Tuesday, December 20, 2005

Intelligent Design in the Science Classroom

There are several court cases and school board elections in the United States revolving around the issue of the teaching, or even the mere mention, of Intelligent Design in science classrooms. ID is, basically, the idea that the complexity of the world around us shows the influence of an architect; in essence, a divine creator. An example that usually arises is the claim that the human eye could not have evolved because there are too many steps between non-eye and eye. Evolution, supposedly, is sequential, and the fact that a partial eye confers no reproductive advantage, the theory of evolution fails to explain the development of the eye. Only an intelligent designer able to conceive of and construct the entire eye could have brought about the presence of eyes in humans (and other animals.) He did this instantly…no half-measures.

Proponents claim that ID is every much a science as is evolution. At least, ID is no more a religion than is evolution. Therefore, ID should be taught in science class. At a minimum, a statement should be read to science students that the theory of evolution is found wanting in some areas, and Intelligent Design provides the answers.

As a retired science teacher, I find myself in an ironic position. I agree whole-heartedly that ID, or even the statement requested by ID fans, has no place in a science classroom. Yet I discussed ID in my classroom, of my own volition. The difference was, I discussed why ID was out of the realm of science, without actually declaring its truth or falsity.

A recurring theme in my senior physics course was the distinction between religion/belief/philosophy and science. With examples drawn from ancient Greece, from the European eras Galileo, Newton, Darwin, and Einstein, and from twentieth century America, I tried to show how the disciplines differed.

Science deals with observable, repeatable phenomena and provides testable, falsifiable explanations. By definition, an explanation for a specific phenomenon or observation that includes God would not be a valid scientific explanation.

The reason is simple: since God can do anything he wants (or she wants, but we’ll stick with “he” for simplicity) he could make the phenomenon happen or not happen on a whim. Repeatability goes out the window. Similarly, you can’t test for God. To be contrary, suppose that a test does exist for the presence of God. For argument’s sake, we can suppose the test to be the mixing of two liquids, with favourable results being a yellow product. That is, suppose that if we mix the two liquids and get a yellow product, that means God exists. We demonstrate, repeatedly, the positive result: yellow after yellow after yellow. Each time we mix the liquids, the product turns yellow. We say, “See, God exists.” Suddenly, one day, the result is red. What do we say then when we see a result that is contrary to known behaviour of the two liquids? It would be like seeing a falling ball suddenly hovering motionless in the air. We’d call that a miracle (if we had no other physical explanation, such as hidden strings or magnets). But consider: a miracle is evidence of God’s existence. So if the liquids turned yellow or didn’t turn yellow, both results supposedly implied that God exists. Thus the experiment was irrelevant. There can be no test for God.

I tell my students, “I’m not saying that God doesn’t exist, only that there is no scientific test that can confirm it.” The statement “God exists” is philosophical, religious, a statement of belief.

In science, no acceptable explanations for an event can mention God. How did the Grand Canyon form? Explanation: God made it. How was Earth created? God made it. How does haemoglobin carry oxygen? God puts it there. These explanations may be true (who knows?) but are simply not scientific.

A God explanation is an intellectual dead-end for a scientist. And for you, too. Have you watched magic shows? The magician makes a rabbit appear from an empty black hat. Don’t you think to yourself, “How did he do it?” The very act of searching for an explanation shows that you believe that the magician was subject to the same laws of physics as you are, and used no true magic. How disappointing magic shows would be if the true explanation for each trick was “magic”! You might as well not try to figure anything out, if the explanation is “magic”.

Science, the search for physical explanations, deals only with non-God hypotheses. That’s why Intelligent Design is an unacceptable scientific explanation for a phenomenon.

Intelligent Design grew out of (evolved!) from Creation Science. Most creationists were fundamentalists, believers in the literal interpretation of the Bible. They taught that God made the world as described in Genesis, fundamentally as we see it today. He made the mountains, the valleys, the plants, the animals, and the humans. There was no evolution; the Earth was young. Creation Science’s close adherence to the Bible made the religious connection obvious. The US Supreme Court ruled that Creation “Science” could not be taught as a science.

The Intelligent Design proponents try to escape the “religion” label. They say that they are not discussing religion in the classroom (which would be contrary to the US Constitution.) Rather, they are proposing a valid “scientific” explanation for a phenomenon that happens to involve an architect. The distinction between the architect and God is rather tenuous. (And arguing that there is such a distinction is somewhat disingenuous.)

ID looked good at first blush, but fails on a number of planes. As already mentioned, ID requires a deity. But let’s ignore that fatal wound for a minute. ID fails for other reasons. The sequential evolution of the eye can be shown to provide benefits during the intermediate steps. As explained in Dawson’s book The Blind Clockmaker, there are animals on Earth right now possessing “eyes” (or light detecting regions/organs) in a multitude of different shapes and complexities that can be strung together to demonstrate the development of the human eye (or follow alternate paths for the evolution of other eyes, such as that of the octopus or house fly.) The presence of each “partial-eye” is advantageous over the previous step. Second, our eyes, although very good, could have been designed better. The light-sensing cells of the retina are backward, with nerve connections to the brain extending toward the front (i.e. inside the eye) rather than the back. The result is less than optimum light reception, and a blind spot where the bundled nerves pass through the retina on the way to the brain. The “Intelligent” designer was not fully intelligent in the case of the human eye. (Evolution, however, just goes where it goes. The drift is toward improvement, but optimal results are not guaranteed.)

There are many examples where an intelligent designer could have done a better job. Here’s another. Unlike women’s ovaries, men’s testicles hang outside the body, exposing them to potential harm. The reason is that sperm must be formed and stored at below body temperature. Why not just make sperm that “liked” body temperature? Remember, the designer had God-like powers, and God can do anything. He certainly could have made sperm that thrived at 37°C.

At this point, many IDers will say that God must have had some other reason for making eyes or testicles in what appears to be a less efficient manor. This is the old “God moves in mysterious ways” argument. The problem with this damage control spin is a little abstract. “God moves in mysterious ways” makes the original claim of God’s intervention non-falsifiable. Here’s why: when we see an example of something that works as we expect a God would have make it, we say “Look. There’s good evidence for our (God) argument.” When we see something that runs counter to the God-did-it argument, we say “Well, it probably supports the argument too, but we just can’t see the connection.” Thus the God-did-it argument holds regardless of whether we perceive it or not. Evidence is irrelevant.

At a little deeper level, the “mysterious ways” argument is intellectually dishonest. When we announce a connection between the world and what we feel God would have done, we are claiming that humans have the ability to grasp the divine purpose. But when we retreat to “God moves in mysterious ways” we are saying that humans don’t have the ability to grasp the divine purpose. You can’t have it both ways.

I taught all the above, little by little when applicable, to my senior science students. When someone asked “Do you believe in God?” I refused to answer yes or no. My response was that I did not want to influence young person toward either answer. When a student asked “Do you believe in evolution?” my response was, “By using the word “believe” you are asking for my religious position." If the student rephrased the question as "Do you think evolution is a good scientific explanation for the living world as we see it?” my response was, "Yes. Evidence for evolution is wide-spread and overwhelming."

If you ask, “Should science teachers be forced to mention Intelligent Design in their classrooms” my response is “No.” And, if you ask, “Did I mention ID in my classes?” my answer is “Yes”.

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