Intelligent Design – Response to Behe

November 2005
by Robert Novella & Steven Novella, MD

A Response to New York Times Op-Ed Promoting Intelligence Design by Michael Behe

Despite a string of past legal victories by defenders of evolution, supporters of creationism who deny evolution in favor of the notion that all life was divinely created are tireless and undaunted in their quest to teach their faith as science in public schools. In the past decade this effort has evolved into the Intelligent Design (ID) movement, and renewed efforts to infiltrate academia and public science education are underway.

This past February, Michael Behe, co-founder of the Intelligent Design (ID) movement, fired a volley for his cause by publishing an Op-Ed piece in the New York Times. In it he declared that Intelligent Design, offered by proponents as an alternative to Darwinian Evolution, is “based on physical evidence and a straightforward application of logic.” In concluding this statement he says that the argument for ID “consists of four linked claims.” Behe’s Op-Ed is a manifestation of the ID movement’s desperation to portray themselves as scientific – based upon logic and evidence, but simultaneously reveals ID to be anything but science.


Michael J. Behe is a professor of biological science at Lehigh University in Bethlehem Pennsylvania. His book “Darwin’s Black Box: The Biochemical Challenge to Evolution” thrust him into the forefront as one of the primary supporters of Intelligent Design in the late 1990’s. He is also a senior fellow of the Discovery Institute which is the primary promulgator of all things ID. This institute is well known for its leaked “Wedge” document that minutely outlines the steps required to topple scientific materialism and what they believe to be its stifling domination of worldview. Part of this process includes the battles currently taking place in Kansas and Pennsylvania to allow ID in the science classroom as a viable alternative to evolution. Some of the goals here are more than just teaching ID as real science; they are much more insidious.

In 1998 the Kansas board of education not only removed much of evolution from their science standards; they also removed mandates that students learn about the Big Bang theory, that the earth is older than 10,000 years, and plate tectonics. That decision was overturned when more science friendly board members were voted in the following year, but social conservatives have recaptured the Kansas school board and now they have successfully changed their science standards again. This time they are not requiring teaching of ID nor removing teaching of evolution, but rather are mandating that the “gaps and flaws” in evolutionary theory be taught. This strategy has been anticipated by defenders of evolution, who fear it will be more difficult to fight in court on first amendment grounds.

An important part of ID proponents broader strategy is to change the definition of Science itself. Scientific methodology is based upon finding natural explanations for observed phenomena – material causes for material effects. ID proponents claim that this stacks the deck against supernatural causes, and that scientific research should be free to consider all possibilities and let the chips fall where they may. Although superficially appealing to democratic sensibilities, this concept is incompatible with science. Scientific hypotheses must be testable and falsifiable. Supernatural causes, which by definition are unrestrained by the laws of nature, are impossible to falsify. It is no surprise, therefore, that ID proponents have no research program – there is nothing for them to do except snipe at evolution.

The Op-Ed

After a short preamble, Behe gets to the meat of his letter with the following:

“… the contemporary argument for intelligent design is based on physical evidence and a straightforward application of logic. The argument for it consists of four linked claims.”

This sounds rather straightforward and rigorous. An unsuspecting reader, upon reading this, might anticipate that what followed should be a logical argument describing the evidence to support Intelligent Design. Such hopes, however, are quickly dashed.

Claim #1

Behe then dives directly into his “four linked claims;” the first of which follows:

“The first claim is uncontroversial: we can often recognize the effects of design in nature. For example, unintelligent physical forces like plate tectonics and erosion seem quite sufficient to account for the origin of the Rocky Mountains. Yet they are not enough to explain Mount Rushmore.

Of course, we know who is responsible for Mount Rushmore, but even someone who had never heard of the monument could recognize it as designed.”

His assertion that the recognition of design in nature is uncontroversial is puzzling. Is he being disingenuous? This is most certainly controversial, and obviously so. In fact, it cuts to the heart of the entire Intelligent Design versus Evolution debate. If there were no controversy on this point there would be no debate.

Bringing in Mount Rushmore is equally puzzling and does nothing to bolster Behe’s argument. Mount Rushmore is not a natural object and therefore does not count as a “design in nature,” unless he counts the artifice of man as part of nature. Why not just list a truly natural object and describe how the effects of design are so evident. I even have an example for him. How about New Hampshire’s Old Man of the Mountain. This famous rock formation bears a remarkable resemblance to a man’s face in profile, and could arguably be said to “appear” designed.

Claim #2

…the physical marks of design are visible in aspects of biology. This is uncontroversial, too.

