I’m currently involved in a discussion on the Uncommon Descent blog, and while my post there awaits moderation, I thought I’d share it here.
Since those in the natural sciences would generally not consider my field a science (except perhaps in Germany, where it is all Wissenschaft), I won’t get entangled in a debate about the definition of science. [In my religion and science class today we discussed Schafersman's famous piece on the subject, and found it helpful but also problematic]. But in terms of whether or not Darwinian evolution follows a valid and logical reasoning, it seems to me to be no more problematic than linguistics, which cannot watch Latin evolve into the modern Romance languages (much less Indo-European into Sanskrit, Latin, etc), surely the ways languages splinter and develop today, plus the ‘fossils’ we have in texts, make the theory of linguistic evolution as certain as anything one might claim about the past. As someone who believes that criminals are rightly convicted on the basis of forensic evidence plus deductive reasoning even when no one saw them do it, I find unpersuasive the argument that evolution is a problematic theory because it is supposedly untestable or unrepeatable. [The comparison with linguistics is indebted of course to Robert Pennock's book Tower of Babel, reviews of which can be found here, here, here and here]
Of course, if one focuses solely on natural selection, one will of course find it unsatisfactory. One had to include other factors entirely, such as sexual selection, to account for the peacock’s impressive feathers, which are presumably advantageous enough in impressing peahens that the disadvantages they must offer when it comes to quickly escaping predators and that sort of thing.
I am willing to grant that for at least a small number of individuals, ID and CS are distinct. For many who use the terms, however, the distinction is at best unclear – e.g. the creators of the board game ‘Intelligent Design vs. Evolution’!
The main reason I find myself unpersuaded by ID as a scientific approach is that it wishes to redefine science rather than play according to its rules. I do not believe science requires adherence to metaphysical naturalism, but I do think it requires methodological naturalism, because science itself is about natural processes. If any agent (whether a human being, God, angels or fairies) goes into a scientist’s lab late at night and tinkers with the knobs and stirs in the beakers, the experiment will be invalidated. That doesn’t mean persons natural or supernatural don’t have a role to play in the universe – it just means that science isn’t about that, at least as the overwhelming majority of scientists understand it.
ID may be based on observation, but so was Paley’s design argument. Shifting the locus of design back from the macro to the micro/biochemical level doesn’t change the fact that the argument seemed persuasive but turned out to be problematic, and allying oneself to the argument then as now provides ammunition to the opponents of faith, rather than helping its cause.