Two Questions about Complexity
In Darwin's Black Box: The Biochemical
Challenge to Evolution (1996), Michael Behe illustrates the principle of irreducible
complexity with a mousetrap that has five interacting parts: a base, hammer,
spring, catch, and holding bar. Each part is necessary, and there is no
function unless all parts are present. A trap with only four parts has
no practical function. It doesn't just catch mice poorly, it doesn't catch
them at all.
What are the implications
for biological evolution? Behe
says, "An irreducibly complex system cannot
be produced directly... by slight, successive modifications of a precursor
system, because any precursor to an irreducibly complex system that is
missing a part is by definition nonfunctional. An irreducibly complex
biological system, if there is such a thing, would be a powerful challenge
to Darwinian evolution." (Darwin's Black Box, page 39)
For a nonliving system,
the implications are even more challenging, because natural selection — which
is the main mechanism of Darwinian evolution — cannot exist until
a system can reproduce. For an origin of life by chemical
evolution, what minimal complexity would
be required for reproduction and other essential life-functions?
Let's look at responses
to these two questions.
When is
critical thinking unscientific?
To explain the minimal
complexity required in a natural origin of life, scientists
have proposed many theories about
the origin of life but — since what
is required for life seems
greater than what is possible by natural process — currently
each theory seems implausible. Supporters of one theory point out
the weakness in other theories, and their critical thinking is welcomed
by the scientific community.
What would make their critical
thinking unscientific? a claim that a natural formation of life is
extremely improbable, and maybe impossible? a perception (by others)
that this claim implies a non-natural cause? an explicit proposal
for a non-natural cause? Is there any limit to the severity of criticism
before it becomes unscientific? If all non-design theories are criticized
and there is a proposal for design-directed action, is this unscientific? If
severe criticism is accompanied by a proposal for a naturalistic theory,
does this make it scientific?
Can scientists admit
that "we are far from finding the answer" but not that "maybe
there is no natural answer"? Consistent with the restrictions
of methodological naturalism,
should we control the thinking of scientists by removing their
freedom to think that "maybe..."?
Should
questions be in scientific journals?
When Michael Behe submitted papers about irreducible
complexity to science journals, he found that some individual editors
were interested,
but
groups were intolerant. One editorial board concluded its rejection letter, "Our
journal... believes that evolutionary explanations of all structures and phenomena
of life are possible and inevitable." { In the next
section, you
can
see details about Behe-and-journals. }
In an open-minded free
science, the response would be different. Behe's thought-provoking
questions would be welcomed as a constructive challenge, an opportunity
to gain a more complete understanding of evolution at the molecular
level. The journals would be eager to communicate new ideas,
to host invigorating debates between critics of a theory and its
loyal defenders.
Should
we ask questions?
In the near future,
scientists will disagree about the plausibility and utility of design,
but conflicts in science are common and can be productive. Should
journal editors wait until proponents of design have irrefutable
proof? Because proof
is impossible in science it can be difficult to confidently answer the
question, "Was design-action involved in producing this feature?" But
it should be easy to decide, "Should we ask the question?" A
curious, open-minded community will say "YES, we want our science
to be flexible and open to inquiry, not rigid and closed by dogmatism.
Mike Behe's Adventures in Non-Publishing
the context: Design theorists have raised
a variety of questions about the plausibility of neo-Darwinian evolution. For
example, in Darwin's Black Box: The Biochemical Challenge to Evolution (1996),
Michael Behe claims that some biochemical systems are irreducibly complex and
probably could not be produced in the step-by-step process that is proposed
in current neo-Darwinian theories.
a possibility: Consistent
with the standards of modern molecular biology, Behe is encouraging a detailed
examination of evolution, at a deeper level with higher standards. As
expected, his challenges have stimulated creative thinking and experimenting
among individual scientists who read his book or heard about his ideas
in subsequent reviews, lectures, or internet debates. His critical
questions have served as a catalyst for action by defenders of evolution
who want to show he is wrong, and by proponents of design.