The 18th-century clergyman William Paley likened living things to a watch, arguing that the workings of both point to intelligent design. Modern Darwinists disagree with Paley that the perceived design is real, but they do agree that life overwhelms us with the appearance of design.

For example, Francis Crick, co-discoverer of the structure of DNA, once wrote that biologists must constantly remind themselves that what they see was not designed but evolved. (Imagine a scientist repeating through clenched teeth: “It wasn’t really designed. Not really.”)

The resemblance of parts of life to engineered mechanisms like a watch is enormously stronger than what Reverend Paley imagined. In the past 50 years modern science has shown that the cell, the very foundation of life, is run by machines made of molecules. There are little molecular trucks in the cell to ferry supplies, little outboard motors to push a cell through liquid.

In 1998 an issue of the journal Cell was devoted to molecular machines, with articles like “The Cell as a Collection of Protein Machines” and “Mechanical Devices of the Spliceosome: Motors, Clocks, Springs and Things.”

…Bruce Alberts, president of the National Academy of Sciences,… (has) remarked, the entire cell can be viewed as a factory with an elaborate network of interlocking assembly lines, each of which is composed of a set of large protein machines. He emphasized that the term machine was not some fuzzy analogy; it was meant literally.

This claim, that “marks of design are visible in aspects of biology,” is again characterized by Behe as “uncontroversial.” Again I must disagree. In Behe’s sense of the word “design” (implying a designer) there is great controversy. This is a more subtle version of his word-play tactics that are made more obvious in the remaining section of his second argument. In this section he describes biologist’s use of the word “machines” when describing components of cells. The hope here, it seems, was that many readers would automatically link the concept of a “machine” with “intentional design.” After all, aren’t the machines of every-day life designed by an intelligence…us. Sub-cellular machines should then have an intelligent designer as well.

The concept of a machine has become more generalized in the past fifty years or so. It used to be that any mention of a machine implied a human agency who created it. As the molecular revolution of the 1950’s ignited biological knowledge, the machine-like attributes of cells and their components became more evident, and it became increasingly common to refer to molecular assemblies in cells as machines. Indeed, the word “machine” at includes this as the fourth definition: “An intricate natural system or organism, such as the human body”2.

It’s not easy to think of people or cells as machines. I remember years ago telling my uncle that people were essentially machines; he was aghast at the suggestion. How can something so complicated and elegant be considered a machine? Part of the problem is that we’re accustomed to machines like back-hoes that are made of thousands of parts. We are not used to the conception of machines with billions of parts.

In short, Behe’s second argument is nothing more than a simple logical fallacy based upon semantics – the fact that some parts of a biological organism behave like man-made machines in that they can perform specific physical tasks, does not mean they must also share any other feature of man-made machines, such as being designed.

Claim #3

The next claim in the argument for design is that we have no good explanation for the foundation of life that doesn’t involve intelligence. Here is where thoughtful people part company.

Darwinists assert that their theory can explain the appearance of design in life as the result of random mutation and natural selection acting over immense stretches of time.

Some scientists, however, think the Darwinists’ confidence is unjustified. They note that although natural selection can explain some aspects of biology, there are no research studies indicating that Darwinian processes can make molecular machines of the complexity we find in the cell.

Scientists skeptical of Darwinian claims include many who have no truck with ideas of intelligent design, like those who advocate an idea called complexity theory, which envisions life self-organizing in roughly the same way that a hurricane does, and ones who think organisms in some sense can design themselves.

On to Behe’s third claim, the crux of which appears to be that there’s no good theory for the molecular machines “of life that doesn’t involve intelligence.” Finally we have an argument that he agrees is controversial. This controversy is, however, not a matter of “thoughtful people part(ing) company.” It’s really a matter of thoughtful people parting company from supporters of Intelligent Design or those just unfamiliar with the mountain of evidence for evolution.

The “complexity” that Behe finds so evolutionarily baffling is summed up in his concept of irreducible complexity which he introduced in his book “Darwin’s Black Box.” This hypothesis states that since certain cellular components or processes are structured such that the removal of any one component cripples it, then it could not have evolved in Darwinian step-wise fashion. The canonical example is a mousetrap. If any one piece is removed, be it the spring, the wood base, the hook etc, it becomes utterly useless. If mousetraps evolved in some biological sense, then how could it arrive at its current working state if innumerable antecedent states would have no utility? The rats would take over well before rat traps could evolve themselves into usefulness. The assumption of useless previous incarnations is, however, a critical premise of this argument and happens to be entirely wrong. Darwin himself pointed out the fallacy of this argument, a fact that calls into question the scholarship and/or intellectual honesty of anyone who would trot it out a century and a half later.

