness", I agree, but would prefer that
it be called the "heritable component of fitness". The "heritable
component of fitness" is important for evolution.
==== The idea of intrinsic fitness ====
OTOH, if by 'intrinsic fitness' you mean the idea that a phenotype has
an 'intrinsic' fitness value in the sense that that value or
directionality will adhere to the phenotype in any other environment,
I would disagree most strongly.
==== How is fitness determined ? ====
The concept described above as being 'intrinsic fitness' is precisely
the type of idea with which I disagree strongly. Fitness is
determined by the interaction of phenotype and environment.
It is not an intrinsic property of phenotype alone.
==== Howard disagrees with Richard Wein over the concept of fitness
====
* > It isn't possible to measure intrinsic fitness precisely.
Observed fitness
* > is only a statistical approximation to intrinsic fitness. But
that's no
* > reason why we can't define a concept of intrinsic fitness.
The concept described above as being 'intrinsic fitness' is precisely
the type of idea with which I disagree strongly. Fitness is
determined by the interaction of phenotype and environment. It is not
an intrinsic property of phenotype alone.
TAGS: [[RichardWein]] , [[RichardHarter]] , HersheyhPragmatics
==== Where does Natural Selection occur ? ====
> I think the theory of evolution is clear on this point. Organisms have a
> propensity for reproductive success which includes a hereditary element. Or,
> to put it another way, fitness is partly inherited.
Fitness is *often* partly inherited because phenotypes are *often*
partly a consequence of genotypes. Selection, however, is independent
of whether or not the phenotype is or is not a consequence of
genotype. But evolutionarily relevant fitness most certainly is not
independent of whether the phenotype is or is not a consequence of
genotype. Selection occurs at the phenotypic level and that is where
fitness is determined as well. The environment does not 'read'
genotypes; it does 'read' phenotypes.
==== Where is fitness determined ? ====
Fitness is *often* partly inherited because phenotypes are *often*
partly a consequence of genotypes. Selection, however, is independent
of whether or not the phenotype is or is not a consequence of
genotype. But evolutionarily relevant fitness most certainly is not
independent of whether the phenotype is or is not a consequence of
genotype. Selection occurs at the phenotypic level and that is where
fitness is determined as well. The environment does not 'read'
genotypes; it does 'read' phenotypes.
==== Genotypic variation created by natural selection ====
One way to generate phenotypic variation is via genotypic
variation (this is the only evolutionary relevant type of phenotypic
variation). The only way known by which genotypic variation is
generated in nature is through random mutation. That, of course, is
how natural selection is connected to evolutionary change over time.
But it does not mean that "natural selection" requires "random
mutation" to be included in its definition.
==== Natural selection can have both an evolutionary and non-
evolutionary consequence ====
I described what "natural selection" is. The term is not simply a
synonym for "evolution". One can have natural selection that has no
evolutionary consequences. One can also certainly have natural
selection that does have evolutionary consequences. Whether the
phenotypes have a genetic basis is what determines this. You can also
have evolutionary consequences in the absence of natural selection
(neutral drift, founder effects, etc.). Natural selection is a
mechanism that is not identical to evolution. It is one mechanism by
which evolutionary change can occur.
==== Do all phenotypes have a genetic basis ? ====
I described what "natural selection" is. The term is not simply a
synonym for "evolution". One can have natural selection that has no
evolutionary consequences. One can also certainly have natural
selection that does have evolutionary consequences. Whether the
phenotypes have a genetic basis is what determines this. You can also
have evolutionary consequences in the absence of natural selection
(neutral drift, founder effects, etc.). Natural selection is a
mechanism that is not identical to evolution. It is one mechanism by
which evolutionary change can occur.
=== post 25 Richard ===
==== Functional fitness fundamental element in Darwin's argument ====
Presumed functional fitness of traits (with heritability and
variation) is a fundamental element in Darwin's argument.
==== NetcomJump ====
[[NetcomJump]] , [[RichardHarter]]
Richard Wein wrote
> "Natural selection" cannot contain circular reasoning because it's an
> *expression*, not a *proposition*.
> The proposition "natural selection occurs" may contain circular reasoning
> (depending on how you define natural selection) but it's a straw man.
No, this is hopelessly confused. The term 'straw man' is applied to
*arguments* : "Natural selection occurs" is not an argument.
Futhermore 'circular reasoning ' occurs in an argument when
one of the premises is identical to the conclusion - but again
""Natural selection occurs" is not an argument.
