From: Brian D Harper <bharper@postbox.acs.ohio-state.edu>
>At 10:48 AM 8/26/00 +0100, Richard wrote:
>
>[...]
>
>
>>According to the theory of evolution, evolution is a random process,
because
>>it involves random events: mutations are one type of random event; another
>>is the natural vicissitudes of life which determine which individuals
>>succeed in reproducing.
>>
>>Sure, this random process produces certain patterns, such as the trend
>>towards greater adaptation of a species to its environment. But it's still
a
>>random process.
>>
>>Similarly, an application of the Monte Carlo method is a random process,
>>even though it converges on a predictable result.
>
>Once again, I'm intrigued by your response.
I'm glad to hear that. ;-)
>It is common to hear creationists
>criticize evolution as a random process, but I have seen uniformly and
without
>exception (until now :) evolutionists emphasizing the point that evolution
>is not
>random even though it involves a random component. There's a good
discussion
>of this in Dawkins' <Climbing Mount Improbable> starting round abouts p.
79.
>Let me just quote a few of the concluding sentences of that discussion:
>
>"One way to dramatize the adequacy of non-random selection is to emphasize
>that mutation is *allowed* by the theory to be random. But, as I said
before,
>it is not critical to the theory that mutation *must* be random, and it
most
>certainly provides no excuse to tar the whole theory with the brush of
>randomness.
>Mutation may be random, but selection definitely is not." -- Dawkins
I think the reason most evolutionists say that selection is not random is
that, to most people, the word "random" means that all possible outcomes are
equally probable. And selection events are not equiprobable. Fitter
individuals are more likely to be selected. But a random variable is still
random if it has a non-uniform probability distribution.
Natural selection results from the different reproduction rates of different
individuals and species. But these reproduction rates are influenced by
random events as well as by biological fitness. Even the fittest gazelle in
a herd may have the misfortune to fall prey to a lion through no fault of
its own, and die without offspring, while its less fit neighbour lives to a
ripe old age and has many. Whole species may be wiped out by a cometary
impact.
>I think its also useful to point out once again that the randomness is with
>respect
>to utility.
Agreed. The impact of a comet may be non-random with respect to astronomical
considerations (at least if one considers a period which is too short for
chaos theory to come into play), but is random with respect to the fitness
of gazelles.
>Even the mutation element of evolution is not random in the
>statistical
>sense of the word.
Ah... so you disagree with Dawkins quote that you gave above. Good. The
difference between us is a semantic one over the meaning of the word
"random". At least we're each using the word consistently. But I think
Dawkins is being inconsistent here. (Or maybe he's using "random" in a third
sense, different from both of ours!)
Also, I'm confused by your use of "random in the statistical sense of the
word." Have you been using "random" in two different senses? Please clarify.
>Since there is a disagreement here on this basic point it will be useful to
>define what
>is meant by random. The definition I like best comes from algorithmic
>information
>theory and was developed largely by Chaitin whom I've mentioned before.
>This definition
>overcomes some difficulties (which I won't go into) with the definition
>from probability
>theory.
Oh, please do go into them. I don't know what difficulties you're referring
to, but perhaps they're central to this discussion.
>In fact, these difficulties were one of Chaitin's motivations for
>pursuing this.
>
>I don't want to get bogged down in details, but basically randomness has to
do
>with patterns. If something has a pattern, then it is not random.
I don't see what this has to do with the statistical notion of randomness.
You seem to be simply defining random to mean unpatterned. In that case, I
have to ask what you mean by a pattern, and what it has to do with
probability theory.
As far as I can see, a pattern is simply what we observe. We can argue about
whether the pattern was produced by a random process or not, but then we're
adopting my perspective of looking at the randomness of the process, rather
than of the result. And random processes certainly can produce patterns.
I don't know what Chaitin was referring to, but I suspect it was something
to do with testing whether a particular sequence of digits was generated by
a particular probability distribution, say a sequence of identical
independently distributed random variables. In that case, again, we're
talking about the randomness of the process, not of the result.
