We've been over this many times in the past few decades but it's still worth reminding people of the only rational response to such a claim. This is from pages 91 and 92 of Faith vs. Fact: Why Science and Religion Are Incompatible.
... some scientists persist in claiming, wrongly, that naturalism is a set-in-stone rule of science. One of these is my Ph.D. advisor, Richard Lewontin. In a review of Carl Sagan's wonderful book The Demon Haunted World, Lewontin tried to explain the methods of science:
It is not that the methods and institutions of science somehow compel us to accept material explanation of the phenomenal world, but, on the contrary, that we are forced by our a priori adherence to material causes to create an apparatus of investigation and a set of concepts that produce material explanations, no matter how counter-intuitive, no matter how mystifying to the uninitiated. Moreover, that materialism is absolute, for we cannot allow a Divine Foot in the door.That quotation has been promulgated with delight by both creationists and theologians, for it seems to show the narrow-mindedness of scientists who refuse to even admit the possibility of the supernatural and immaterial. But Lewontin was mistaken. We can in principle allow a Divine Foot in the door; it's just that we've never seen the Foot. If, for example, supernatural phenomena like healing through prayer, accurate religious prophecies, and recollection of past lives surfaced with regularity and credibility, we might be forced to abandon our adherence to purely natural explanations. And in fact we've sometimes put naturalism aside by taking some of these claims seriously and trying to study them. Examples include ESP at other "paranormal phenomena" that lack any naturalistic explanation.
Sadly, arguments similar to Lewontin's—that naturalism is a unbreakable rule of science—are echoed by scientific organizations that want to avoid alienating religious people. Liberal believers can be useful allies fighting creationism, but accommodationists fear that those believers will be driven away by any claim that science can tackle the supernatural. Better to keep comity and pretend that science by definition can say nothing about the divine. This coddling of religious sentiments was demonstrated by Eugenie Scott, the former director of an otherwise admirable anti-creationist organization, the National Center for Science Education:
First, science is a limited way of knowing, in which practitioners attempt to explain the natural world using natural explanations. By definition, science cannot consider supernatural explanations: if there is an omnipotent deity, there is no way that a scientist can exclude or include it in a research design. This is especially clear in experimental research: an omnipotent deity cannot be "controlled" (as one wag commented, "you can't put God in a test tube, or keep them out of one"). So by definition, if an individual is attempting to explain some aspect of the natural world using science, he or she must act as if there were no supernatural forces operating on it. I think this methodological naturalism is well understood by evolutionists.Note that Scott claims naturalism as part of the definition of science. But that's incorrect, for nothing in science prohibits us from considering supernatural explanations. Of course, if you define "supernatural" as "that which cannot be investigated by science," then Scott's claims become tautologically true. Otherwise, it's both glib and misleading to say that God is off-limits because he can't be "controlled" or "put in a test tube." Every study of spiritual healing or the efficacy of prayer (which, if done properly, includes controls) puts God into a test tube. It's the same for tests of non-divine supernatural phenomena like ESP, ghosts, and out-of-body experiences. If something is supposed to exist in a way that has tangible effects of the universe, it falls within the ambit of science. And supernatural beings and phenomena can have real-world effects.