=== Post 41 ===
==== Pattern design distinction ====
See [[RichardHarter]]
> Is there any explanation for HOW "natural selection"
> causes adaptive evolution, or does it just happen "by
> definition"?
I will repeat part of a reply to a post that I tried to e-mail to you,
but got returned.
Perhaps an analogy is in order. The environment's role in the
selection process is like that of a seive in the sorting process of
mixed gravel and sand (a mixture of size phenotypes, if you will). A
seive blindly sorts the mixture and you wind up with larger gravels
being largely retained and smaller gravels being largely lost by
passing through. Notice that there is a directionality to this
sorting process. It is the *larger* gravels that are retained by the
seive. To claim that it is the *smaller* gravels that get retained by
the seive would be to distort the common meaning of "larger" and
"smaller" so that they mean the opposite of what most people
understand. In the same way, the environment retains those organisms
best adapted to that sorting environment. Natural selection can no
more selectively retain the phenotypes maladapted to its environment
than a seive can selectively retain the smaller gravels. To retain
maladapted organisms, you have to have an intelligent designer
intervene to save them (as humans sometimes do in artificial
breeding). Retention of well-adapted organisms is not evidence for
intelligent design; selective retention of maladapted organisms is.
Friar Broccoli
You will note that Dr Wilkins is here:
http://groups.google.com/group/talk.origins/msg/78bb83b5946a1430
suggesting a classification system for tautologies. Hopefully
just what type of tautology fits in which category will be explored
in the coming days.
If things are as usual, we will find that the creationists are
making claims that cross definitional lines and thus muddling
distinct concepts, making claims for one that can only apply to
another. Right now, I don't have a clear idea.
>
> Some quotes from Henry Morris (Henry Morris, ed. 1985: Scientific
> Creationism, Master Books):
>
> "Creationists have long argued that natural selection has no
> predictive value and thus is a mere tautology, stating the obvious
> fact that organisms that "survive" are thereby decreed to have been
> the "fittest," but it reveals nothing whatever about how they evolved
> in the first place." page viii
>
> "Evolution is dogma incapable of refutation." page 6
>
> "A theory which incorporates everything really explains nothing! It
> is tautologous. Those who survive in the struggle for existence are
> the fittest because the fittest are the ones who survive." page 7
>
> Another quote from Ann Coulter (page 213 of her "Godless" book):
>
> "The beauty of having a scientific theory that's a tautology is that
> it can't be disproved. Evolution cultists denounce 'Creation Science'
> on the grounds that it's not 'science' because it can't be observed or
> empirically tested in a laboratory. Guess what else can't be observed
> or empirically tested? Evolution!"
These cites will be useful references, and help insure that we
are addressing the real claims made by creationists.
> I interpret these remarks to mean that they do not regard tautologies
> as inherently bad, but rather, that tautologies are bad because they
> can't be tested. Tautologies that are definitions are presumably OK.
>
> Arguably, the phrase "the survival of the fittest" is a tautology
> because it was really intended to be a definition of "fittest" or, at
> least, to suggest the definition of fitness.
>
> In any case, there is nothing in the phrase "the survival of the
> fittest" or in the definition of tautology that precludes Darwin or
> anyone else from particularizing fitness to a specific situation in
> which fitness is testable. In fact, that is what scientists are
> expected to do and do do.
Wilkins original FAQ suggested (in response to Popper's claim)
some areas that could be tested. One that I am particularly
struck by is "efficiency" which fundamentally means doing the
most with the least amount of resources. Even butterfly
mimicry fits very nicely into this model, as do quick turning
antelope (why run when you can just outmaneuver).
Efficiency is self-evidently a clear and major subcategory of
fitness and since it has a precise meaning is obviously distinct
from survival, although as you state below, it needs to be
further broken down into specific instances as do all general
scientific laws.
> Note that no scientific law or theory (or hypothesis, for that matter)
> can be tested as a general concept. Only specific instances can be
> tested. For example, you cannot test Newton's Law of Gravitation as
> an isolated concept. You can only test specific instances, e.g., when
> it is used to predict the orbit of Mercury in our solar system. See
> the Duhem-Quine thesis article in the Wikipedia for more information.
I think the comments by JJ Lodder and Steven L are bringing this
point out.
John S. Wilkins
> > We need to distinguish several things that get called tautologies:
> >
> > 1. Definitional tautologies; bachelors are unmarried males.
> >
> > 2. Logical tautologies: the RHS is formally implied by the LHS of the
> > equation
> >
> > 3. Mathematical tautologies: terms either side of an equals sign are
> > coterminous
>
> As a result of comments by Burkhard I stumbled across a
> circular reasoning "tautology":
>
> "Women write the best novels because men do not write novels as well."
