A brief look at two comments on one
ID-creationist
website
By Mark Perakh
Posted on September 15, 2005
Although I avoid opening any
ID sites, from time to time I receive emails quoting certain
comments posted to such sites. The other day I received one
such email from Alan Fox. In his email Alan quoted three
comments that appeared on one of Dembski's sites and relate
to my essay (critical of Dembski), which was printed in the
Skeptic magazine, v. 11, No 4, 2005. (Its full text
is available online at
http://www.talkreason.org/articles/Skeptic_paper.cfm.)
So I unwillingly found myself looking at three hostile
comments regarding certain points in my Skeptic
essay. I shall quote here two of these comments as they
appeared in Alan's email.
One of these hostile comments
was by Salvador Cordova. In his frequent comments on Panda's
Thumb (PT) Salvador tries (not fully successfully) to
restrain his apparent penchant for exaggerating his
qualifications and denigrating the objects of his assaults.
In his comment on Dembski's site -- where he is protected by
the absence of counter-arguments -- he indulges in wild
attacks on Dembski's critics, including me. His comment is
full of repeated claims that I "mangled," "fumbled," and
"misrepresented" Dembski's great ideas and attacked straw
men.
Assertions that his critics
simply "do not understand" his concepts has been a device
often used by Dembski -- see for example his "replies" to
the critique by Ellery Eels, Robert Pennock, Richard Wein,
Erik Tellgren, Eli Chiprout, Wesley Elsberry, Jeffrey
Shallit, and others. I seem to be in good company. Can it be
that such a regularly employed accusation rather reflects
Dembski's (and even more so of Cordova's) inability to offer
more substantive counter-arguments?
Perhaps Salvador is sincere in
his desperate attempts to find errors in the critique of
Dembski. It is interesting, though, that, while Dembski
lets Salvador jump high in the "defense" of his "Lord
William," (which is how Cordova referred to Dembski on PT)
Dembski himself has so far never explicitly endorsed
Salvador's rants. Perhaps Dembski realizes the abysmal level
of Salvador's contentions and avoids being directly
associated with them.
Salvador's comment essentially
repeats his earlier assertions on PT, which have been
answered extensively in many other posts on PT. Therefore I
will not take space here for one more demonstration of
Salvador's fallacies; they have already taken too much space
on PT. Perhaps one brief comment may be in order. Replying
to my earlier comment on PT, where I wrote that I'd not
curtail Salvador's freedom to post anything he wants in my
threads, Salvador wrote that he respected me for that. If
so, then, to be consistent, should he not disrespect
Dembski, who deletes from his sites any comments he
dislikes?
I'll briefly discuss now the
other two comments copied from Dembski's site by Alan. Both
relate to just one point in my Skeptic essay, namely
one example of a false positive produced by Dembski's
explanatory filter (EF). This example refers to a rare form
of snowflakes, which appears under certain weather
conditions. Since the weather conditions in question are
very rare, the appearance of such snowflakes has a low
probability. These snowflakes also have a specific, easily
recognizable form that is the simplest kind of snowflakes
ever observed. Since in this case we have a combination of
low probability with specification, the inference prescribed
by Dembski's EF is that the snowflakes in question are
results of design -- it is just one more case of a false
positive.
Furthermore, according to
Dembski, low probability is just another face of complexity:
the more complex the object, asserts Dembski, the lower its
probability (in my Skeptic essay there are a number
of direct pertinent quotations from Dembski). In fact,
however, the rare snowflakes in question have the simplest
structure of all known snowflakes (see the relevant
references in my Skeptic essay). This exemplifies
the fallacy of Dembski's thesis, which equates complexity
with low probability.
Both hostile commenters hide
their names, one using a pseudonym ("taciturnus") and the
other just a first name ("dave"). What are these critics of
my essay afraid of? Do they know that their arguments are
false? Or are they just not sure their comments make sense?
Or do they hide their names so they can hurl insults with
impunity?
Let us see if their specific
critical remarks regarding the rare snowflakes have any
merits.