I suppose you could take a frequentist approach and ask about the randomness
of the end result by considering multiple trials and seeing whether they
produce different results. Unfortunately, that's not practical in the case
of evolution. But I think most evolutionists would agree that if we could
start the evolutionary process all over again, we would not get exactly the
same result. If they're right, then, in the frequentist sense, the outcome
of evolution was random.
>So, by your
>own admission in your comments above, evolution is not random according
>to this definition of randomness. Note also that an advantage this
>definition is
>that it is objective.
Not unless you have an objective definition of "pattern"!
>There is no talk of purpose, meaning etc. I could not
>say,
>for example, that evolution is not random, therefore it is purposeful.
>Questions
>like that cannot be dealt with objectively.
There are actually three possibilities: a process can be deterministic,
random or purposeful. If you take a deterministic view of free will, you
might reduce that to two (eliminating purposeful), but I don't want to beg
that question. I'm also simplifying, because a process may include a
combination of these three elements. (And I've argued before that there's no
such thing as a purely random process. All processes have some element of
determinism, provided by the laws of physics.)
Again, I'm back to talking about the process, not the end result. If you
insist on talking about end results being random, without consideration of
the processes which formed them, you're going to have to explain just what
you mean.
>RW:==
>> >Let's get back to my engineer. Here the "designer" sets up the
simulation
>> >and lets it run without interference. Whether the result is "designed"
>>depends
>> >upon the definition of design, as I've shown above. But one can hardly
>>argue
>> >that it is without purpose or plan.
>>
>>I agree that there may be a purpose and plan behind the *result*. But I
was
>>referring to the events making up the process. Each individual event is
>>unplanned and purposeless.
>>
>>Perhaps the difference between us is whether we're talking about proximate
>>purpose or ultimate purpose. I suppose the random events, while
individually
>>purposeless, are collectively contributing to the engineer's ultimate
>>purpose. So, in that sense, I suppose they could be said to have a
purpose.
>>But I think that's a weak sense.
>
>But the random element in this "design" process is the key. Perhaps the
best
>way of speaking of it is as a tool.
OK. I can accept that. ;-)
>RW:==
>>It might help if you would clarify what your position is on intelligent
>>agency. Do you think there has been intelligent direction in the
>>process of evolution, or only in setting up the initial conditions? If you
>>think there has been intelligent direction in the process of evolution,
>>then I don't think you fully accept the theory of evolution.
>
>hmmm.... :). That this seems such an important issue indicates to me
>that it is evolutionism of which you speak rather than the scientific
>theory of evolution.
Please clarify what you mean by evolutionism. Do you consider yourself a
theistic evolutionist?
>Anyway, I've discussed this point in the past. Let me just give a link
>to the archives.
>
>http://www.calvin.edu/archive/evolution/200005/0236.html
Strange... I don't recognize that post and I don't seem to have replied to
it. I must have overlooked it. I certainly would like to reply to it. Would
you like to resume that discussion?
In the meantime, I note that one of the possibilities you were willing to
consider is the following:
"(3) The image of God has to do with soul and spirit, rather than body.
"In this view, the physical body of man is not pre-ordained. Evolution
proceeds
until God finds a suitable result. He then breaths his spirit into the
species
he so chooses."
So it seems you're prepared to consider the possibility that God did not
intervene in the process of evolution (if we consider the addition of
spirit--whatever that is--to be separate from evolution).
>Your comment about fully accepting the theory of evolution reminded me
>of a quote of Dembski that I saw on the asa listserve:
>
>"Not to put too fine a point on it, the Darwinian establishment views
>theistic evolution as a weak-kneed sycophant that desperately wants the
>respectability that comes with being a full-blooded Darwinist but refuses
to
>follow the logic of Darwinism through to the end. It takes courage to give
>up the comforting belief that life has a purpose. It takes courage to live
>without the consolation of an afterlife. Theistic evolutionists lack the
>stomach to face the ultimate meaninglessness of life, and it is this
failure
>of courage that makes them contemptible in the eyes of full-blooded
>Darwinists." William Dembski, in _Intelligent Design_, InterVarsity Press,
>p. 112.