the reality: When he
submitted papers about irreducible complexity to science journals, what
was the response? Behe summarizes: "While
some science journal editors are individually tolerant and will entertain
thoughts of publishing challenges to current views, when a group (such
as the editorial board) gets together, orthodoxy prevails." {
In this section, all quotations are from Correspondence
with Science Journals: Response to Critics concerning Peer-Review by
Michael Behe. }
For example, one editor
described a problem: "I am painfully aware
of the close-mindedness of the scientific community to non-orthodoxy,
and I think it is counterproductive." Behe's submission
was sent to a senior journal advisor, who responded to Behe's critical
analysis with a proposal for delayed publication: "Having
not yet understood all of biology is not a failure after just 200 years,
given the amount of understanding already achieved. Let us speak
about it again in 1000 years." The editor, in rejecting
Behe's paper, said "I would like to encourage
you to seek new evidence for your views, but of course, that evidence
would likely fall outside of the scientific paradigm, or would basically
be denials of conventional explanations. You are in for some tough
sledding."
With another journal, after
Behe submitted a tightly focused paper (a reply to specific criticisms)
the editor graciously proposed an expanded project that — consistent
with the noble ideals of science — would have performed a valuable
service by encouraging the open discussion of an exciting new idea:
"The
notion of intelligent design is one that may warrant further exploration,
even though the topic has been dealt with extensively by both practicing
scientists and philosophers of science. Should this exploration
take the form of contrasting viewpoints in articles by two persons,
published in the same issue, on the more general aspects of the topic,
then our editorial policy of presenting current issues of significance
in the biological sciences might be satisfied. / Recast
in more general terms, your article could present the "pro" side
of the issue, and in that context it could address some of the criticisms
that have appeared since your book was published, but it would have
to provide a much broader perspective. In particular, it would
have to assume a readership that is not familiar with your book,
at least not in any detailed way. An accompanying article could
present the "con" side of the issue, again taking a general
perspective. No doubt your book would figure prominently in
both articles, but the theme would be modern concepts of intelligent
design rather than a specific publication. This approach would
almost certainly reach a broader readership than a detailed response
to specific criticisms. It also has the added advantage of
allowing you to present a synopsis of your entire case rather than
just defending specific aspects of it. Such a paired set of
articles would imply that the topic is important, and therefore would
attract additional readers."
This is an excellent "open
science" approach. But the journal's editorial board was less
enthusiastic. They protested that "it
is not possible to develop a meaningful discussion" between
a design theory "based on intuitive, philosophical,
or religious grounds" and an evolutionary theory "based
on scientific fact and inference." And they concluded, "Our
journal... believes that evolutionary explanations of all structures
and phenomena of life are possible and inevitable. Hence a position
such as yours, which opposes this view on other than scientific grounds,
cannot be appropriate for our pages. Although the editors feel
that there has already been extensive response to your position from
the academic community, we nevertheless encourage further informed discussion
in appropriate forums. Our journal cannot provide that forum, but
we trust that other opportunities may become available to you."
Analysis — Comparing
the Actual and Ideal
If all questions about
biological evolution have been answered, if the ideas of Mike Behe
have no scientific merit and his claims already have been proved
false,
then his ideas should be excluded from science journals. But
if he asks questions that might raise doubts about some aspects of
current theories, there is a reason to include his ideas in journals.
An editor informally
recognized that "there has already been
extensive response to your position from the academic community," but
official recognition (by publication in their journal) was denied. Why? They
explained that, in contrast with Behe's intuitive religious philosophy,
their journal contains pure science. But the situation seems
reversed. Although Behe's ideas are based on observations and
scientific logic, publishing them "cannot
be appropriate" because "our
journal... believes that evolutionary explanations... are possible
and inevitable." The rejection seems to be based
on philosophical preference, not scientific merit.
But according to a noble
ideal of objective science — operating in a community of curious,
open-minded scientists who are exploring freely, are thinking critically,
creatively, and flexibly, and are dedicated to finding the truth — the
response should be different. Ideally, instead of ignoring the
concept of design, pretending it doesn't exist and trying to exclude
it from the mainstream of science, its tough questions would be carefully
examined and used as a stimulus for productive action.