To avoid accusations of
distorting what my opponents say (if it is at all possible,
given the predilection of some of Dembski's supporters for
slandering his opponents), I'll reproduce here the full
texts of the hostile comments as quoted by Alan.
Here is the first of these
comments:
After addressing Alan, the
comment continues as follows:
1. "I've read your link to
Mark Perakh (Dream_Dem), and I now see what the ID defenders
mean when they imply that Mr. Perakh seems to go out of his
way to misunderstand Intelligent Design. Consider some of
his remarks about specified complexity:
'I believe that the very
concept of complexity as disguised improbability is contrary
to facts and logic. For example, under certain (rare)
weather conditions, an unusual triangular shape of
snowflakes can be observed.26 Unlike more common
forms of snowflakes with their intricately complex
structure, these rare snowflakes have a simple structure. As
Dembski asserted,27 snow crystals' shapes are due
to necessity -- the laws of physics predetermine their
appearance. However, triangular snowflakes, while indeed
predetermined by laws of physics, occur only under certain
weather conditions, which are very rare and unpredictable.
Therefore we have to conclude that the emergence of the
triangular snowflakes is a random event. This is another
example where at least two causal antecedents -- chance and
law -- are in play simultaneously.
'Since the appropriate weather
conditions occur very rarely, the probability of the chance
emergence of the triangular snowflakes is very small; also,
they have a uniquely specific shape. Hence, according to the
EF, these snowflakes were deliberately designed.'
"But complexity as
improbability is obviously meant as conditional
improbability. Given conditions A, the probability that B
will occur is so low that we can infer design. Given
whatever unusual whether conditions you prefer, the
probability that wind and rain will carve the faces of
Presidents on Mt. Rushmore is tiny. We can infer design.
However, given the right weather conditions, the probability
that triangular snowflakes will occur is high. We cannot
infer design, especially since the only time we see these
snowflakes is during the unusual weather conditions that
make them highly probable. This does not seem a difficult
point.
"Comment by taciturnus --
September 9, 2005 @ 7:31 am"
To start with, the example of
Mt. Rushmore is irrelevant. The Rushmore pattern has a human
origin and in such cases design inference is a well
established procedure based on our familiarity with human
design and its results. This procedure has nothing to do
with Dembski's EF (which anyway is, in my view, as evinced
in my Skeptic essay, a meaningless schema). In the case of
snowflakes no background knowledge of the kind we have with
a human design is available. This point has been thoroughly
discussed in literature (see, for example, the collection
Why Intelligent Design Fails, edited by Young and Edis,
now in its third printing with a paperback edition
forthcoming, where this point has been discussed in detail).
Look now at taciturnus's
argument which asserts that "complexity as improbability is
obviously meant as conditional improbability." Unfortunately
for taciturnus, it is not only not "obvious" that Dembski's
schema indeed implies conditional probability, but in fact
this schema does nothing of the sort, either obviously or
implicitly. Taciturnus seems to mix up two different
questions. One question is whether or not the snowflake in
question was designed? The other question is what inference
follows for Dembski's schema? If we were searching for the
answer to the first question, taciturnus's notion would be
reasonable: it is indeed obvious that in the case in point
there is no reason to infer design; the appearance of the
triangular snowflakes is predetermined by the combination of
proper weather conditions and laws of physics. This correct
inference is, though, done outside Dembski's EF. The answer
to the second question is that EF requires inferring design,
which is a false positive. Indeed, nowhere does Dembski's
schema imply the use of conditional probability.
If we turn to Dembski's actual
writing, we find that he pays a lot of lip service to
evaluating multiple "relevant chance hypotheses," although
he never himself bothers to go beyond evaluating a single
chance hypothesis that uses the uniform distribution.
Dembski's schema prescribes evaluation of probability,
period. In the case of snowflakes, the overall probability
comprises two components, one random, and the other
non-random. The random component is the (low) probability of
proper weather condition. The non-random component is the
(high) probability of laws of physics producing the
snowflakes in question under the proper weather condition.