Behe has offered the bacterial flagellum as a candidate for irreducible complexity. This little outboard motor for bacteria spins at more than twenty thousand r.p.m.s. Remove just one of the thirty exquisitely arranged proteins that comprise this molecular machine and you’re stuck in the middle of the lake. But there is no reason within evolutionary theory to assume that the flagellum had to evolve directly to its current usage. Perhaps the flagellum proteins were used for another function and then co-opted for their current irreducibly complex role. Indeed, there is now compelling evidence that some of these crucial proteins were once used as part of a membrane pump in the cell walls of bacteria.

Gene duplication is another piece of positive evidence against irreducible complexity. Throughout our genome there exists duplicated genes and families of genes that apparently derived from one ‘grandfather” gene. Indeed, redundancy appears to be written all over our DNA. This offers a powerful tool for the evolution of genomes. A critical gene that becomes redundant is no longer in the strait-jacket of its host’s survivability. It is therefore free to evolve in novel directions; even producing an apparently irreducibly complex structure. So irreducible complexible is a non-problem for evolution, and in fact was partly solved by Darwin himself, but ID’ers either pretend such solutions do not exist or are blissfully ignorant of them.

A common knee-jerk tactic among pseudoscientists is also the logical fallacy called the “argument from ignorance.” For example, in the 1970’s it was commonly believed that the Egyptian and Central American pyramids were far beyond the engineering skills of the cultures that spawned them. Since construction methods using tools available at the time could not easily explain these impressive structures, it was argued that aliens must have had a hand (or tentacle) in their creation – without any positive evidence for alien involvement. Archaeologists soon figured out, however, how the clever application of simple materials could account for these feats of engineering. Now, except maybe for a small group of fringe believers, there is no doubt that these ancient cultures did indeed build these structures themselves. Behe’s assertion in claim number three is essentially the same: since we have no good theory for the evolution of biological complexity then it must have been designed by some external intelligence – but he and is ID colleagues have no positive evidence, or even a research agenda, to support the notion of a designer. Even worse, their premise – that evolution is inadequate to account for complex life, is false. However, they attempt to create the impression of unsolvable “gaps” in evolutionary theory by demanding scientific proof of every aspect of the evolution of life on earth, down to every last protein, or, they claim, evolution is not “proved” and we must invoke a supernatural designer. This is the argument from ignorance ad absurdum.

Behe also spends considerable time in his third claim on the fact that there are scientists who are skeptical of evolution, implying that there is serious scientific debate among scientists as to the utility of evolutionary theory. Creationists have been claiming for decades that academic support for evolution is on the brink of collapse, a claim that has become increasing untrue. There is no serious scientific debate about the fact of evolution (please read that sentence again if required). This is not dogma or arrogance but a consensus built upon multiple converging lines of extraordinary evidence. The relative contribution of different mechanisms within evolution are debated, as well as the exact evolutionary course of life on earth – but not the fact that life evolved. The same is true in most robust scientific disciplines – the technical minutiae of gravitational interactions are hotly debated but no one doubts the existence of gravity due to this internal debate. Scientists who doubt evolution are as much on the fringe as those who make perpetual motion machines or believe in mind reading.

Some will respond that evolution is just a theory after all and not proven. This point confuses scientific and lay terms and misses a key fact about science. Theory in science is a cohesive description of a phenomenon that attempts to make predictions. The lay usage of theory is more akin to “speculation” or “educated guess.” Scientific theories lie on a continuum from barely-supportable to damn-near-certain. Evolution is at the tail-end of the latter along with the theory of gravity and the heliocentric (sun-centered) theory of the solar system. One hundred percent proof of any theory is never a goal in science because unwarranted assumptions are always at least a remote possibility. The best we can do is mount the decimals to 100% certainty. Once an arbitrary line is passed a theory is justified in being called a fact. Evolution passed that line a long time ago and now resides in a realm where denial is perverse (as Stephen J. Gould put it).

Claim #4

The fourth claim in the design argument is also controversial: in the absence of any convincing non-design explanation, we are justified in thinking that real intelligent design was involved in life.

In this brief statement Behe manages to pack in a false premise and two logical fallacies. Again, it is decidedly non-controversial among scientists that there is an overwhelming accumulation of convergent evidence supporting evolution as a non-design explanation for life. Even if this were not so, however, Behe’s conclusion is invalid because his logic is fallacious. The first logical fallacy he commits is the False Dichotomy (if not a then b). What about c,d,e etc. There’s nothing stipulating that there are only two possible options – evolution or design.