>
> would this fit into the class of Logical tautologies?
Informally, yes. You'd need to recast it in formal logic.
Steven L.
It would be useful, thanks--
because Friar Broccoli's writeup, as written, implied that this
tautology argument is recent. In fact, it's one of the older arguments
against evolution (though the "watchmaker analogy" actually precedes
Darwin!).
How about a timeline for the talk.origins website, showing when each of
these arguments against evolution was first promulgated popularly?
Watchmaker analogy: William Paley, 1802
Tautology: Pierce et al., late 19th century
Geology: George McCready Price, circa 1920
Intelligent Design: Behe, Dembski, 1990s
John S. Wilkins
TomS
<LL2dnYN47O-2KxfX...@earthlink.com>, Steven L. stated..."
All of these go back much further.
Many of the creationist arguments can be found in Cicero.
How about naming the arguments which are the most recent?
"Irreducible complexity" - 17th century
"Second law of thermodynamics" - it can't be before the 19th century
"Darwin led to bad consequences" - in the sense of blaming Darwin
for German militarism goes back to shortly after 1914
--
---Tom S.
"...ID is not science ... because we simply do not know what it is saying."
Sahotra Sarkar, "The science question in intelligent design", Synthese,
DOI:10,1007/s11229-009-9540-x
Walter Bushell
<cfbee4d5-b9e6-478f...@v20g2000yqm.googlegroups.com>,
Friar Broccoli <eli...@gmail.com> wrote:
> As a result of comments by Burkhard I stumbled across a
> circular reasoning "tautology":
>
> "Women write the best novels because men do not write novels as well."
>
> would this fit into the class of Logical tautologies?
>
We would have to consider the class of castrati.
Walter Bushell
jo...@wilkins.id.au (John S. Wilkins) wrote:
For instance,
> the ideal gas law PV=nRT explains why temperature and pressure covary,
> although this is a simple tautology. When you interpret P as pressure,
> measured in a physical manner, V as volume, measured in a physical
> manner, and T as temperature, measured in a physical manner, n as the
> number of gas molecules, and R as the gas constant for each gas, you
> have an explanation.
Except no gas follows the idea gas laws. IOW no gas is ideal.
John S. Wilkins
Which is also part of the physical interpretation. At some point the
deviations are too great to ignore for practical purposes. But the law
does explain and predict, and it is a tautology.
J. J. Lodder
> On Aug 17, 5:14 am, nos...@de-ster.demon.nl (J. J. Lodder) wrote:
> > David Hare-Scott <sec...@nospam.com> wrote:
> > > I think I know what you are driving at but as it stands it's just a
> > > contradiction.
> >
> > The friar is not clear in his mind on the disticttion
> > between mathematical equations and physical ones.
> >
> > F = ma as an axiom in a mathematical formulation of Newton's theory
> > and F = ma as an economical description of thing observble
> > are entirely different things conceptually,
> > even though they look just the same.
> >
> > (I'll try to come back to this point)
>
> Yes, I would VERY much like more input on this point/issue.
> The distinction between physical reality and the formulations
> that people use to describe them is central to many of the points
> I am trying to make.
Short on time, but no lack of good intentions.....
Jan
J. J. Lodder
> Walter Bushell <pr...@panix.com> wrote:
>
> > In article <1j4mc6v.1nh8e1r1nopur1N%jo...@wilkins.id.au>,
> > jo...@wilkins.id.au (John S. Wilkins) wrote:
> >
> > For instance,
> > > the ideal gas law PV=nRT explains why temperature and pressure covary,
> > > although this is a simple tautology. When you interpret P as pressure,
> > > measured in a physical manner, V as volume, measured in a physical
> > > manner, and T as temperature, measured in a physical manner, n as the
> > > number of gas molecules, and R as the gas constant for each gas, you
> > > have an explanation.
> >
> > Except no gas follows the idea gas laws. IOW no gas is ideal.
>
> Which is also part of the physical interpretation. At some point the
> deviations are too great to ignore for practical purposes. But the law
> does explain and predict, and it is a tautology.
As a mathematical formula, yes.
As a physical law it is falsified by experiment,
Jan
Walter Bushell
But Newton's theory rises and falls upon its agreement with experience.
IOW, "F=ma" as an axiom is only important because the theory it is
embedded in matches experience validated by experiments and applications.
