BARNES'     CHAPTER FOUR: THE EVOLUTION OF LIFE
[ © 2005 by Michael H. Barnes; all rights reserved]

BACKGROUND TO DARWINIAN THEORY

Darwin's theory of biological evolution was developed against the background of general notions of the evolution of the entire universe. The philosopher Descartes, for example, had explored the idea of cosmic evolution in his Principle of Philosophy in the early 17th century, though he concluded that any cosmic process of change had to proceed mechanically up to the present stable order of things, now no longer evolving. Immanuel Kant had gone further, offering more arguments and extending his speculation into rather wild realms of thought for the time in his Universal Natural History and Theory of the Heavens in 1755. LaPlace's late 18th century work, mentioned briefly earlier, was a continuation of this line.

Others began to find evidence to justify evolutionary theories about the geological layers of the earth. The geologists of the 18th and earliest 19th centuries mostly resisted theories of a long period of geological evolution. They were people raised to accept the bible and the traditional interpretation that God had created the world much as it is now. They could account for many strange formations on earth by supposing that there had been catastrophes in the past, including those caused by God as in the great flood in the time of Noah (that was how all those seashells got to the mountain tops!). This way of interpreting the earth's history was known as "catastrophism." These traditional geologists believed that the biblical account of the history of the whole world was at least approximately correct, so that the estimate made by an Anglican bishop that the earth was created in 4004 B.C. was plausible to them.

The idea that the earth itself, however, had also undergone a very long process of change, a kind of geological evolution, was compatible with a number of ideas and evidence. It was an idea that could make sense of all sorts of evidence, from sea shells on mountaintops, to the layering of rock as seen in ditches and mines and on mountainsides and along oceans, as well as the layering of different kinds of fossils in those strata of rock, to the remnants left behind in various layers along the paths of glaciers, to observation of present day erosion and the laying down of sediment and the activity of volcanoes, and so forth.

By 1795 James Hutton was able to assemble a vast range of data in favor of "uniformitarianism" (though he did not use that word). This was the theory that the current condition of the earth was not the result of a few past catastrophes like Noah's flood wreaked upon God's basically unchanging and relatively recent creation. It was instead the product of long uniform processes of the same kind that were still occurring, to build up mountains and erode them down again, to lay down silt deposits until their weight melted the bottom layer and produced rock, and so forth. Hutton is thereby credited with the discovery of “deep time.” Hutton thought, however, that God has made the earth go through these long processes as a way of keeping the surface fresh and useful for human habitation. (I have no idea how he explained earthquakes.) Charles Lyell (1797-1875) confirmed Hutton's uniformitarianism with his 3 volume (1830-1833) Principles of Geology, read by Charles Darwin aboard the Beagle.

Both “catastrophism” and uniformitarianism” are misleading names today. Geologists think that the history of the earth is the product of uniform laws of nature which produce endless catastrophies such as volcanic eruptions and earthquakes. The main issues for religion and science are whether the processes of the past are due to natural causes without any divine interventions, and whether this whole process looks so unplanned as to make the idea of a Designer implausible.

In the 18th century there were new theories of the evolution of culture also. The voyages to strange lands and peoples that had been going on since the end of the fifteenth century had brought a confusion of information about tribal life. The discovery of the new world and its inhabitants evoked worried discussions about human nature. As long as Europeans had contact mainly with complex literate civilizations like Islam or had knowledge of major cultures along the silk route, the Europeans could suppose that people fit into a limited range of behavior. The Bible, after all, spoke of city life even in the time of Adam and Eve, or at least the time of their son, Cain, who built a city (Gen. 4:17).