Obviously the random component precedes the non-random one
in the causal chain. "Taciturnus" suggest to ignore the
random component and to base the inference only on the
non-random one. Such an approach would be contrary to
Dembski's schema.
Indeed, why should we base our
application of EF on the conditional probability of
the appearance of this type of snowflakes under given
weather condition (which is high) when it is obvious
that in the causal chain the probability of the proper
weather precedes the probability of "physical laws
producing such snowflakes"? Following Dembski's schema, we
cannot ignore the probability that is "upstream" in the
causal chain, as taciturnus suggests doing. The low value of
the probability that is "upstream" overrides the larger
probability that is "downstream."
Taciturnus's correct judgment
(that snowflakes in question are not designed) is based on
common sense and available background knowledge, but the
question is not about that. It is whether or not Dembski's
approach yields the correct conclusion. It does not, in part
because it does not prescribe using conditional probability
-- its use is just taciturnus's common sense suggestion
rather than a feature of Dembski's thesis.
From another angle, the
probability of the rare snowflakes being conditional on
weather, again, does not negate the fact that these
snowflakes have a low overall probability. Therefore
Dembski's formal thesis, if applied consistently, requires
the snowflakes to be complex. But they are simple.
Taciturnus's argument can in fact be used to argue against
EF and against Dembski's thesis of complexity being
equivalent to low probability.
Unfortunately for "taciturnus"
his (her) argument fails to properly address the question at
hand -- the validity of my example of the rare snowflakes.
Here is the second hostile
comment, as quoted by Alan:
2. "The snowflake example also
fails because the triangular design isn't specified
beforehand. This is just another version of the arrow and
the barn example. All points on the barn are equally
unlikely to be hit. A particular point on the barn is only
interesting if it has been specified before the event -- for
instance by a bullseye. (sic).
"The triangular snowflake is
no more interesting than a four-leaf clover, ball lightning,
or the aurora borealis. All are rare, complex natural
events, but none of them are specified before the event.
Their patterns are reducible to being a function of the
natural conditions that produced them, rare or otherwise.
All of them are surprising and remarkable, but from them no
reasonble person could ever infer design.
"The idea of specificity is so
fundamental to design inferences, it's astonishing that
Perakh considers this example applicable. Bill has asked if
Perakh understands the relevant math. After reading this,
I'm wondering if Perakh understands the relevant English.
"If Bill or any other ID
proponent had to correct every published essay that
exhibited a basic misunderstanding of the argument, they'd
spend all their time chasing down op-eds and blog blather. "
Comment by dave -- September
9, 2005 @ 1:33 pm"
I will not respond to dave's
remarks about my misunderstanding "relevant English," which
parrots Dembski's earlier infamous utterance -- such
derogatory remarks usually are offered when no arguments of
substance are available. Let us instead look at his argument
regarding the snowflake's shape not being specified
"beforehand," which, according to "dave," shows my lack of
understanding of the concept of specification.
Before discussing dave's
specific notions, it is perhaps proper to point out that
Dembski's concept of specification has been severely
critiqued by various reviewers. I have made some modest
(although rather detailed) contribution to the discussion of
Dembski's specification in my book Unintelligent Design
(Prometheus Books, 2004, pp. 47-53). In my Skeptic
essay I also have analyzed that concept but dave chose not
to notice that analysis. In an excellent article (which is
available online at
http://www.talkreason.org/articles/eandsdembski.pdf)
Elsberry and Shallit made mincemeat of Dembski's
specification concept. (As could be expected, apparently
incapable of providing a cogent response to Elsberry &
Shallit's article, Dembski's camp responded with hysterical
assaults like those by Salvador Cordova, who posted a number
of meaningless pieces of "critique" baselessly accusing
Elsberry and Shallit of [of course!] "misrepresenting"
Dembski's specification concept.)
Regarding dave's specific
argument (that specification must be made "beforehand"),
dave may be surprised to learn that it is contrary to
Dembski's thesis. Dembski unequivocally asserts (see
Dembski's The Design Inference, page 14) that the
pattern meeting the requirement of specification can be
legitimately identified after the fact. Dembski's
criterion for distinguishing between "specification" and
"fabrication" is not when the pattern was identified,
but whether or not it meets what Dembski calls
"detachability." This term, explains Dembski, means that the
pattern is "independent of an event."