Walter Bushell
<606571a9-005a-4fb1...@z24g2000yqb.googlegroups.com>,
el cid <elcid...@gmail.com> wrote:
>
> It certainly is true that something like being faster than their
> fellows yields a competitive advantage for some gazelles. over
> others. In form the theory of natural selection is right. But it is
> so much more complicated that our simple notions of "fastest" being
> "fittest".
And what else the animal in question has to give up for the advantages
of speed. Parasite resistance could be one. It doesn't matter how fast
you are on a good day, if you are sick and having a slow day. _Parasite
Rex : Inside the Bizarre World of Nature's Most Dangerous Creatures_
give a good overview of this.
It sort of like those role playing games where you have a certain number
of points to distribute among various strengths of your character.
Steven L.
What underlies creationist attacks like tautology, watchmaker analogy,
and Omphalos, is a basic distrust of how empirical science works.
Particularly the principle of induction: If we do enough experiments to
confirm the acceleration of gravity is always the same in all
experiments, then we accept that as a law of nature. If we discover
that DNA carries the genetic code, and the evolution of genomes seems to
parallel the evolution of species postulated by earlier biologists going
back to Darwin, then that powerfully confirms the ToE. Or does it???
We just saw another such attack in this NG, by the poster Bill on
"Objective Anti-Intellectualism". In which he argued that we even can't
be sure of the reality in the external world (a problem going back at
least as far as Descartes).
This problem--Does induction work--perplexed philosophers for centuries.
David Hume and al-Ghazali believed that induction was logically
incorrect, and that the next experiment could conceivably produce a
different result than the last 10,000 experiments on the same thing.
The next time we sequence the genome of some species we hadn't done yet,
it *might* turn out to be so radically different from what was expected
by the ToE that it will overturn the ToE. But could that happen???
And sure enough, Karl Popper, who had attacked "Darwinism" as
untestable, had also attacked the philosophical validity of Bayesian
statistical inference, which can be taken as the mathematical
justification for experimental induction in science. (You can think of
doing hundreds of scientific experiments as "polling" a sample of the
Universe, much as Gallup polls a sample of people to estimate the
opinions of a population).
Well, Popper didn't believe that statistical inference is necessarily
philosophically admissible either (so much for those public opinion polls).
At some point, Talk.origins needs to say something about this basic
question: Is experimental induction philosophically valid? (If it's
not, then no amount of study of fossils, geological strata, or genomes
will ever be taken as sufficient proof of the ToE, by those who have the
philosophy that one-off miracles can occur anywhere at any time, should
God will it.)
Anyway, that's as far as my thinking takes me here.
J. J. Lodder
Indeed. One wouldn't bother to axiomatize a physical theory
unless it agrees with experiment very well.
Jan
John S. Wilkins
This certainly looks interesting.
I assume we are talking about more than the law breaking down
when the number of atoms becomes tiny, or so great that it is
described as meteorology?
Ernest Major
<jo...@wilkins.id.au> writes
>Posting this for the Good Friar Brocolli
>
>J. J. Lodder <nos...@de-ster.demon.nl> wrote:
>
>> John S. Wilkins <jo...@wilkins.id.au> wrote:
>>
>> > Walter Bushell <pr...@panix.com> wrote:
>> >
>> > > In article <1j4mc6v.1nh8e1r1nopur1N%jo...@wilkins.id.au>,
>> > > jo...@wilkins.id.au (John S. Wilkins) wrote:
>> > >
>> > > For instance,
>> > > > the ideal gas law PV=nRT explains why temperature and pressure covary,
>> > > > although this is a simple tautology. When you interpret P as pressure,
>> > > > measured in a physical manner, V as volume, measured in a physical
>> > > > manner, and T as temperature, measured in a physical manner, n as the
>> > > > number of gas molecules, and R as the gas constant for each gas, you
>> > > > have an explanation.
Here n is the number of moles, not molecules. The alternative
formulation is PV=NkT, where N is the number of molecules and k is
Boltzmann's constant.
>> > >
>> > > Except no gas follows the idea gas laws. IOW no gas is ideal.
>> >
>> > Which is also part of the physical interpretation. At some point the
>> > deviations are too great to ignore for practical purposes. But the law
>> > does explain and predict, and it is a tautology.
>>
>> As a mathematical formula, yes.
>> As a physical law it is falsified by experiment,
>>
>
>This certainly looks interesting.
>
>I assume we are talking about more than the law breaking down
>when the number of atoms becomes tiny, or so great that it is
>described as meteorology?
>
Yes. The Ideal Gas Law breaks down in conditions nearer to common
experience. (WikiPedia says that it works best for monatomic gases at
high temperatures and low presssures.)
