Thanks to Olegt, I can now refer readers to what I consider to be an excellent essay by Michael Behe, at the same place that Stephen Barr published his.
Some of my favorite passages:
… Reading the old Encyclopedia entry reminded me of G.K. Chesterton's observations in Orthodoxy that “The Christian is quite free to believe that there is a considerable amount of settled order and inevitable development in the universe. But the materialist is not allowed to admit into his spotless machine the slightest speck of spiritualism or miracle.” Unlike materialists, Christians can serenely evaluate the physical evidence. If the universe unfolded completely through the regularities of God's laws, fine. If it unfolded mostly by law but also by irregularities or special actions of some sort, that's fine too.
Unfortunately, there's a large obstacle in the path of Christians who want to exercise their freedom to follow the evidence wherever it leads. Christians may have more freedom than materialists in deciding on the best explanation for nature, but overwhelmingly it is materialists—or practical materialists—who tell Christians the story of nature. So information about the way the universe works almost invariably passes through a rigid materialistic filter before it reaches the general public. …
As a postdoctoral associate at the National Institutes of Health in the early 1980s, I shared a lab with a woman named Joanne, a fellow postdoc and a serious Catholic. One slow afternoon she and I were gabbing about the Big Questions, including the origin of life. “What would be needed to get the first cell?” she asked. “You'd need a membrane for sure,” I said. “And metabolism.” “Can't do without a genetic code,” she added, “and proteins.” We stopped, stared at each other, and both shouted, “Naaaaahh!” Then we laughed and got back to work. Even though we quickly realized that there were brick walls everywhere one looked, our only reaction was to chuckle. What we didn't do was to question seriously whether the unfolding of physical laws could adequately explain the very start of life. I guess we vaguely thought that even if we didn't know, somebody else must. Or, even if no one knew, somebody would figure it out soon. Or eventually. There we were, two young, well-educated Catholic scientists, as free as the wind to come to our own conclusions, and we punted.
I hate to imagine what Chesterton would say about such fine specimens of free Christian thinking as Joanne and me. Yet a practical problem arises from a Christian's freedom to find “a considerable amount of settled order and inevitable development” in nature: In a scientific culture dominated by materialism, social pressure will push Christians to concede whatever is possible to concede as “inevitable.” At first, the concession might simply be irenic, to avoid conflict with materialists in areas that are cloudy and are thought to be unimportant. But as science progresses and claims more questions as legitimate fields of inquiry, the habit of not making waves can become dangerous, as the precedent of conceding the interpretation of material reality to materialists becomes firmly established. In the end, the ability of a Christian to see the hand of God in nature—not in some gauzy, emotional sense, but as a deduction from the physical data—is finally considered illegitimate. One day it was just the evolution of species that was unapproachable. The next day, the origin of life and the universe. Today even the origin of the mind falls under the materialist program.