But suddenly from the East Indies, Africa, and especially the Americas it was clear that human beings were more various in thoughts and beliefs and morals and government and worship than had been dreamed of. Theories of the evolution of culture were attempts to make sense of all of this. John Locke was so struck by the hunting-gathering life of North American natives, that he proposed in his 1690 Two Treatises on Government that once upon a time the whole world had been like America. Jean Jacques Rousseau (1712-1778) had claimed that we humans developed from a state of savagery to one of civilization (though Rousseau had mixed emotions about how to evaluate this, whether as progress or as loss). The Scottish Enlightenment saw a number of interrelated theories by Hume, Adam Smith and others about stages of cultural evolution from savagery to their contemporary scientific times. They postulated a sequence from primitive hunting and gathering, to cities based on agriculture, to ancient commercial empires to the civilization of Europe. After two centuries of scientific developments, European intellectuals of the 18th century had reason to perceive progress in history; they considered themselves and their accomplishments to be the living proof of that.

It is not at all surprising that in the midst of all the 18th century evolutionary theories of the cosmos, the earth, and culture, there were also various theories of biological evolution. A hundred years before Darwin, a French mathematician and astronomer named Maupertuis (1698-1757) had speculated on whether the species on the earth now could have descended from earlier species, in fact through a process something like natural selection. In the end, though, he rejected the idea. It seemed too contrary to the Bible. In 1796, more than a dozen years before Darwin's birth, his grandfather, Erasmus Darwin, wrote a book entitled Zoonomia, in which he proposed there had been a progressive biological evolutionary process.

The most important evolutionist of the early nineteenth century was Lamarck (1744-1829). In a work entitled Philosophie Zoologique (1809), he argued that evolution took place through the acquiring of new characteristics through the life experiences of the organism, characteristics that were then passed on to the next generation. A giraffe who stretched his neck to reach leaves high on a tree would acquire a longer neck, and would pass on the slightly elongated neck to the next generation. If the new giraffe stretched just a bit further, it would hand on a yet longer neck. Unfortunately for Lamarck, there was a fair amount of evidence against this. After centuries of circumcision among Semitic peoples, newborn boys still had not acquired this characteristic. Yet for those persuaded that there had been an evolutionary process, it was necessary to find some theory or another to explain how it had happened. In the absence of a competing theory, Lamarck's was long supported by many.

Though many religious people rejected theories of geological evolution on the grounds that the bible told a different story, early geological theories were nonetheless not intrinsically unreligious. One 19th century idea, for example, was that the geological record was evidence of frequent divine interventions. It looked as though there had been mass extinctions of species every so often. At points in the geological strata, entire groups of fossils that had been abundant would suddenly disappear. A few layers higher would then show relatively fewer fossils of any kind. In still higher layers there would be a great increase in the diversity and number of fossils, many of them from new species. An opinion favored by many was that God, for God's own inscrutable purposes, had wiped out most life at various times, and then created new life forms.

This evidence of mass extinctions and then the appearance of multiple new species served as extra reason to see God intervening miraculously in nature to guide its progress. Louis Agassiz, for example, a famous 19th century anti-evolutionary naturalist, supported the earlier view of George Cuvier, a famous French paleontologist, that there were 60 to 100 various mass destructions of old life forms and the appearance of new ones, and that these were God's work: "Here again the intervention of the Creator is displayed in the most striking manner, in every stage of the history of the world," said Agassiz.

Belief that God had at least planned nature’s course was common. When Darwin was at school at Cambridge, learning to be a naturalist himself, he had read William Paley's, Natural Theology, that very thorough deistic argument for God's existence based on the order of nature.

Recall that one of the original purposes of deism was to overcome the divisiveness of religion. The many individual miraculously given revelations of the world, whether to Moses or Paul or Hindu Rishis or Mohammed helped to divide people. Deists looked for what could be common to all human beings everywhere, and knowable through human reason without need to rely on local revelations.

William Paley is one of the last great deists.  He elaborated the kind of argument that originated with the ancient Stoics, was used again by medieval thinks such as Aquinas, and was very popular among 17th and 18th century deists. But the early 19th century, however, an enormous amount more was known about the natural world.  So Paley could appeal to instance after instance of intricate and well-functioning design in nature.  This design could be evident to any person of any culture and any era, Paley thought.