An ideal gas is "composed of a set of randomly-moving point particles
that interact only through elastic collisions" (WikiPedia). As gas
molecules have a finite volume the Ideal Gas Law breaks down at high
densities. It breaks down at low temperatures (it fails to predict
condensation) when gas molecules can stick together because of
intermolecular forces. I'd have to hit the text books to check whether
the excitation of stretching and bending modes of polyatomic gas
molecules also causes deviations.
--
alias Ernest Major
Steven L.
The basic assumption behind the Ideal Gas Law is that interactions
between molecules are elastic collisions--momentum and energy are
conserved. But as you describe, when temperatures are low enough,
collisions between molecules turn inelastic; energy is stored in the
intermolecular forces, causing the molecules to "stick together".
J. J. Lodder
No, as long as equipartition holds.
(That is, in the classical regime)
The internal degrees of freedom
show up only in the specific heats,
Jan
ivar
On Aug 17, 8:22 pm, Friar Broccoli <elia...@gmail.com> wrote:
> On Aug 17, 9:09 am, Burkhard <b.scha...@ed.ac.uk> wrote:
>
> > On Aug 16, 11:45 pm, Friar Broccoli <elia...@gmail.com> wrote:
>
> > Rather, "survival of
>
> > > the fittest" is more like an advertising slogan or label,
> > > focusing attention on a key idea in the natural selection
> > > process.
>
> > I would probably avoid the expression "advertising slogan" -
> > advertising is too close to propaganda, which is too close to "not
> > being quite truthful"
>
> Yes, "label" is probably better.
I've been searching for a term that better conveys the role of the
phrase "the survival of the fittest." It seems that the English
language should have one. "Label" is probably OK but seems a bit dull
and forgettable. What about "evocative label"? Other terms that have
been mentioned are catchphrase, epigram, and bumper-sticker.
> > > - repetition of meaning, using different and dissimilar words or
> > > symbols to effectively say the same thing twice.
>
> > I would drop this. It covers too many stylistic sins that have nothing
> > to do with tautologies. We can always make a logically valid argument
> > longer by unnecessarily repeating some premises. Pleonasm is another
> > example. Wikipedia claims that these are called tautologies by the
> > rhetorical tradition, but does not give a cite, and I don't can't
> > remember ever seen this expression used by the major writers on
> > rhetoric. Barring some good evidence that these stylistic
> > transgressions have historically been grouped together with
> > fallacious arguments, I would leave them out.
>
> I am inclined to go the other way and suggest many definitions
> because:
>
> 1- people are unlikely to agree with any definition we try to
> enforce.
> 2- By suggesting several different definitions the boundary
> lines between the definitions and thus their meaning will
> become clearer to the reader, who's understanding of what a
> tautology is will almost always be hazy.
> 3- In almost all arguments, creationists (I believe
> unintentionally) move from one meaning of a word to another.
> A reader who is aware of two or more possible meanings of
> tautology will find it easier to spot such moves.
The Oxford English Dictionary states that "The repetition (esp. in the
immediate context) of the same word or phrase, or of the same idea or
statement in other words" has been a definition of "tautology" since
the 1500's. This definition is much older than the definition now
used in logic. The OED defines the latter as "A compound proposition
which is unconditionally true for all the truth-possibilities of its
elementary propositions and by virtue of its logical form."
However, it is the latter definition which is relevant here. It may
be useful to mention the former definition because some people will be
aware of it or will look up "tautology" in the Wikipedia. Then, you
could say the definition is not relevant here.
Ivar
ivar
> Darwinian theory rules out
> quite a lot.... It rules out new
> species being established without ancestral species.
>
> All of these hypotheses are more or less testable, and conform
> to the standards of science.
I'll quibble with this wording (which is from the original tautology
FAQ).
How does one test this statement: "[Darwinian theory] rules out new
species being established without ancestral species"? Darwinian
theory predicts that species have ancestral species and this is
testable. But that does not rule out the possibility that there might
be exceptions. Suppose the theists (like Darwin's wife) are right and
there is a Creator. And suppose this Creator from time to time
creates a new species for His own amusement. What tests can a
Darwinist run to verify this never happens? It's the white swan
problem. Proving that something has never happened or never can
happen is very difficult in science. And, remember that the contents
of this FAQ page are ultimately intended mainly for readers who firmly
believe in a God that can perform miracles.
Ivar
John S. Wilkins
> I'm trying the cc trick.
