The Debate Between Evolution and Intelligent Design Rick Garlikov

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1 The Debate Between Evolution and Intelligent Design Rick Garlikov Handled intelligently and reasonably, the debate between evolution (the theory that life evolved by random mutation and natural selection) and intelligent design (the view that life is the product of intelligent plan by a higher being or designer) could be an exciting catalyst for students to learn how science works and what its limitations are. But, sadly, schools typically do not teach subjects intelligently and reasonably. So the subject is culturally divisive rather than educationally and intellectually useful. This is particularly sad because some of the best of what can be said on both sides was written clearly and beautifully more than 200 years ago and could easily serve as the foundation for teaching about the nature of science, the nature of rationality, and the nature of thought. First, I am not talking about the Biblical account of creation as a literal guide, because that does not square with the abundant empirical evidence we have about the origin of life and the universe. Anyone who would choose to believe literally the Biblical story of creation over the empirical geologic, chemical, physical, biochemical, and biological evidence of the nature of evolution is free to do so in a democracy, just as one is free to ignore evidence about anything in life. But being free to be ignorant and irrational, even in groups, does not make one knowledgeable and rational. Many people who claim that the theory of evolution is stupid do not even know what the theory is. They falsely characterize it as the view that fish grew lungs and legs, and man comes from monkeys. There is no reason to debate people who hold this view, because they are not interested in looking at evidence in a reasonable way. They are only interested in maintaining their conclusion without letting any facts intrude. Many scientists and science teachers, however, take unnecessary umbrage at the labeling of evolution as a theory instead of as a fact, as though theories in science are not well-confirmed, and as if there were no difference between confirmed theories and wild conjectures. Evolution is a well-confirmed theory, but confirmed theories are nevertheless not facts. And the theory of evolution, no matter how well-confirmed, does not yet fully explain in a satisfactory way the origin of complex life, such as human beings with complex systems, organs, and properties. But the fact that it is a theory and yet not a complete theory does not diminish its value, for it still explains a lot. The more interesting and useful debate between intelligent design and evolution is one that predates Darwin s Origin of the Species by more than 50 years, and recently has taken a more sophisticated biochemical turn. Yet even that debate fosters a false dichotomy, seeming to demand a choice between two options which are not necessarily mutually exclusive nor even exhaustive of the possibilities. The specific argument from design I have in mind shows a major hole in the theory of evolution that needs to be accounted for scientifically (empirically) if possible. That argument from design, however, jumps to a faulty or hasty conclusion about the significance of the problem for science. It merely points out a scientific problem about evolution that is yet to be solved. It is not a catastrophe for or disconfirmation of the theory. 1/5

2 Then finally, there is a much deeper philosophical problem behind all this, which is the question of what counts as an explanation, or a satisfying explanation in the first place, because it may be that even science does not really give explanations, but only shows patterns that give certain results, some of which seem to be satisfying psychologically and some of which do not. When I was a child, an uncle showed me a magic trick making a toy car move by waving his hand over it without touching it. I asked how he did it, and he showed me a magnet in his hand. I had never heard of a magnet before, and I did not understand how the magnet made the car move. So I didn t understand how the magnet made the car move any more than how his hand made the car move. He couldn t answer that, and I am not sure that anyone can. We know in some sense how magnetism works but not why it works. We just know that nature works in certain ways, but we do not really get to find out why. We can sometimes find mechanisms or patterns that psychologically satisfy our curiosity at least temporarily, but one could always ask why the mechanisms work as they do to give the results they do, and what causes the patterns to be the way they are. It is just that sometimes we do not ask any further because we are somehow psychologically satisfied by what we observe. But what makes for a satisfying answer is itself an interesting question. To take just one example, it does not make us curious that liquids and gases can mix but solids cannot, even though solids have plenty of empty space between the parts of their atoms. Why can t solids mix in the same way liquids or gases do? Why can t we pass through walls in the same way we pass through air? Or to take another example, science books say we can increase an object s potential energy by raising it higher above the ground, thus adding potential energy to it hence if it falls, it hits harder. But we can also increase the potential energy of an object by digging a hole under what it sits on. But it ought to seem odd that we can add energy to an object without doing anything to it, but instead by doing something to the ground under it. Therefore the concept of potential energy ought itself to seem odd. In 1802, more than 50 years before the publication of Darwin's Origin of the Species, William Paley published Evidence of the Existence and Attributes of the Deity. In that insightful book, he had a most ingenious argument against evolution as a complete explanation of the origin of life -- an argument that is still relevant today, particularly when put in biochemical terms at the molecular and genetic level. Specifically what Paley argued was that if we found a watch out in the middle of nowhere, we would postulate that someone designed and made it even if it did not keep perfect time, even if it did not work at all, even if we found that it could reproduce other watches (and thus might itself have been made by a prior watch thus shifting our question to what made the first watch, rather than perhaps the particular one we had found). He argues that the human eye is far more sophisticated in many ways than a watch, and therefore it would be absurd to argue that the watch must have been designed but that the eye could have just come about by some sort of random chance, even in combination with some kind of theory of evolution the idea of which preceded Darwin. We would never say the watch might have just evolved out there in the woods or the desert or the bottom of the ocean. Why should we take the watch as evidence of design, but not the human eye? 2/5