Unfortunately, Paley tended to overlook an important aspect of early deism.  He showed, to his satisfaction at least, that the universe as a whole and each of it countless parts had to have been planned and put in its current order by some supreme Intelligence, such as people called God.  Paley did not, however, continue to emphasize that this God was always at every moment sustaining this universe in existence.  Belief in the ongoing sustaining activity of God had made God fully present to every event in the entire universe, as far as the early deists were concerned.  Without this emphasis on the sustaining presence of God in all things, it was easy for many people to begin to think of the God of deism as an absent God, one who had planned everything and set it in motion but then ignored it.  This is the kind of deism Nichols complains about.

Selection from:
WILLIAM PALEY (1743-1805), NATURAL THEOLOGY 1802

Statement of the Argument
In crossing a heath, suppose I pitched my foot against a stone, and were asked how the stone came to be there, I might possibly answer, that, for anything I knew to the contrary, it had lain there forever; nor would it, perhaps be very easy to show the absurdity of this answer. But suppose I found a watch upon the ground, and it should be inquired how the watch happened to be in that place, I should hardly think of the answer which I had before given--that, for anything I knew, the watch might have always been there. Yet why should not this answer serve for the watch as well as for the stone? Why is it not as admissible in the second case as in the first? For this reason, and for no other, viz., that , when we come to inspect the watch, we perceive (what we could not discover in the stone) that its several parts are framed and put together for a purpose, e.g. that they are so formed and adjusted as to produce motion, and that motion so regulated as to point out the hour of the day; that, if the different parts had been differently shaped from what they are, if a different size from what they are, or placed after any other manner, or in any other order than that in which they are placed, either no motion at all would have been carried on in the machine, or none which would have answered the use that is now served by it. To reckon up a few of the plainest of these parts, and of their offices, all tending to one result:--We see a cylindrical box containing a coiled elastic spring, which, by its endeavor to relax itself, turns round the box. We next observe a flexible chain (artificially wrought for the sake of flexure) communicating the action of the spring from the box to the fusee. We then find a series of wheels, the teeth of which catch in, and apply to, each other, conducting the motion from the fusee to the balance, and from the balance to the pointer, and at the same time, by the size and shape of those wheels, so regulating that motion as to terminate in causing an index, by an equable and measured progression, to pass over a given space in a given time. We take notice that the wheels are made of brass, in order to keep them from rust; the springs of steel, no other metal being so elastic; that over the face of the watch there is placed a glass, a material employed in no other part of the work, but in the room of which, of there had been any other than a transparent substance, the hour could not be seen without opening the case. This mechanism being observed (it requires indeed an examination of the instrument, and perhaps some previous knowledge of the subject, to perceive and understand it; but being once, as we have said, observed and understood), the inference, we think, is inevitable, that the watch must have had a maker; that there must have existed, at some time, and at some place or other, an artificer or artificers who formed it for the purpose which we find it actually to answer; who comprehended its construction, and designed its use.
I. Nor would it, I apprehend, weaken the conclusion, that we had never seen a watch made; that we had never known an artist capable of making one; that we were altogether incapable of executing such a piece of workmanship ourselves, or of understanding in what manner it was performed; all this being no more than what is true of some exquisite remains of ancient art, of some lost arts, and, to the generality of mankind, of the more curious productions of modern manufacture. Does one man in a million know how oval frames are turned? Ignorance of this kind exalts our opinion of the unseen and unknown artist's skill, if he be unseen and unknown, but raises no doubt in our minds of the existence and agency of such an artist, at some former time, and in some place or other. Nor can I perceive that it varies at all the inference, whether the question arise concerning a human agent, or concerning an agent of a different species, or an agent possessing, in some respect, a different nature.
