Robert T. Miller replies to my letter in First Things with a number of arguments which, in my opinion, fall short. His response appears in block quotes below and my replies follow:
Richard L. Cleary runs together several things that ought to be kept separate. Multiverses, strings, and multiple dimensions are unobservable entities posited to explain observed phenomena, such entities are no less scientific posits than subatomic particles or gravitational fields, which are equally unobservable.
A designer is also an unobservable entity posited to explain observed phenomena. In this it is analogous to multiverses, etc. To state that other worlds, strings, and so on are "no less scientific posits" as particles and fields is simply false. Particles and fields are detectable and measurable, which is why they are part of empirical science. Other worlds, dimensions, etc., like a designer, are not measurable, or at least at present we know of no way to quantify them.
Discussions of the scientific method or standards of scientific reasoning, while not scientific posits, are properly part of science education, which not only conveys scientific knowledge but teaches the methods and principles by which such knowledge is gained.
In other words, the undergirding philosophical principles of science, i.e. the content of the discipline of the philosophy of science, is a legitimate topic for science education. Intelligent Design is, at least, a philosophical hypothesis with implications for the work of science. Why then should it not be a suitable topic for a science classroom? Mr. Miller offers an answer:
The philosophy of science by contrast, is a subdivision of philosophy that treats philosophical questions arising from science, like whether scientific laws are mere regularities or metaphysically necessary truths.
This is incorrect. The questions he mentions comprise only part of the philosophy of science. Discussions of the methods and standards scientists observe and practice are also part of the philosophy of science and Miller is making an illicit distinction here by trying to separate them. The point is that science is often, in practice, inseparable from the philosophy of science. Mr. Miller wants to exclude the latter from the teaching of the former in order to quarantine ID, but what he's proposing is heuristically undesirable. It would reduce science instruction to the sheer presentation of facts and eviscerate it of everything that gives it life and fascination.
All of these are different from Intelligent Design, which is a philosophical theory in direct competition with a scientific theory.
This is also incorrect. ID is in conflict or competition with no scientific theory. It is in direct competition, rather, with the metaphysical claim that the cosmos and life are exhaustively and plausibly explicable, in principle, solely by reference to physical forces and processes. If Mr. Miller thinks that this claim is a scientific assertion then I would ask him to explain how it can be tested. Furthermore, even were he correct that it is a scientific assertion he would be in the awkward position of assigning the claim scientific status while arguing that the denial of the claim is philosophical.
As a I have already said, as a matter of policy, we ought not to teach philosophical theories in science classes; as a matter of constitutional law, if for religious purposes we teach nonscientific theories in public schools, or even scientific theories not accepted in the scientific community, we also violate the establishment clause.
What Mr. Miller does not seem to realize is that everything a Christian does is done for religious purposes. For the Christian there is no sacred/secular dichotomy. All of life is lived in service to God. What is "secular" is whatever the Christian happens to do that non-Christians also do. Christian school board members who serve their school district do so because they believe that they are thereby serving God. Mr. Miller's interpretation of the establishment clause would constitutionally exclude Christians from making curriculum decisions, or, indeed, any decisions about the governance of a school. It would indeed, followed to its logical conclusion, exclude Christians from serving on school boards altogether.
Moreover, if Mr. Miller's interpretation of the First Amendment is correct why does it apply only to theists? After all, many atheists have a religious motivation for demanding that only materialist explanations be taught in schools. Mr. Miller seems willing to allow the atheist's religious motivation while excluding the motivations of those who might wish to avoid giving Christian students the impression that their school's teachers reject some of their basic beliefs about the world. Is that what the framers of the constitution intended?