The movie Expelled, released last week and featuring Ben Stein, is garnering a lot of attention for the intelligent design (ID) movement. At the core of ID seems to be the hypothesis known as irreducible complexity. Michael Behe -- professor of biochemistry at Lehigh University and a leading intelligent design advocate -- says that biological features such as the blood clotting cascade, the light sensitivity of photoreceptors in the eye, and the bacterial flagellum are examples of complex systems containing individual parts that could not function in isolation of each other.
Behe argues that the existence of irreducibly complex systems is evidence of fine-tuning by an outside agent, an "intelligent designer," who apparently is dissatisfied with the monotony of earth's life forms, and feels compelled to make inexplicable tweaks in obscure places. This designer might be a supernatural being, or it might be a space alien; the intelligent design hypothesis makes no claims about the nature of the designer.
Is intelligent design good science? Is it good theology? Based on my understanding to this point, I would have to answer no on both counts.
By setting up their hypothesis as a competitor to darwinian evolution, Behe and other ID advocates are trying to blur the line that marks the boundaries of scientific knowledge. Science is the study of the workings of the physical world. Science gives us explanations of natural phenomena. There are many areas of knowledge that are outside the scope of science: ethics, art, philosophy, and, of course, theology, to name a few. There's simply no way to squeeze God into the box of scientific inquiry.
What happens if we try to reduce the creator of the universe to a scientific hypothesis? We end up with the "god of the gaps." God is only useful when we need to explain something that we don't fully understand at the moment.
This is bad science because it can discourage further research. If we believe that increased human knowledge would decrease the power of God, we may turn a blind eye to the research into the evolution of the eye. It's bad science also because it accepts a non-conclusion as a conclusion. Merely because something is not understood scientifically does not automatically place it in the realm of external intelligent agents. There is a wide gulf between "We haven't found a natural explanation," and "We can't find a natural explanation." There is also a wide gulf between "We haven't found a natural explanation," and "An unknown intelligent being has been tinkering with life forms again." (And that's not even considering the fact that many of the "irreducibly complex systems" have been explained through natural processes, specifically through the process of exaptation. That's an issue for a separate post, which probably needs to be written by someone more able than I.)
ID is bad theology, too, as the implication of a god in the gaps theology is that God can only be seen in those things that can't be explained otherwise. So the birth of a baby, for example, could not be considered a miracle, because we understand the physical processes by which offspring are produced. But bacterial rotors... those are truly divine in origin! If intelligent design proponents took their own claims at face value, they would be followers of one strange cult.
They certainly wouldn't be followers of one Jesus of Nazareth, who said to a doubting Thomas, "You believe because you have seen my wounds," but did not add, "Blessed are those who understand the irreducible complexity of the blood clotting cascade." (Hey, that gives me an idea for my next Bible translations update...)
Anyway, thus far I've not been impressed with the intelligent design movement. Its major proponents seem to be trying to blend science with religion in a novel way, but the result is that they are making a mess of both.