II. Neither, secondly, would it invalidate our conclusion, that the watch sometimes went wrong, or that it seldom went exactly right. The purpose of the machinery, the design, and the designer, might be evident, and, in the case supposed, would be evident, in whatever way we accounted for the irregularity of the movement, or whether we could account for it or not. It is not necessary that a machine be perfect, in order to show with what design it was made; still less necessary, where the only question is, whether it were made with any design at all.
III. Nor, thirdly, would it bring any uncertainty into the argument, if there were a few parts of the watch, concerning which we could not discover, or had not yet discovered, in what manner they conduced to the general effect; or even some parts, concerning which we could not ascertain whether they conduced to that effect in any manner whatever. For, as to the first branch of the case, if by the loss, or disorder, or decay of the parts in question, the movement of the watch were found in fact to be stopped, or disturbed, or retarded, no doubt would remain in our minds as to the utility or intention of these parts, although we should be unable to investigate the manner according to which, or the connection by which, the ultimate effect depended upon their action or assistance; and the more complex is the machine, the more likely is this obscurity to arise. Then, as to the second thing supposed, namely, that there were parts which might be spared without prejudice to the movement of the watch, and that he had proved this by experiment, these superfluous parts, even if we were completely assured that they were such, would not vacate the reasoning which we had instituted concerning other parts. The indication of contrivance remained, with respect to them, nearly as it was before.
IV. Nor, fourthly, would any man in his senses think the existence of the watch, with its various machinery, accounted for, by being told that it was one out of possible combinations of material forms; that whatever he had found in the place where he found the watch, must have contained some internal configuration or other; and that this configuration might be the structure now exhibited, viz., of the works of a watch, as well as a different structure.
V. Nor, fifthly, would it yield his inquiry more satisfaction, to be answered, that there existed in things a principle of order, which had disposed the parts of the watch into their present form and situation. He never knew a watch made by the principle of order; nor can he even form to himself an idea of what is meant by a principle of order, distinct from the intelligence of the watchmaker.
VI. Sixthly, he would be surprised to hear that the mechanism of the watch was no proof of contrivance, only a motive to induce the mind to think so:
VII. And not less surprised to be informed, that the watch in his hand was nothing more than the result of the laws of metallic nature. It is a perversion of language to assign any law as the efficient, operative cause of anything. A law presupposes an agent; for it is only the mode according to which an agent proceeds; it implies a power; for it is the order according to which that power acts. Without this agent, without this power, which are both distinct from itself, the law does nothing, is nothing. The expression, "the law of metallic nature," may sound strange and harsh to a philosophic ear; but it seems quite as justifiable as some others which are more familiar to him such as "the law of vegetable nature," "the law of animal nature," or, indeed, as "the law of nature" in general, when assigned as the cause of phenomena in exclusion of agency and power, or when it is substituted for these.
VIII. Neither, lastly, would our observer be driven out of his conclusion, or from his confidence in its truth, by being told that he knew nothing at all about the matter. He knows enough for his argument: he knows the utility of the end: he knows the subserviency and adaptation of the means to the end. These points being known, his ignorance of other points, his doubts concerning other points, affect not the certainty of his reasoning. The consciousness of knowing little need not beget a distrust of that which he does know....
Application of the Argument Every indication of contrivance, every manifestation of design, which existed in the watch, exist in the works of nature; with the difference, on the side of nature, of being greater and more, and that in a degree which exceeds all computation. I mean that the contrivances of nature surpass the contrivances of art, in the complexity, subtlety, and curiosity of the mechanism; and still more, if possible, do they go beyond them in number and variety; yet in a multitude of cases, are not less evidently mechanical, not less evidently contrivances, not less evidently accommodated to their end, or suited to their office, than are the most perfect productions of human ingenuity. . .
[End of the selection from Paley]

Those who were religious in a less deistic way sometimes could accept the Romantic belief in a cosmic Force, in Nature as a divinity. Long before Paley, Spinoza (1632-1677) had proffered a pantheistic notion. He coined the expression Deus sive Natura, meaning(God/Nature), echoing Stoic thought of centuries earlier. Nature itself has an inner divine aspect guiding its processes.

