Copyright © 2000 by Ron Yezzi

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Commentary on Michael Behe's Book, Darwin's Black Box

In the middle of the nineteenth century, Charles Darwin could not look into the black box of molecular biochemistry. But that situation no longer holds for the late twentieth century. Numerous scientists peer into the box; and they reject Michael's Behe's contention that molecular biochemistry points to irreducibly complex systems--only explainable through intelligent design and not explainable through evolution.

They also reject his claim that the scientific establishment ignores issues relating to molecular biochemistry and molecular evolution. One website,

http://www.talkorigins.org/faqs/behe.html

lists more than 160 specific references on these issues, as a counter to Behe's claim. The issues also have filtered into the textbook literature. For example, in a section on "The Physical and Chemical Framework," Monroe Strickberger's Evolution, a standard text, contains three chapters on molecular biochemistry and evolution--Molecules and the Origin of Life, Proteins and the Genetic Code, and From Metabolism to Cells. (There also is a later chapter on Molecular Phylogenies and Evolution.)

Most scientists do not quarrel with Behe's account of the complexity of systems such as blood clotting; but they disagree with his claim that these systems are irreducible and in need of explanation through intelligent design. First, they do not see a need for a leap to an ultimate explanation in terms of intelligent design when molecular biochemistry is a relatively young scientific field trying to understand some four billions years of evolution on earth. Secondly, given what scientists already know about evolutionary processes, there are a number of hypotheses that have not been eliminated to explain the complex systems considered by Behe. Moreover, these hypotheses have significant evidential support. And thirdly, the Neo-Darwinian, or Modern Synthesis, Theory of Evolution has accumulated so much ever-increasing supporting evidence over the past century and a half that it is more reasonable to treat Behe's described "irreducibly complex" systems as mysteries to be solved rather than as unsolvable problems that demand rejection of evolution and acceptance of intelligent design.

Behe's case for the irreducibility of complex systems such as blood clotting rests upon the argument that the parts of the system are so functionally interacting that they could not develop through gradual steps in an evolutionary process. The parts only make sense in terms of their functioning as a whole; hence improvement of a part prior to the functioning of the whole is impossible. Therefore the functioning of the whole through intelligent design is a necessary condition for the existence of these complex systems.

There are several hypotheses however, from the standpoint of evolution, that can explain the origin of these complex systems.

(a) Improvement of a More Primitive System - There could have been a primitive blood clotting mechanism in the evolutionary past that was improved into the more complex cascade that Behe describes. Blood clotting at the molecular level might be similar to eye structure at the anatomical level--where different kinds of organisms through different evolutionary paths developed lens systems of differing degrees of complexity, with some improving in functional effectiveness over time. One commentator faults Behe for apparently not looking for different blood clotting systems in other species, since that might indicate evolutionary improvement from ancient ancestry.

(b) Integration of Independently Evolved Parts - A part developed separately through one evolutionary path could join with another part fortuitously "to form a new selective regime in which the parts acquire (and then grow into) new functions." The philosopher Daniel Dennett, author of Darwin's Dangeous Idea: Evolution and the Meanings of Life, supports this claim by using the example of mitochrondia, according to Lynn Margulis' widely accepted theory that they began as independent bacterial cells. Dennett says, "The mitochrondia, which are little energy-machines in each cell of your body, are just such invaders, who, having evolved on their own, joined forces to form eukaryotic cells [cells associated with cell metabolism]." (Dennett's review of Behe's book can be found by checking items for 1997 at http://ase.tufts.edu/cogstud/papers/behe.htm )

(c) Gene Duplication Leading to Improvements that Later Become Essential Functions - H. Allen Orr, a biology professor at the University of Rochester whose specialty is evolutionary genetics, argues that "An irreducibly complex system can be built gradually by adding parts that, while initially just advantageous, become--because of later changes--essential." For example, "The transformation of air bladders into lungs that allowed animals to breathe atmospheric oxygen was initially just advantageous: such beasts could explore open niches--like dry land--that were unavailable to their lungless peers. But as evolution built on this adaptation (modifying limbs for walking, for instance), we grew thoroughly terrestial and lungs, consequently, are no longer luxuries--they are essential." What makes this hypothesis especially powerful, according to Orr, is the fact that genes produce duplicates of themselves that have no immediate function but are available for mutations that over time can develop advantageous functions that first appear as improvements and later become essential. He specifically mentions the role of gene duplication with respect to myaglobin and hemaglobin. The importance of gene duplication in explaining evolution of complex processes is also evident in comments on Darwin's Black Box by Russell Doolittle, whom Behe described as the most prominent scientist dealing with the blood clotting cascade. (Orr's review of Behe's book can be found at http://bostonreview.net/BR21.6/orr.html )

While Behe gives reasons for rejecting hypotheses like (a) and (b), he has not satisfied his scientific colleagues that these hypotheses are inadequate and hence that a leap to intelligent design is necessary.

