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What is Intelligent Design?STEPHEN C. MEYERIn December 2004 New Mexico Public Television scheduled, advertised and then, under pressure, canceled a documentary explaining the scientific case for a theory of biological origins known as intelligent design.
Also in December, the ACLU
filed suit to prevent a Dover, Penn. school district from informing its students
about the theory of intelligent design. As
one of the architects of the theory of intelligent design, and the director a
research center that supports the work of scientists developing the theory, I
know that it isn't.
The modern theory of intelligent design
was not developed in response to a legal setback for creationists in 1987. Instead,
it was first formulated in the late 1970s and early 1980s by a group of scientists
Charles Thaxton, Walter Bradley, Roger Olson, and Dean Kenyon who
were trying to account for an enduring mystery of modern biology: the origin of
the digital information encoded along the spine of the DNA molecule. Over
the last 25 years, scientists have discovered an exquisite world of nanotechnology
within living cells. Inside these tiny labyrinthine enclosures, scientists have
found functioning turbines, miniature pumps, sliding clamps, complex circuits,
rotary engines, and machines for copying, reading and editing digital information
hardly the simple "globules of plasm" envisioned by Darwin's contemporaries.
Is this appearance of design merely illusory? Could natural selection have produced this appearance in a neo-Darwinian fashion one tiny incremental mutation at a time? Biochemist Michael Behe argues 'no.' He points out that the flagellar motor depends upon the coordinated function of 30 protein parts. Yet the absence of any one of these parts results in the complete loss of motor function. Remove one of the necessary proteins (as scientists can do experimentally) and the rotary motor simply doesn't work. The motor is, in Behe's terminology, "irreducibly complex." This creates a problem for the Darwinian mechanism. Natural selection preserves or "selects" functional advantages. If a random mutation helps an organism survive, it can be preserved and passed on to the next generation. Yet, the flagellar motor has no function until after all of its 30 parts have been assembled. The 29 and 28-part versions of this motor do not work. Thus, natural selection can "select" or preserve the motor once it has arisen as a functioning whole, but it can do nothing to help build the motor in the first place. This leaves the origin of molecular machines like the flagellar motor unexplained by the mechanism natural selection that Darwin specifically proposed to replace the design hypothesis. Is
there a better alternative? Based upon our uniform and repeated experience, we
know of only one type of cause that produces irreducibly complex systems, namely,
intelligence. Indeed, whenever we encounter irreducibly complex systems
such as an integrated circuit or an internal combustion engine and we know
how they arose, invariably a designing engineer played a role.
The strength of Behe's design argument can be judged in part by the response of his critics. After nearly ten years, they have mustered only a vague just-so story about the flagellar motor arising from a simpler subsystem of the motor a tiny syringe that is sometimes found in bacteria without the other parts of the flagellar motor present. Unfortunately for advocates of this theory, recent genetic studies show that the syringe arose after the flagellar motor that if anything the syringe evolved from the motor, not the motor from the syringe. But consider an even more fundamental argument for design. In 1953 when Watson and Crick elucidated the structure of the DNA molecule, they made a startling discovery. The structure of DNA allows it to store information in the form of a four-character digital code. Strings of precisely sequenced chemicals called nucleotide bases store and transmit the assembly instructions the information for building the crucial protein molecules and machines the cell needs to survive. Francis Crick later developed this idea with his famous "sequence hypothesis" according to which the chemical constituents in DNA function like letters in a written language or symbols in a computer code. Just as English letters may convey a particular message depending on their arrangement, so too do certain sequences of chemical bases along the spine of a DNA molecule convey precise instructions for building proteins. The arrangement of the chemical characters determines the function of the sequence as a whole. Thus, the DNA molecule has the same property of "sequence specificity" that characterizes codes and language. As Richard Dawkins has acknowledged, "the machine code of the genes is uncannily computer-like." As Bill Gates has noted, "DNA is like a computer program, but far, far more advanced than any software we've ever created." After the early 1960s, further discoveries made clear that the digital information in DNA and RNA is only part of a complex information processing system an advanced form of nanotechnology that both mirrors and exceeds our own in its complexity, design logic and information storage density. Where did the digital information in the cell come from? And how did the cell's complex information processing system arise? Today these questions lie at the heart of origin-of-life research. Clearly, the informational features of the cell at least appear designed. And to date no theory of undirected chemical evolution has explained the origin of the digital information needed to build the first living cell. Why? There is simply too much information in the cell to be explained by chance alone. And the information in DNA has also been shown to defy explanation by reference to the laws of chemistry. Saying otherwise would be like saying that a newspaper headline might arise as the result of the chemical attraction between ink and paper. Clearly "something else" is at work. Yet, the scientists arguing for intelligent design do not do so merely because natural processes chance, laws or the combination of the two have failed to explain the origin of the information and information processing systems in cells. Instead, they also argue for design because we know from experience that systems possessing these features invariably arise from intelligent causes. The information on a computer screen can be traced back to a user or programmer. The information in a newspaper ultimately came from a writer from a mental, rather than a strictly material, cause. As the pioneering information theorist Henry Quastler observed, "information habitually arises from conscious activity." This connection between information and prior intelligence enables us to detect or infer intelligent activity even from unobservable sources in the distant past. Archeologists infer ancient scribes from hieroglyphic inscriptions. SETI's search for extraterrestrial intelligence presupposes that information imbedded in electromagnetic signals from space would indicate an intelligent source. As yet, radio astronomers have not found information-bearing signals from distant star systems. But closer to home, molecular biologists have discovered information in the cell, suggesting by the same logic that underwrites the SETI program and ordinary scientific reasoning about other informational artifacts an intelligent source for the information in DNA. DNA
functions like a software program. We know from experience that software comes
from programmers. We know generally that information whether inscribed
in hieroglyphics, written in a book or encoded in a radio signal always
arises from an intelligent source. So the discovery of information in the DNA
molecule, provides strong grounds for inferring that intelligence played a role
in the origin of DNA, even if we weren't there to observe the system coming into
existence.
Of course, many will still dismiss intelligent design as nothing but warmed over creationism or as a "religious masquerading as science." But intelligent design, unlike creationism, is not based upon the Bible. Design is an inference from biological data, not a deduction from religious authority. Even so, the theory of intelligent design may provide support for theistic belief. But that is not grounds for dismissing it. To say otherwise confuses the evidence for a theory and its possible implications. Many scientists initially rejected the Big Bang theory because it seemed to challenge the idea of an eternally self-existent universe and pointed to the need for a transcendent cause of matter, space and time. But scientists eventually accepted the theory despite such apparently unpleasant implications because the evidence strongly supported it. Today a similar metaphysical prejudice confronts the theory of intelligent design. Nevertheless, it too must be evaluated on the basis of the evidence not our philosophical preferences or concerns about its possible religious implications. Antony Flew, the long-time atheistic philosopher who has come to accept the case for design, insists correctly that we must "follow the evidence wherever it leads." ACKNOWLEDGEMENT Stephen C. Meyer, "What is Intelligent Design?" National Post, (Canada) 1 December, 2005. Reprinted with permission of the author, Stephen C. Meyer. THE AUTHOR
Copyright © 2005
Stephen C. Meyer
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