>
>Is this what you mean by fully accepting?
What I mean is that the theory of evolution, as I understand it, is based on
random, undirected variation and natural selection. I think Darwin wrote
that, if he thought intelligent direction was needed at any point in the
process of evolution, then he would consider the whole theory worthless.
(I'm sorry I can't find the quote at the moment.)
Dembski's point about "sycophants" and "respectability" is just the sort of
propaganda that we expect from IDers. If anyone sees TEs in this light, it's
IDers, like Phillip Johnson. Personally, I'm sure that the reason TEs accept
the theory of evolution (in so far as they do) is because that's the way the
evidence leads.
I do have my doubts about whether the TE position is tenable, but then I'm
still struggling to understand what that position is.
>It might be tempting to say that Dembski is misrepresenting his opponents.
>Actually, I do not think he is. In his excellent book <Finding Darwin's
God>,
>Kenneth Miller devotes a chapter to this type of thing, "The God's of
>Disbelief".
>He sets up this chapter in the following way:
>
>"By and large, the critics of evolution are not cynical opportunists. They
>aren't stupid, and they certainly understand how strong the scientific
>evidence is against them. So, why do they oppose evolution with such
>passion and persistence? I think I know, and as we shall see in the
>next chapter, many of my scientific colleagues, so baffled at the strength
>and depth of anti-evolution feelings in the U.S., would be surprised to
>discover that they are themselves a large part of the reason why." --
Miller
>
>Lest there is any confusion, Miller is a rather ardent Darwinist.
I'm trying to avoid the term "Darwinist", since there's so much confusion
about it (as seen in recent posts). I think I'll use the term "mainstream
evolutionary theorist" in future, or some variation on that.
>Anyway, I think Miller's criticism is fair and appropriate.
It may be that people like me, who find it impossible to reconcile the
theory of evolution with theistic direction of evolution, make it more
difficult for some people to accept the TOE. But I guess that's the price of
honestly saying what we really think.
>How is it that my position differs from someone like Phil Johnson? Phil
wants
>to drive a wedge between science and naturalistic philosophy. I'm all for
this.
>We would differ in that I would prefer the wedge to be indiscriminate. I
would
>want the wedge to separate science from all philosophy and theology as
well.
>Further, I think we already have a good wedge for this purpose,
methodological
>naturalism. I believe this wedge to be working pretty well in science
>itself, where
>it sometimes gets put aside is in the presentation of science to the
public.
I don't think science can be entirely divorced from philosophy, because
science is itself based on a philosophy. That's why we talk about the
"philosophy of science".
And I've yet to see any good reason why divine intervention should be given
a privileged (or underprivileged) position, placing it outside the bounds of
science.
>Another difference is this. Phil believes that something like Darwinism can
be
>maintained only by an a-priori commitment to naturalism. Thus, in effect,
>Phil's wedge is being inverted to make a hammer, at least when it comes
>to Darwinism. I believe, on the other hand, that naturalistic philosophy
can
>be stripped away leaving Darwinism as a scientific theory.
>
>To be clear, let me say that if I ever came to the conclusion that I have
>been wrong about this. If evolution really does mean all the things that
>some of these folks say that it means, then I'll immediately become
>a supporter of Phil Johnson and ID, as I once was.
I don't think that would be necessary. You could reject the theory of
evolution without claiming, as IDers do, to have a scientific basis for that
rejection. I think perhaps you're confusing the ID hypothesis with the
alleged scientific arguments in support of it. The hypothesis may be true
(though I personally doubt it). But the arguments are quite simply invalid.
Richard Wein (Tich)
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