Commentators on Behe's book also criticize his choice of illustrative examples for intelligent design--for example, a mousetrap, a bicycle factory turning into a motorcycle factory, and Mount Rushmore--as begging the question-at-issue. These examples are obvious instances of intelligent design because they involve planned human activities. But the natural world is not a planned human activity. So his examples provide misleading analogies that incline readers toward acceptance of intelligent design. In that sense, they merely restate the old design argument for God's existence, "If you discovered a watch on a deserted island, . . ." The real question is whether or not science, in studying nature, must rely upon intelligent design for explanation. And the prevailing answer of the scientific community is, "No."

In Behe's case, we also can raise questions about what would constitute sufficient confirmation of intelligent design. Convinced that intelligent life exists elsewhere in the universe on the basis of our knowledge of evolution and astronomy, scientists and engineers associated with SETI (Search for Extra-Terrestial Intelligence) have begun various projects to establish contact--for example, by transmitting messages into space about fundamental physical constants in the hope of establishing some likely basis for communication. Successful establishment of communication would be the best confirmation of the existence of extra-terrestial intelligence. If Michael Behe argues for intelligent design solely on scientific grounds, as he claims, is it not reasonable to require him to plan projects that scientifically establish communication with the intelligent designer(s)? Is there any scientific reason to think that his intelligent designer(s) would be any more reticent than the intelligent beings sought through SETI? Given Behe's insistence that irreducibly complex systems require intelligent design and that these systems exist on earth, is there not all the more reason to think that contact with the designer(s) is a plausible scientific project? Rather than projecting the existence of intelligent design through a questionable elimination of other hypotheses, Behe could meet a much higher standard of confirmation--and thereby establish a really significant probability for his hypothesis--by establishing scientific communication with the designer(s). Moreover, the absence of an attempt to establish this communication is a probable indicator of religious convictions merged with allegedly scientific reasoning. That is, Behe expresses no desire to establish scientific communication for purposes of sufficient confirmation because his position has a religious foundation. Communication with the designer in religious ways--through revelation, prayer, and religious experiences--takes the place of scientific communication. Accordingly, it is questionable whether he is proceeding scientifically.

Additional References Related to the Commentary and to the Feb. 28, 2007 My View Column in the Free Press

My Background: Although I have a B.S. in physics (long enough ago that I would be embarrassed to admit how much I’ve forgotten), most of my training and experience lies in philosophy. So I am not claiming to be a scientist. I have some background in the philosophy of science, and for years, taught a course in the logic of scientific method. I used my own text, Logical Methods and Standard Scientific Explanation, which included a chapter on Creationism and Evolution. I’ve followed the issue over time. I think that what I say here accurately reflects the position of the overwhelming majority of the scientific community. The works on intelligent design by creationists do not appear in the reputable scientific journals and they are not part of the content in science textbooks.

            Three Relatively Recent Books Responding to Claims About Intelligent Design:
            Matt Young and Taner Edis, eds., Why Intelligent Design Fails: A Scientific Critique of the New Creationism (New Brunswick: Rutgers University Press, 2004)
            Victor J. Stenger, Has Science Found God?: The Latest Results in the Search for Purpose in the Universe (Amherst: Prometheus Books, 2003)
            Kenneth R. Miller, Finding Darwin’s God: A Scientist’s Search for Common Ground Between God and Evolution (New York: HarperCollins Publishers, 1999). Miller, a biologist and Roman Catholic, rejects intelligent design positions as science, although he also explains why he is a religious person.

Some Comments on Sources in Doug Wolter’s Jan. 20 Column: I think that his column is misleading in suggesting scientists have now come around to questioning previous assumptions about origins and are concluding that the universe requires intelligent design. While there may be a small number of individuals with scientific credentials making these claims, it is a fringe view, not a prevailing view. And the one intelligent design proponent he mentions, Gerald Schroeder, is way out on the fringe.

The only work cited by Doug Wolter in his Jan. 20 column is Gerald Schroeder’s The Science of God. You can find his splashy homepage at
http://www.geraldschroeder.com But for a criticism of his work, go to the critique by physicist and mathematician Mark Perakh at
http://www.talkreason.org/articles/schroeder.cfm The section, “Schroeder Estimates Probabilities,” is especially useful.

For an Aug. 11, 2006 news report on the study testing acceptance of evolution, go to
http://www.foxnews.com/story/0,2933,207858,00.html

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Last updated 2/21/07