The primary issue at stake is the foundation of knowledge
In this cause, therefore, we ought to rest; in this cause the common sense of mankind has, in fact, rested, because it agrees with that which in all cases is the foundation of knowledge,–the undeviating course of their experience. The reasoning is the same as that by which we conclude any ancient appearances to have been the effects of volcanoes or inundations, namely, because they resemble the effects which fire and water produce before our eyes; and because we have never known these effects to result from any other operation. William Paley Natural Theology Chap. 23
Paley actually understood the epistemology of science fairly well. As he mentions there, we have to use our experience, our observations of causes, in order to understand the causes behind anciently produced phenomena. We watch what “fire” and water produce today, and if we see what seems to be the results of these particular “forces” in phenomena from the past, we ascribe “fire” and water as the causes of said phenomena.
To be sure, the context of the above quote makes it clear that he believed that design could be properly inferred to be behind the structure and function of animals in the same manner, something that even in Paley’s time strained the meaning of experience, considering how different animals are from our own designs. Nevertheless, the principle he called upon for the foundation of knowledge is sound, and not a few considered design to be a legitimate inference prior to the development of evolutionary theory. Dawkins still writes as if it would be a sound inference without Darwin’s insights and subsequent developments of theory, although I myself do not think that inferring from human design to a very different sort of “design” in life was ever as clearcut as either Paley or Dawkins consider it to be in the early nineteenth century (many ancients did not see animals mechanistically, so it appears that the industrial revolution was partly responsible for such reductionism). Let us allow that it was reasonable enough for Paley to make his arguments at that time, however.
I bring up Paley’s sound epistemology (whatever we think of his application of it) as a sort of follow-up to recent posts about Darwin’s Black Box, and equally, as a prelude to further evidences of evolution in basic biochemical pathways (whether or not Behe touches upon these). For it is one thing to claim that we do not have exact knowledge of the evolution of even something as evidently evolved as the clotting cascade, while it is quite another thing to ignore the clear evidence that it did evolve as the result of selection and also of contingency and of “accident”. Paley did not supply the exact mechanisms of design, although he typically suggests that it is quite like those of “artificers” and of “architects” (following his belief that we make proper inferences from experience). Behe not only does not provide any exact mechanisms, he seems to deliberately avoid any suggestion that the foundation of knowledge is experience, for we certainly do not experience design producing anything like the constrained and partly accidental constructions of Archaeopteryx, the clotting cascade, the systems of photosynthesis, nor an adaptive immune system built upon the innate immune system. Behe demands near-total knowledge of pathways that evolved long ago, without ever having accepted the burden to provide even a tiny level of explanation via his claims regarding “design”.
Evolutionary theory (the non-woo variety) rests upon our experience that certain physical characteristics allow animals to succeed, ultimately in the reproduction stakes, and that these physical characteristics vary from animal to animal within species, and likewise across species. More exactly in today’s understanding, evolution is recognized as being founded considerably upon the natural selection of random mutations–with both what is selected and what is “merely accidental” revealing the accidental nature of these mutations. Experience only provides us with knowledge of random mutation in nature, and of natural selection, outside of a bit of human meddling, and whatever intelligence enters into the mating strategies of the smarter animals.
So if we follow “Paley’s principle” (in reality, these could be considered to be principles of “natural philosophy” going back to Newton, and continuing through Hume, and Kant) of using experience as our guide, we can hardly suppose that the apparent duplications of genes found in the clotting cascade were caused by anything but random processes of duplication and of natural selection. What else have we ever seen producing duplication, and fixing it into genomes? Nothing, that is all.
But what of Behe’s analogies with design? Might we have we sufficient reason to suppose that cilia and the clotting cascade were in fact be designed, and thereby have at least a competing hypothesis? Hardly. Paley was quite careful to use for his examples what he understood to actually be like what human artificers and architects would produce. Behe avoids exactly such examples, because he happens to know that the most humanly design-like structures in organisms are actually quite well explained by Darwinian selection from random mutations. So from whence does he even have analogy, let alone the kind of knowledge that is firmly founded upon experience and observation?
He has none, for there is no precedent for design making the clotting cascade. And more importantly, the evidence of origination only points to causes which we know by experience are those of natural selection and random mutation. Vitamin K is crucial to the clotting cascade only because of the accident of its already existing in the organism evolving a clotting mechanism. The various proteins involved were simply co-opted and adapted because of the accident that these particular proteins already existed in the organism, apparently were duplicated (or genes were shuffled, or some other process occurred–depending on the particular protein being considered), and either had some of the needed function immediately, or did soon after a few changes occurred.
Behe actually has no evidence of design whatsoever, only his unwarranted and never substantiated belief that if evolution is not sufficient for complex articulated processes that design is responsible. Paley actually tried to make a positive case for design (he knew that it would be hypocritical to criticize the evolutionary ideas of his day for lacking proper evidence if he did not provide some for his claim), while Behe does not even make an argument in favor of design. If he and the other IDists cannot make a case for design, as they have definitely failed to do thus far, the only recourse that any real scientist has is to follow Paley’s dictum about using experience to match up known causes to known effects, and to conclude that accident and selection produced the clotting cascade that has all of the marks of random mutation, common descent, and of selection.
This is why ID is such a potential menace to science and to science education. While Paley and other proponents of natural theology prior to the development of scientific evolutionary theory were quite content to be scientific and thus to argue from cause to effect–from experience and observation to the apparently similar phenomena that happened in the past–today’s IDists pointedly bypass any rigorous match-up between the mechanisms of life and their claims of “intelligent design”. Indeed, it is in the “accidental” (in a broader sense than as used above) characters that one discerns cause, and the accidental characteristics all point to random mutation, common inheritance, and natural selection. We do not know exactly how the clotting cascade arose, but we know that we should be looking at evolution to provide the answer to that question (insofar as the question can be answered), for the only evidence of origination that we have for it points toward evolutionary. Behe’s shift to “the design provides the mutations” is as lacking in evidence (and experience) as all of his other claims, and it avoids addressing all of the random characteristics that pervade the cases which he claims could not have evolved without assistance.
The question is whether or not science is going to continue to be rigorous, and thus to apply Paley’s principle that we must use our experience as our foundation of knowledge. We say yes. The IDists say no. It does not appear as though there is any room for discussion between the “two positions,” rather the IDists would simply deny the principle by which we must gain any knowledge about the world.
This is part of a series of posts that I am combining into one long post, which may be found at Darwin’s Black Box.