There was a period in the Dark Ages when the "scholastics," the best thinkers of their time, studied the world not by observing the universe around them, but by dissecting the thoughts of the ancient Greek Aristotle. Today the proponents of "intelligent design," or ID, are going beyond even the old scholastics in intellectual perversity.
If that seems like a strong statement, consider the central logic of ID:
- Point A. There are many things about biology and the origin of life for which evolution has no explanation.
- Point B. Therefore these things cannot possibly be explained, and some better explanation must be brought forth.
- Point C. Since they cannot be explained, they have necessarily been designed.
- Point D. That statement having been made, evolutionary theory is crippled and must be supplemented by ID.
Every application of ID has this cracked logical structure, although it's commonly hidden with rhetorical sleight-of-hand. For a simple example look at an article by leading ID figure Michael Behe, "Molecular Machines: Experimental Support for the Design Inference." You can read it all for yourself, but let me bring out the four perverse points of the ID argument. He begins with a familiar problem in biology, the history and mechanism of vision.
Point A: Never Mind What Darwin Said
- A. When Darwin discussed the evolution of eyes, he ignored the underlying mechanism that turns light into nerve impulses, saying "How a nerve comes to be sensitive to light hardly concerns us more than how life itself originated." But that underlying mechanism is now becoming well known. (Here Behe details the complicated rhodopsin cycle that underlies human vision.) To successfully explain life, we must now explain it in atomic detail. "Anatomy is, quite simply, irrelevant. So is the fossil record. It does not matter whether or not the fossil record is consistent with evolutionary theory, any more than it mattered in physics that Newton's theory was consistent with everyday experience."
Behe asserts point A by changing the subject from evolution of eyes to the molecular mechanics of vision, an area where science is merely compiling facts without reference to evolutionary theory. He pretends to declare Darwin's evidence dead, but having left the field of organisms and species, where evolution applies, Behe has made an empty statement. Where Einstein deepened Newton's vision, Behe has deserted Darwin's.
Point B: I Can't Explain It, So No One Can
- B. The mechanism of vision is an instance of "irreducible complexity," which Behe defines as "a single system which is composed of several interacting parts that contribute to the basic function, and where the removal of any one of the parts causes the system to effectively cease functioning. An irreducibly complex system cannot be produced gradually by slight, successive modifications of a precursor system, since any precursor to an irreducibly complex system is by definition nonfunctional." (His first example is the mousetrap, which of course has no evolutionary explanation.)
Behe asserts point B with the axiomatic declaration that complexity cannot arise from simplicity; he won't allow such explanations even to be imagined, let alone tested. Logicians will easily recognize that Behe's axiom rules out everything except miracles. His "irreducible complexity" is a corrupt idea, invalid from birth.
Point C: Quod Erat Obfuscandum
- C. There are many "irreducible systems." Consider the cilium, the tiny whiplike propellor that certain microbes and cells use. Because it is "irreducible," evolution cannot have produced it. Therefore, like the mousetrap, it was designed.
Point D: Everything They Know Is Wrong
- D. Evolution is obviously broken; look at the contents of the leading journals. None of them are publishing papers about how complex biochemical systems like rhodopsin or cilia arise from precursors. Only by admitting design can we make further progress.
Behe does not realize that his field is in the same state geology was in during Darwin's time. Geology was in the midst of observing and describing the world's lands, rocks and fossils, building a huge body of information from the ground up. It took another century for a geological theory to ariseplate tectonicswith a scope comparable to evolution. Before then was mostly arm-waving, and geologists have learned to be modest in their theorizing ever since. We may wait a hundred years after Michael Behe is gone for a similar theoretical edifice in molecular biology. Under "intelligent design," that time would last longer than the Dark Ages.