Further, as described above he commits the argument from ignorance logical fallacy – the absence of an existing convincing non-design explanation means there is no non-design explanation and therefore it is reasonable to conclude that “design was involved.” This logical fallacy is, in fact, a major weakness of the ID edifice – a weakness which rots it to the core. ID is based entirely on the alleged absence of evidence for evolution, or alleged difficulties with current evolutionary models. ID proponents have nothing to offer which even approximates positive evidence for design.

Behe further writes:

…The strong appearance of design allows a disarmingly simple argument: if it looks, walks and quacks like a duck, then, absent compelling evidence to the contrary, we have warrant to conclude it’s a duck. Design should not be overlooked simply because it’s so obvious.

Again, most credible biologists would disagree with Behe’s premises in the above statements. There is no “strong appearance of design” and there is plenty of “compelling evidence to the contrary.” Intelligent Design is not being “overlooked…because it’s so obvious,” it is being excluded for at least four separate and important reasons: 1) the premise of absence of evidence for evolution is not valid; 2) the premise of the appearance of design is nature is not valid; 3) there is no positive evidence for the design model; 4) ID, as formulated, is not a scientific hypothesis because it is not subject to falsification. Again, ID proponents claim that it can be falsified if evolution were proven, but their threshold for “proof” of evolution is deliberately impossible.

Behe continues:

…But we can’t settle questions about reality with definitions, nor does it seem useful to search relentlessly for a non-design explanation of Mount Rushmore. Besides, whatever special restrictions scientists adopt for themselves don’t bind the public, which polls show, overwhelmingly, and sensibly, thinks that life was designed. And so do many scientists who see roles for both the messiness of evolution and the elegance of design.

Should the public dictate the validity of scientific theory over the objections of mainstream scientists? Should more polling be done to determine scientific correctness? Where would science be if it were determined by majority? This is the same majority that overwhelmingly believes that aliens are visiting the earth, that humans have the ability to communicate with their minds, and in perpetual motion machines, and that doesn’t know that the earth revolves around the sun or what the big bang is. The reality is nature is often too subtle to be discerned by the casual observations of everyday life. The naïve observations of the public cannot possibly determine that we live, for example, in a relativistic universe, or the fundamentally quantum nature of subatomic matter. Nor is it reasonable to conclude that observations made over the span of a human lifetime are up to the task of grasping natural processes that unfold over millions of years.

Behe makes an almost throwaway reference to “special restrictions scientists adopt for themselves,” belying the critical importance of this point. ID proponents desire nothing short of changing the very definition of science. They wish to include supernatural (i.e divine) causes for natural effects. They claim that scientists exclude supernatural explanations arbitrarily as part of a materialist/atheist ideology. Nothing could be further from the truth, and this claim betrays either a fundamental misunderstanding of the scientific method or profound intellectual dishonesty.

The scientific method cannot, by its very nature, include supernatural explanations. Things that are supernatural are not bound by the physical laws of nature. This renders all supernatural claims logically nonfalsifiable, and therefore incompatible with science. Scientists test hypotheses to see if they are true by carefully drawing conclusions about what the outcome of observation or experimentation should be if the hypothesis is correct or incorrect – basically by making if-then statements. For example, if humans are more closely evolutionarily related to chimpanzees than horses, then we should share more common genetic mutations with chimps than horses – even silent mutations that have no effect on development. Direct observation can test this hypothesis, and therefore evolutionary theory. However, it is not possible to ask such questions about ID, or any supernatural hypothesis, because supernatural explanations are not bound in any way – they can possess whatever features or properties are desired, without limit. What would the world look like if it were designed by a supernatural agent? Why, any possible way the designer intended.


The public debate about ID and evolution continues, with our public schools as the primary battleground. It is a battle that has been decisively won by evolution within the arena of science, but there is a perplexing and enduring disconnect between what scientists believe and what the public believes. Only improved public education about science in general and evolution in particular will close this gap, and that is exactly what Behe and other ID proponents are fighting to destroy.


1) Behe, M.J. 1996. Darwin’s Black Box: The Biochemical Challenge to Evolution. New York, N.Y.: Free Press.
2) Dictionary.Com –
3) Miller, K.R. 1996. The biochemical challenge to evolution. Accessed on 10/30/99 at
4) S.J.Gould, in “Evolution as Fact and Theory” Discover Magazine, May 1981.