>
> On Aug 17, 8:22 pm, Friar Broccoli <elia...@gmail.com> wrote:
> > On Aug 17, 9:09 am, Burkhard <b.scha...@ed.ac.uk> wrote:
> >
> > > On Aug 16, 11:45 pm, Friar Broccoli <elia...@gmail.com> wrote:
> >
> > > Rather, "survival of
> >
> > > > the fittest" is more like an advertising slogan or label,
> > > > focusing attention on a key idea in the natural selection
> > > > process.
> >
> > > I would probably avoid the expression "advertising slogan" -
> > > advertising is too close to propaganda, which is too close to "not
> > > being quite truthful"
> >
> > Yes, "label" is probably better.
>
> I've been searching for a term that better conveys the role of the
> phrase "the survival of the fittest." It seems that the English
> language should have one. "Label" is probably OK but seems a bit dull
> and forgettable. What about "evocative label"? Other terms that have
> been mentioned are catchphrase, epigram, and bumper-sticker.
Drop the "advertising" - it's a slogan, pure and simple. Used for
rallying the troops and teaching to undergraduates (which amounts to
pretty much the same thing).
The term has a particular meaning in the philosophy of science, and it
is worth distinguishing the semantic from the logical here. The core of
the criticism against natural selection is that it is a *logical*
tautology, which amounts to it being an a priori truth (which most
philosophers now deny exist, anyway).
In logic, a tautology is, and I quote:
"A sentence \phi is _tautologous_ (or it is a _tautology_) if and only
if it is assigned a truth-value T by every normal assignment of
truth-values T and F to the sentences of \Fraktur_L.
Further, a sentence \phi is a _tautological consequence_ of a set of
sentences \GAMMA if and only if \phi is assigned the truth-value T by
every normal assignment that assigns the truth-value T to all sentences
of \GAMMA."
Benson Mates, _Elementary Logic_, second edition, page 89.
Shorn of the logic-speak, it basically means that a sentence (not a
phrase like "survival of the fittest" is a tautology if it is always
true in some formal language, and it is a tautologous consequence if it
always gets assigned "true" in some set of sentences.
For our purpose, this would mean that the theory of Darwinian evolution
by natural selection - call it NS - has "survival of the fittest defines
fitness" as true no matter what else the theory NS says, under every
interpretation, and, as Gould points out in his "Darwin's Untimely
Burial" essay, this simply isn't the case. There are organisms with
traits that are clearly not fit, and we can debate on empirical grounds
whether traits are fit or not and why.
ivar
> For our purpose, this would mean that the theory of Darwinian evolution
> by natural selection - call it NS - has "survival of the fittest defines
> fitness" as true no matter what else the theory NS says, under every
> interpretation, and, as Gould points out in his "Darwin's Untimely
> Burial" essay, this simply isn't the case. There are organisms with
> traits that are clearly not fit, and we can debate on empirical grounds
> whether traits are fit or not and why.
I'll suggest a somewhat different approach. Accept "the survival of
the fittest" as a tautology on the basis that it is a definition of
fitness. (It can be rewritten as sentence.) Then, ask whether it is
possible to test particular traits in particular organisms, e.g.,
running speed in rabbits, to see if the trait increases the
probability of survival. If the answer is yes (and, obviously, one
can often devise suitable tests), then one can determine whether the
trait does or does not contribute to an organism's fitness. Hence,
natural selection is testable and not a tautology.
Some issues need to be clarified. For example, how does one assess
the probability of survival?
[ Hence, W_abs_ = N_after_/N_before_ , etc. ]
Note that it is possible that an hypothesis about which traits enhance
survival could be wrong. The important thing in this debate is that
hypotheses be testable, not that they be true. Of course, testing
must confirm that some traits do enhance survival.
Note also that testing whether a trait aids survival in nature can be
difficult. The survival of an organism depends on many factors, only
one of which is the trait being tested. The fast rabbit could be hit
by lightning. Hence, the scientist must use statistical techniques
like those used in medical research to determine whether a trait is
really important.
Ivar
el cid
> On Aug 20, 9:22 pm, j...@wilkins.id.au (John S. Wilkins) wrote:
>
> > For our purpose, this would mean that the theory of Darwinian evolution
> > by natural selection - call it NS - has "survival of the fittest defines
> > fitness" as true no matter what else the theory NS says, under every
> > interpretation, and, as Gould points out in his "Darwin's Untimely
> > Burial" essay, this simply isn't the case. There are organisms with
> > traits that are clearly not fit, and we can debate on empirical grounds
> > whether traits are fit or not and why.
You are changing the meaning of fit. If SoF is a tautology,
and it is, fit or fitness has a technical definition. You
don't debate it, you measure it.