3 Darwin pointed out and demonstrated, what is reasonable and observable, that mutations occur in species, some of which give rise to new species or new varieties within a species. When, under given environmental conditions, those mutations are not fatal to the new variety or species before it can reproduce, it will survive and perpetuate. When the mutations are helpful for survival and/or propagation under some given environmental conditions, the species will even flourish. Biology books give many examples of how this has been seen to work. What is not answered, nor necessarily even addressed by the theory of evolution itself, is how or why extremely complex mutations arise that can be of benefit. I think it was Bertrand Russell, certainly no champion of religion, who said something like the odds that a complex organism could benefit from a random mutation is similar to the odds that efficiency of a grandfather clock might be improved by shooting a bullet into it. The question is how in an intricate organism beneficial complex molecules arise from seemingly random mutations. But simply asking the question of how complex mutations can arise and be beneficial, and then postulating a designer, avoids the question rather than answering it. There may be a natural or scientific explanation. As an illustration of the problem, at the biochemical level, we could look at the hemoglobin molecule, among a multitude of other molecules and processes, which is very intricate in how it works, based in part on its complex structure. But hemoglobin molecules did not just spring up whole cloth from one mutation, and they would be of no use if they did arise unless there was blood and a system of oxygenating it and transporting the oxygenated hemoglobin molecules to where the oxygen could be unloaded and utilized. Perhaps we have millions of molecules in our bodies that have yet to develop into something else that will serve a useful function, but it seems odd to think that partially developed hemoglobin molecules came about and just hung around until one or six more mutations made them useful. When we look at the intricacy of any of a large number of molecules and processes in the human body, and even in many lower organisms, their existence is not explained satisfactory just by the notion of spontaneous mutation. Many of them take many mutations to arise at all, and far more other mutations and structures to arise in order to let them have a useful role or function. But just because something has a use does not mean it was designed for that purpose (books can be used as door stops, but they were not designed for that purpose; and we might plant a tree for fruit or for shade without intending to kill the grass in its shade, even though that might be the result). But when something extremely complex turns out to have a crucial function in an even more complex organism, it seems, as Paley pointed out, too incredible to just have come about by chance. What we want to know is what the mechanism is that brought it all about and assembled it all in the right system at the right time. We can accept that random mutations occur. But random mutations seem hardly likely to have produced hemoglobin molecules in beings with lungs and a blood stream. Of course mutations that are beneficial for the survival and reproductive benefit of a species will help it flourish, but that does not explain how complex mutations come about at just the right place and time in order to serve a beneficial and crucial function. We need a mechanism in nature in chemistry or physics that accounts for the rise of complex molecules that can have a 3/5

4 beneficial function even if they were not designed for a particular purpose by a designer. Without such an explanation, evolution and natural selection just by themselves do not satisfactorily account for the origin of human life in the complex way it works, particularly at the biochemical level. What is missing the problem pointed out by Paley is just as important as what we know. We know that mutations come about and serve with natural selection to explain the rise and demise or flourishing of a species. But while it is easy to see how harmful mutations can arise since any bullet to a complex mechanism is likely to be harmful, the origin of multiple, jointly necessary, complex, functionally useful and beneficial mutations at all is still an enigma that needs explanation. In short, as Paley's arguments from design persuasively demonstrate, evolution does not explain or answer the most interesting questions about the origin of human life. And though the theory from design points that out, its explanation is not satisfying either, for even if it were true that design plays some part, we would want to know how the process works to bring that design into effect. The process is a scientific or empirical and philosophical question, whether there is intelligent design at work ultimately or not. The really interesting scientific question about all this, whether there is design or not, is how complex beneficial mutations arise. What is the mechanism or mechanisms that produce them? For it seems there must be more to it than just random chance or random mutation. And in terms of Paley's argument, even if we found a watch in the middle of the woods, and even if we had never seen such an instrument before and were led immediately to believe that it obviously must have been designed, many of us would still want to know how it works. We would examine it, probably take it apart, think about it, test it or perhaps a similar design of our own. We would not be satisfied to say that we found this marvelous, complex thing in the woods that could keep time and/or reproduce other instruments just like itself, etc. and that it must have been designed and manufactured. We would want to know how it worked and how it was made. We might want to know how the designer figured out to make it in the first place, and how s/he figured out the design and the manufacturing process. Believing there is a designer of the watch (or the eye, or the hemoglobin molecule) does not preclude the scientific exploration or explanations of how these thing work or how they were made. We would not be content just with the "explanation" that the designer "commanded it into existence" and that there is no other process that constructed it or that constructed any part of the mechanism that allows it to work. Those who are content not to wonder how it works or how it was made are simply those who have no (scientific) curiosity about such things. For the sake of completeness, let me mention one other work, one that predates Paley. David Hume s posthumous work Dialogues Concerning Natural Religion, published in 1779, shows problems with design as the explanation of life, even given the problems with the explanation based on evolution. For the philosophically curious, Hume s book is still one of the best and most intellectually exciting works to read today. It is too good to do justice by abbreviation, so I will not go into its specifics here, but only mention it because it is relevant and fascinating. Natural religion or religion based on observations of nature is the study of what, if anything, we might know about God from what we can observe in nature. Natural religion is unrelated to revealed religion (such as the Bible), and it relies upon what today would be considered 4/5

5 scientific observation as its data about which to reflect and make deductions. Natural religion uses science instead of conflicting with it; but it goes on to make deductions that may be logically meaningful or suggestive even if not empirically (i.e., scientifically) verifiable. Natural religion is sometimes the grounds on which a scientist, knowledgeable about how intricate some phenomena in the universe really are, bases his or her belief in a supreme being, because no other potential explanation seems that it could account for such intricacy. Hume's work responds to that challenge and makes the problem and the issues even more interesting. These are all fascinating issues that should be alive in schools because they are part of our intellectual and cultural heritage and because many students otherwise bored with science and with school as it is taught today would find them stimulating and challenging. It would lead many students into an interest in science, psychology, and philosophy who will otherwise never even know about them. But to do this it has to be taught with sensitivity and understanding. And those are rare commodities today in the cultural divide. 5/5