One of my guilty pleasures is reading Uncommon Descent (UD), the Intelligent Design blog started by William Dembski, and now mainly written by some of the lesser lights of the ID crowd. Now, ID is fundamentally of course an attempt to insert Creationism into science, without mentioning that the designer is the Christian god.
One of the sub-plots in ID is the attack on materialism as a foundation for science. This is the text of the About page on UD:
Materialistic ideology has subverted the study of biological and cosmological origins so that the actual content of these sciences has become corrupted. The problem, therefore, is not merely that science is being used illegitimately to promote a materialistic worldview, but that this worldview is actively undermining scientific inquiry, leading to incorrect and unsupported conclusions about biological and cosmological origins. At the same time, intelligent design (ID) offers a promising scientific alternative to materialistic theories of biological and cosmological evolution — an alternative that is finding increasing theoretical and empirical support. Hence, ID needs to be vigorously developed as a scientific, intellectual, and cultural project. (emphasis added)
Bear in mind that IDists will tell you that ID postits there is a designer, but says nothing about the nature of that designer. So it doesn't insist on the designer being none-material.
Yesterday in a comment thread over at UD, StephenB asked a critical question:
—Drew Mazanec: “If for the sake of argument, metaphysical naturalism were disproven, would you be willing to rethink whether or not science should hold to methodological naturalism.”
Were you under the mistaken impression that ID embraces methodological naturalism?
To which I would answer (were I not banninated) "from reading the ID literature". It's ironic that whenever ID tries to do science, it uses methodological naturalism.
You want me to back up a moment, don't you?
OK, let's answer the question you're asking: what's methodological naturalism? For starters, naturalism (be careful not to confuse it with naturism) is the idea that we can explain everything with natural forces. No need to introduce gods, faeries or flying spaghetti monsters into the explanation. There are two flavours of this. Philosophical naturalism says that material explanation is all there is: there is no non-material world. Methodological naturalism is a weaker stance: it says that if we are to learn about the real world, then we have to assume naturalism. This stance can be taken by Christian who are also scientists: they believe in a material god, but try to explain the world they are investigating without positing his direct action.
OK, back to ID. Let's take one example of ID trying to do science: Dembski's Explanatory Filter. With this one calculates the CSI ("Complex Specified Information") of an object. If this is low, then one concludes it was produced by Law-like behaviour, if it's fairly high then chance could be involved, and if it's really high then it has to have come about by intelligent design.
The key thing here is that CSI is calculated as the probability that the object would come together in that structure by chance, i.e. by natural processes. and the explanatory filter works by asking whether different natural processes could have created the pattern. It never formally tests the design hypothesis, except by trying to eliminate everything else. So Dembski's Explanatory filter works by assuming methodological naturalism!
The same thing happens whenever an IDist tries to do science: be he Behe and his irreducible complexity, or Dembski and Marks with their Active Information. I think this is telling: if they are to make any progress with ID, they need to investigate the real world. If they posit a designer, but say nothing about how that designer operates, then they cannot use the designer in their model of their data. Hence they have to assume natural processes. If they put the designer in they have to make some assumptions about that designer's abilities, an approach they reject a priori.