> I'll suggest a somewhat different approach. Accept "the survival of
> the fittest" as a tautology on the basis that it is a definition of
> fitness. (It can be rewritten as sentence.) Then, ask whether it is
> possible to test particular traits in particular organisms, e.g.,
> running speed in rabbits, to see if the trait increases the
> probability of survival. If the answer is yes (and, obviously, one
> can often devise suitable tests), then one can determine whether the
> trait does or does not contribute to an organism's fitness. Hence,
> natural selection is testable and not a tautology.
SoF is a tautology, not NS. Full Stop.
What's the problem?
> Some issues need to be clarified. For example, how does one assess
> the probability of survival?
>
> [ Hence, W_abs_ = N_after_/N_before_ , etc. ]
>
> Note that it is possible that an hypothesis about which traits enhance
> survival could be wrong. The important thing in this debate is that
> hypotheses be testable, not that they be true. Of course, testing
> must confirm that some traits do enhance survival.
What's your point? A trait may increase fitness, decrease fitness
or be neutral (1). This has nothing to do with SoF being a tautology.
It has nothing to do with NS not being a tautology.
> Note also that testing whether a trait aids survival in nature can be
> difficult. The survival of an organism depends on many factors, only
> one of which is the trait being tested. The fast rabbit could be hit
> by lightning. Hence, the scientist must use statistical techniques
> like those used in medical research to determine whether a trait is
> really important.
Measurements have error. This is an important point but how
does it address issues of tautology?
Why not keep it simple?
tg
Friar Broccoli
ivar
> On Aug 21, 7:27 am, ivar <ylvis...@verizon.net> wrote:
> > I'll suggest a somewhat different approach. Accept "the survival of
> > the fittest" as a tautology on the basis that it is a definition of
> > fitness. (It can be rewritten as sentence.) Then, ask whether it is
> > possible to test particular traits in particular organisms, e.g.,
> > running speed in rabbits, to see if the trait increases the
> > probability of survival. If the answer is yes (and, obviously, one
> > can often devise suitable tests), then one can determine whether the
> > trait does or does not contribute to an organism's fitness. Hence,
> > natural selection is testable and not a tautology.
>
> SoF is a tautology, not NS. Full Stop.
> What's the problem?
Creationists like Henry Morris and Ann Coulter argue that SoF and NS
are names for the same process and they can point to Darwin's words in
the 5th edition "Of the Origin of Species" for support. Hence, if SoF
is a tautology, then NS must be also. To respond to this claim, one
must distinguish between SoF as a definition of fitness and SoF as an
alternative label for NS.
> > Note that it is possible that an hypothesis about which traits enhance
> > survival could be wrong. The important thing in this debate is that
> > hypotheses be testable, not that they be true. Of course, testing
> > must confirm that some traits do enhance survival.
>
> What's your point? A trait may increase fitness, decrease fitness
> or be neutral (1). This has nothing to do with SoF being a tautology.
> It has nothing to do with NS not being a tautology.
I had in mind that the case for NS might be weakened if the defense is
based on claims that organisms with certain traits are fit as opposed
to claims that certain traits can be tested. A creationist could
insinuate that NS is worthless because the rationale for NS relies on
claims that are unproven.
> > Note also that testing whether a trait aids survival in nature can be
> > difficult. The survival of an organism depends on many factors, only
> > one of which is the trait being tested. The fast rabbit could be hit
> > by lightning. Hence, the scientist must use statistical techniques
> > like those used in medical research to determine whether a trait is
> > really important.
>
> Measurements have error. This is an important point but how
> does it address issues of tautology?
>
> Why not keep it simple?
Creationists claim that NS is untestable. I am concerned that a
defender of NS might get into trouble when he or she tries to answer
this claim if they don't realize that testing NS can be difficult.
After all, how does one demonstrate that faster rabbits are fitter?
How many rabbits does one need to test and for how many generations?
You have to keep track of which rabbits are offspring of which rabbits
and that's not so easy if the rabbits are wild rabbits. How do you
measure the speed of a rabbit? And, how do you make sure that you are
measuring the consequences of running speed and not, say, the effect
of a virus that might be present in the rabbits that are being
studied? A creationist could argue that, even if NS is testable in
principle, it is impossible in practice.