Instead, critical questions
are resented and rejected. This response does offer a practical
benefit, by letting a community defend its reigning paradigm. But
if a defense is based on preventing questions rather than answering them,
this does not seem consistent with the lofty ideals of scientists, with
their noble vision of science as an intellectually free, objective pursuit
of truth. Instead, in a community of scientists who are exploring
freely, thinking flexibly, and dedicated to finding truth, Behe's tough
questions would be used as a stimulus for critical analysis, creative
thinking, and productive action.
Perhaps, when the evidence
and arguments have been thoroughly examined and debated, when more experiments
and analyses have been done, Behe's ideas will be shown to be wrong. But
critical thinking should be allowed in science, so there should at least
be some recognition — by allowing publication in science journals — that
his questions are important and are worthy of being asked.
Reasons
for Rejection? (freedom and responsibility)
For an editor, two goals — academic
freedom and editorial responsibility — can be in tension. Typically,
editors want to promote a free exchange of ideas, but they have a responsibility
to avoid promoting ideas that lack scientific support, are inappropriately
speculative, or might hinder overall scientific productivity. When
deciding whether or not to include a particular article in a journal, an
editor considers a variety of factors: writing quality, scientific
quality, the claims being made and their support by evidence and logic, potential
contributions to overall scientific productivity and the development of current
maxi-theories (as discussed below), compatibility with the goals and scope
of a journal, supply-and-demand (ratio of articles submitted to space in
journal), whether it "fulfills a function" for the journal, and
so on.
What factors are involved
in a particular editorial decision, or a "pattern of decisions" in
a field? These questions are difficult to answer with confidence,
due to the complex interactions of multiple factors (psychologically within individuals,
and sociologically in their communities) that are examined by authors with a wide range of opinions. The principle below will be useful in
our discussions.
Defending
a Theory (maxi-theories and mini-theories)
Del Ratzsch — in Science & Its
Limits: The Natural Sciences in Christian Perspective (2000) — explains
why some theories, but not others, are vigorously defended against empirical
falsification:
We must
distinguish at least two levels of theory. One level (variously called "maxi-theories" or "research
programmes" or "research traditions") comprises the broad
conceptual frameworks within which the day-to-day activity of science takes
place. The other level consists of the more detailed specific theories
that are attempts to deal with particular phenomena within the constraints
imposed by the maxi-theories. . . .
Maxi-theories usually encompass
many specific theories covering a broad range of phenomena. And
if many of the specific theories are highly confirmed, the maxi-theory
under which they operate is also strongly supported and therefore has
sizable empirical inertia. Thus there is usually good reason
for reluctance to abandon it and good reason to hope that apparently
contrary data may eventually be shown to have interpretations acceptable
within the bounds of the maxi-theory. . . .
On the other hand, the
specific mini-theories are much more subject to the immediate effects
of empirical data. They are, again, simply attempts to solve
problems within the broader framework set by the maxi-theories. If
one such attempt does not work, perhaps another will. Science
often has little historical investment in any particular one of them,
and if the data tend to show that one of them is inadequate, the loss
to science is minimal. No other part of science need be affected. But
a maxi-theory is a synthesizing, simplifying and unifying factor within
science, bringing numerous mini-theories into a system of shared fundamental
principles. So abandonment of a maxi-theory would turn a previously
conceptually unified area of science into a disorganized collection
of isolated, independent, unrelated mini-theories without common conceptual
anchors. . . .
Thus some theories are
rejected straightforwardly on the basis of contrary data, and some
theories persist in the face of such data. But the theories in
those respective categories tend to operate on different scales and
play different roles within science. { excerpts quoted
from Science & Its Limits, pages 64-65 }
Here is a description of thought
styles, which include maxi-theories and more, from Part
8 of my model for Integrated Scientific Method: "A
collective thought style includes the
shared beliefs, among a group of scientists, about ‘what should
be done and how it should be done.’ Thought styles affect
the types of theories generated and accepted, and the problems formulated,
experiments done, and techniques for interpreting data. There
are mutual influences between thought styles and the procedural ‘rules
of the game’ that are developed by a community of scientists, operating
in a larger social context, to establish and maintain certain types
of institutions and reward systems, styles of presentation, attitudes
toward competition and cooperation, and relationships between science,
technology, and society. ... Thought styles affect the process and content of
science."