(It can be noted that if the
requirement for the specification to be determined
"beforehand" were adopted, it would make the entire "design
inference" a la Dembski not applicable to biology. We
never know "beforehand" which pattern will have, say, a
hitherto unobserved chunk of DNA, or, say, how a hitherto
unknown species of bacteria will look like. That is why
Dembski prescribes testing for "detachability" rather than
for when the specification is made).
If dave's comment, as he
formulated it, were correct, it would first apply to Dembski
himself.
Recall Dembski's example
illustrating his concept of specification. (See, for
example, again Dembski's The Design Inference, where
the "detachability" is discussed in many words). A pattern
may serve as a specification, says Dembski, only if it is
"detachable." Let us see if the rare snowflakes meet this
condition.
In Dembski's own example, he
talks about a heap of stones which happens to reproduce the
shape of a constellation (this example is on page 17 of
Dembski's The Design Inference). When a layman sees
these stones he does not recognize the shape of a
constellation so the observed shape is not "detachable" and
does not serve as a specification. If, though, an astronomer
sees the same heap of stones, he recognizes the image of a
constellation (which he has previously stored in his mind
independently of the particular heap of stones he came
across) and in this case the observed pattern is
"detachable" and serves as specification.
The astronomer infers that
some intelligent agent has, by design, arranged the stones
in the shape of a constellation. He came to such a
conclusion because the shape of that constellation was
antecedently familiar to him. The astronomer did not expect
"beforehand" to find these particular stones arranged as
this specific constellation. However, the pattern he
observed was "detachable" as it matched an image he had,
antecedently and independently from this particular heap of
stones, stored in his mind. Recall that all this is
Dembski's own example illustrating his concepts of
"detachability" and "specification." This is the essence of
the notion that specification is predicated on prior
knowledge of the pattern -- which is a point rather
different from that made by dave. Dave avoided mentioning
"detachability," which would be a proper reference to
Dembski's thesis.
Exactly the same argument
applies to the snowflakes in question. For dave the shape of
the rare snowflakes is not familiar and therefore not
"detachable." Hence, for dave these snowflakes are not
"specified." However, to an expert on snowflakes the shape
is well known, so when such an expert sees those rare
snowflakes, he recognizes them as conforming to the image he
has antecedently kept in his mind. The pattern is, in this
case, according to Dembski's thesis, "detachable," exactly
as the pattern of the heap of stones in Dembski's own
example. Dembski's "theory" requires inferring design
equally in the case of stones and in the case of snowflakes.
This inference may be true for the heap of stones but
is false for the triangular snowflakes, and this shows the
inadequacy of Dembski's thesis.
When dave correctly concludes
that the rare snowflake is not a product of design, he (like
taciturnus) does so outside of Dembski's EF, and in fact his
conclusion is contrary to what EF yields. EF yields a false
positive.
Dave's comment shows his own
misunderstanding of the subject he decided to argue about.
The fact that neither hostile
commenter identified in my essay any more targets for their
(fallacious) critique, besides the sole example of the rare
snowflakes, is telltale. It points to their apparently being
at a loss when confronted with the entirety of my arguments.
Perhaps this is also the reason that, absent any more
visible targets for assaults, both commenters resorted to
general assertions regarding my "misunderstanding" of ID and
of Dembski's work.
If the comments by "taciturnus"
and "dave" plus the rants of Cordova are the best the ID
advocates can offer in response to my essay in the
Skeptic, their case has to be relegated to the dustbin
of history, to borrow Dembski's favorite pompous expression.
I believe unbiased readers can
themselves now infer who in this debate indeed poorly
understands Dembski's thesis, "relevant English" and the
super-sophisticated collections of math symbols so loved by
Dembski but evidently beyond the comprehension of some of
his supporters.
I thank Wesley Elsberry and
Matt Young for taking time to read the initial draft of this
piece and suggesting pithy comments.
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