Ivar
el cid
> On Aug 21, 8:29 am, el cid <elcidbi...@gmail.com> wrote:
>
> > On Aug 21, 7:27 am, ivar <ylvis...@verizon.net> wrote:
> > > I'll suggest a somewhat different approach. Accept "the survival of
> > > the fittest" as a tautology on the basis that it is a definition of
> > > fitness. (It can be rewritten as sentence.) Then, ask whether it is
> > > possible to test particular traits in particular organisms, e.g.,
> > > running speed in rabbits, to see if the trait increases the
> > > probability of survival. If the answer is yes (and, obviously, one
> > > can often devise suitable tests), then one can determine whether the
> > > trait does or does not contribute to an organism's fitness. Hence,
> > > natural selection is testable and not a tautology.
>
> > SoF is a tautology, not NS. Full Stop.
> > What's the problem?
>
> Creationists like Henry Morris and Ann Coulter argue that SoF and NS
> are names for the same process and they can point to Darwin's words in
> the 5th edition "Of the Origin of Species" for support. Hence, if SoF
> is a tautology, then NS must be also. To respond to this claim, one
> must distinguish between SoF as a definition of fitness and SoF as an
> alternative label for NS.
I do believe I've noticed this. It has featured prominently
in the alternatives I've presented. You define your terms
and keep defining them, pointing out where the intentional
or unintentional bait and switch happens for SoF definitions.
The problem is the illusion created by changing the underlying
concept that SoF refers to. That's 50% of the answer right there.
Just stay on message.
> > > Note that it is possible that an hypothesis about which traits enhance
> > > survival could be wrong. The important thing in this debate is that
> > > hypotheses be testable, not that they be true. Of course, testing
> > > must confirm that some traits do enhance survival.
> > What's your point? A trait may increase fitness, decrease fitness
> > or be neutral (1). This has nothing to do with SoF being a tautology.
> > It has nothing to do with NS not being a tautology.
> I had in mind that the case for NS might be weakened if the defense is
> based on claims that organisms with certain traits are fit as opposed
> to claims that certain traits can be tested. A creationist could
> insinuate that NS is worthless because the rationale for NS relies on
> claims that are unproven.
The case is what it is. Just be very very clear about it.
Don't try to combat rhetorical sleight of hand with more of
the same.
This the the tautology FAQ. SoF in the narrow sense defines
fitness. The one sentence definition of fitness is a tautology.
The one sentence definition of fitness is not the same thing
as Natural Selection, it's a piece of it. Natural selection
is not a tautology in the same sense as SoF is. Natural
selection is a logical argument about what happens over
multiple generations. It's been observed. Fitness can be
greater than 1 or less than 1. Natural selection for both
cases has been observed. No problems. It ain't broke,
don't fix it.
> > > Note also that testing whether a trait aids survival in nature can be
> > > difficult. The survival of an organism depends on many factors, only
> > > one of which is the trait being tested. The fast rabbit could be hit
> > > by lightning. Hence, the scientist must use statistical techniques
> > > like those used in medical research to determine whether a trait is
> > > really important.
>
> > Measurements have error. This is an important point but how
> > does it address issues of tautology?
>
> > Why not keep it simple?
>
> Creationists claim that NS is untestable.
It's observable. Cite observations.
> I am concerned that a
> defender of NS might get into trouble when he or she tries to answer
> this claim if they don't realize that testing NS can be difficult.
> After all, how does one demonstrate that faster rabbits are fitter?
Cliches about faster animals being fitter are bad examples.
They lead to a false sense of understanding.
Now that J. Wilkins book on species is out, he ought to write
the next one on "fitness". Prior to that,
Let's recall the mighty words of Stern, "Fitness, something
everybody understands but no one can define precisely".
Life-history tactics: a review of the ideas Q. Rev. Biol., 51:3-47
http://www.yale.edu/eeb/stearns/pdf/01.Stearns1976QRB.pdf
Or one could contemplate
"The fitness of fitness concepts and the description of
natural selection" DeJong Q. rev. Biol, 69:3-29
http://www.ugr.es/~jmgreyes/DeJong.pdf
and if you are a glutton,
http://www.yale.edu/eeb/stearns/publications.htm#pdfs
The point that emerges, and some already know, is that
our formulation of natural selection is naively
over-simplified. This is especially true once complex
equilibria have been established, and if your
species has survived long enough in roughly the
same selective environment, such quasi-equilibria
probably have established. This means the magnitude
of the complicating 2nd and 3rd order terms have
become significant.
Do you possibly think you can go into these ideas
in a FAQ? I don't think so.
The tautology issue is a simple game of multiple
meanings for a few terms: fitness, survival of
the fittest, natural selection and evolution.
Define these terms. Point out where sloppy usage
causes confusion. Show where the tautology can
exist. Show why it is not a problem. Stop.