I think that Edward Feser is an excellent philosopher. I also think that his criticisms of intelligent design theory are criticisms of the philosophical mistakes of ID advocates rather than criticisms of any central features of intelligent design theory. Feser criticizes intelligent design theory on a number of grounds. First, that intelligent design theory assumes a philosophy of nature that is mechanistic. Second, that intelligent design theory assumes a form of reductionism (that things are reducible to their microstructures). This criticism falls out of a mechanistic understanding of nature. Third, the designer of ID is not the Creator of classical theism, but is the designer of theistic personalism. These criticisms are quite serious but I do not believe that intelligent design theory, properly understood, is vulnerable to them.
As I have previously shown, intelligent design theory is a historical theory about how to detect the actions of intelligent agents in the past and a claim that there is evidence of intelligent action in biological systems (and possibly other natural systems). As many intelligent design advocates have stated intelligent design says nothing about the existence of God. As Feser has pointed out, it cannot say anything about God either. Intelligent design theory is not a philosophy of nature nor is a metaphysical system. It is simply a theory of historical method. One should simply accept Feser’s advice and not attempt to use intelligent design theory to arrive at the existence of God. Paley’s design arguments have no place in intelligent design theory.
The first and second criticism of Feser are much more important and much harder to deal with. Dembski does state outright that intelligent design theory studies natural things (such as cats and trees) as if they were artifacts like planes and computers. Not only this, but he proceeds as if there is no substantial difference between the two. As Feser points out, this is simply false. No natural thing is an artifact because the nature of that thing is determined by what it is rather than an external agent. So if Dembski’s understanding of intelligent design theory were true, then Feser’s criticisms of it would succeed.
It is here that we need to understand the details of the distinction between science and history. Science can, as I have noted, study the variation present within a species. If one species has the capacity to transform by variation into another species, then that is also a datum of science. Whether this has actually happened in the past, or how the present species happened to exist is a matter of history. When biologists speak of biological variation in a species and different kinds of such variation, it is often tempting to treat that as a matter of mechanism. So one might claim that sexual selection or genetic drift are simply a matter of genetic preference and chance following mathematical rules. But this is simply a matter of convenient terminology. It is natural for an intelligent design theorist to take this terminology and use it when discussing means of variation in a species. Such a theorist might claim that it is extremely improbable that any kind of natural variation will divide a species into vertebrates and invertebrates. Natural here means any natural event lacking a direct intelligent cause. They might claim that the probability is so low that believing in it is unreasonable. Nothing about this claim requires that mechanism actually be true or that things ought to be reducible to their microstructures. Yet such a claim is the essence of intelligent design theory. Therefore, intelligent design theory need not be vulnerable to Feser’s criticisms.
Demski is one of the founders of intelligent design theory and it seems that he disagrees with this. But he did set out the fundamental tenets of intelligent design theory. Mechanism was not one them. Therefore, if the fundamental tenets he set out does not require mechanism, then he is wrong to describe intelligent design theory as if it did require that. As for Feser, I do not think that he cares about intelligent design theory as long as it does not make the mistakes that he is criticizing it for making.