ID isn't science: It's an attempt to drag religion into science

There's an old story about a scientist who spends a long time dragging a 3-inch mesh net through a lake. He looks at his catch and afterward tells everyone there are no fish smaller than three inches in the lake. His error is the same as the one David Limbaugh makes in his recent column, "Science and faith," and, ironically, the same one that is made whenever a scientist claims that science rules out the possibility of a Creator.

Limbaugh criticizes scientists ("Dyed-in-the-wool Darwinists." as he calls them) for defining science in a way that "excludes the supernatural." In fact, though, that's exactly how science must be defined.

Science is a process by which human beings try to explain events in the material world, using only the natural processes we find in the world. It has certain rules, and among them is the exclusion of appeals to the supernatural. You wouldn't really want it any other way. Do you want the physicist whose work goes into the design of an airplane to explain flight in terms of fairy dust?

At the same time, science can't disprove the supernatural. Science just has nothing to say about it. Was there an intelligent designer of the universe, or of life in the beginning, or of individual species? Maybe, but if the means used by that Designer were outside the laws of nature, then they're just not accessible to scientists. The net used by science doesn't catch anything supernatural.

Let's look at an example of how an evolutionary biologist works.

First she sees an adaptation that an organism has and asks, "How could this have evolved?" For example, consider the blood-clotting system in humans and other vertebrates. Starting from a break in a blood vessel, a series of over a dozen proteins act in a set sequence, ending with the formation of a blood clot.

The biologist has to come up with a plausible explanation (a hypothesis) of how this evolved. In this case, a hypothesis might be that this system evolved from a simpler, but still functional, system. The original system could have started with a single clotting protein. Later that protein was duplicated, and the duplicates were gradually modified by selection to work in a set order.

This hypothesis makes predictions. It says, for instance, that there were once, and maybe still are, organisms out there that use fewer blood clotting proteins than we do. It also predicts that the proteins in our clotting system should show similarities to each other.

The biologist then looks for evidence to test the hypothesis. As Kenneth Miller points out in his book "Finding Darwin's God," lobsters have a functional blood-clotting system consisting of only one protein, as predicted. Also, comparison of the proteins in our blood-clotting system shows them to be highly similar to each other in exactly the ways predicted if they were originally duplicates of one protein and then were gradually modified.

The biologist concludes that the hypothesis is supported -- that is, that the evidence agrees with the predictions, and that the hypothesis is worth keeping.

What does an "intelligent design" scientist do in this case? Well, he looks at an adaptation like the blood-clotting system, and if he can't think of a way that it evolved, then he concludes it was designed by an intelligent Creator. I'm not speculating here. This is exactly what Michael Behe, one of the ID experts cited by Limbaugh, concluded in his book, "Darwin's Black Box."

How does he test this hypothesis? What does it predict? Maybe the system should show signs of the handiwork of the Creator? What would those look like? We have no way of knowing.

If you argue that the work of the Creator will be perfect, then we can disprove that hypothesis. Ask anybody over the age of about 40 if the human knee or lower back represent engineering perfection. If the Creator's ways are unknowable, as I'd argue they are, then there are no predictions to test.

Even the one-protein system in the lobster and the similarities among our proteins don't disprove the ID hypothesis, because the Creator could have designed the system in any way the Creator wanted to, even one that looks like it evolved.

Since ID doesn't make specific predictions, it can't be tested, and therefore it's not science. This doesn't mean that it's not true, just as failing to catch fish smaller than three inches long in a net with three-inch mesh doesn't mean there aren't any smaller fish there. It just means that science is not the correct tool to use for exploring religious ideas.

To teach ID in a philosophy or religion class would be fine. To teach it in a science class is simply going to confuse kids about the nature of science.

Evolutionary biology doesn't say anything about the origins of the universe, or even of life. These are matters for physics and chemistry. It simply says that organisms on this planet are all related, that they descended from a single ancestor and that natural processes appear to be sufficient to explain how this occurred.

Contrary to Limbaugh's claim, there are, in fact, numerous examples in the scientific literature showing new species forming through natural processes, a vast amount of evidence that organisms are related to each other and well-documented examples of natural selection producing complex adaptations.

Did the Creator design the universe, and the natural processes governing it, so that this diversification and greater complexity of life would occur automatically over time, eventually leading to organisms who could discuss how the Creator did it? Maybe so. In fact, many prominent theologians think so. But that question is outside the realm of science.

Limbaugh imagines that excluding such ideas from science is the same as saying they're wrong. In fact, it's just being honest about how science works. Science is an enormously successful tool in its restricted field, but you wouldn't want to use it to choose a spouse, to compose music or to guide your faith.

ID is an attempt to drag religion into the science's net and suggest that scientific evidence has the power to answer questions about God. While teaching ID in a science class does great harm to science, it has the potential to do even greater harm to religion.

Allen Gathman is a biology professor at Southeast Missouri State University, where he teaches a course on science and religion.