As the reality of the evolution of the earth and perhaps of the universe sank in, some philosophers found other ways to picture a divine presence in it. Hegel (1770-1831) explained that the entire material universe was part of an evolving process in which the ultimate divine Geist or Spirit expressed itself and then returned to itself. (This was an echo of ancient Neoplatonism.) In 1844 Robert Chambers (1802-1871) published a work entitled Vestiges of the Natural History of Creation. He created a sweeping picture of cosmological, geological, biological, and human evolution, and spoke of the “transformation of species.” He argued that the whole process was divinely guided, but the book was nonetheless considered scandalously dangerous to religious faith. Chambers did not claim credit for the book, in fact. His authorship was not officially made public until 1884, 13 years after his death. Even those somewhat skeptical about religion had some belief in a patterned purposefulness to nature.

Thus in England Herbert Spencer's (1820-1903) popular evolutionism was quasi-religious. In a work published in 1851 he claimed that the whole universe was evolving, physically, biologically, and socially; and that this process of evolution was progressing towards higher moral sentiment. We human beings and our highest moral development are the goal of cosmic evolution, according to Spencer. He even argued that religious beliefs are products of "the religious sentiment," a feeling which arose as part of the process of evolution and should therefore be respected as part of evolution's purpose.

Herbert Spencer published his theory of social evolution 8 years before Darwin's Origin of Species appeared. He joyfully accepted Darwin's theory as a confirmation of his own claim that societies evolve from primitive to advanced, through competition among ideas and social forms, with the rule being: "survival of the fittest" (This was Spencer's phrase originally, not Darwin's, and was used by Darwin eventually in a later edition of The Origin of Species). Spencer's ideas were a reflection of 19th century capitalism. He believed that the pain and misery experienced by the poor, the abused laborers in the new factories, the backward cultures of the world, was part of a grand evolutionary scheme of nature that would automatically produce ever higher and better results. Totally free competition, however rough it might be in the short run, would create a wealthier healthier happier world eventually.

Spencer’s general theory came to be known as “social Darwinism.” This took a variety of forms. Sometimes it simply opposed public welfare. To help feed and clothe and house the poor, the social darwinists argued, merely helped the weak and incompetent to have more children and thereby spread inferior genes. At the extreme, social darwinism led to laws in support of what the English cousin of Darwin called “eugenics.” Positively, eugenics sought to encourage the smarter, stronger, braver, etc., to pass on their genes to subsequent generations. Negatively, it often led to laws permitting the forced sterilization of mentally retarded or chronically criminal. By the 1930s in the U.S., 37 out of the 48 states had some form of such laws on the books. (When Hitler came power in Germany, he cited the U.S. example in favor of his own version of eugenics.)

There were countless other responses to Darwin’s theory. A German biologist named Ernst Haeckel (1834-1919) illustrates a thoroughly materialistic way in which scientific perspectives of the 19th century often interpreted evolution, human life, and the nature and place of religion. He was a materialist in the sense that he disbelieved in any supernatural or spiritual substance. The stuff of the universe (what we today might call matter-energy) was all that Haeckel rejected all belief in the supernatural as superstitious, thought that the influence of religious leaders on government was quite harmful, and claimed that Christianity's traditional otherworldliness was bad.

Yet at the same time Haeckel was impressed with the power of thought. He concluded that mind, or power-to-sense-and-know, to give it a complex title, was an aspect of matter. We humans are entirely natural and material; and that includes our consciousness. "Consciousness, thought, and speculation . . . [are] functions of the ganglionic cells of the cortex of the brain." Ever since Platonist thought had been adopted by early Christians, the human soul had been understood to be a purely non-material reality, capable of existing even without a body. This division of the human self into material body and spiritual (non-material) soul is called dualism (There are numerous kinds of dualism, so this is a word to be reinterpreted in each context it is found.) According to Haeckel, however, what we call soul is a natural and material phenomenon, not a supernatural one or "spiritual" one. Because Haeckel believed in only one type of reality — material reality — he is sometimes called a “monist.”

Haeckel went beyond offering these ideas as science. He proposed that they be part of a natural religion, a kind of evolutionary-progressive religiousness in which the name God stood not for any supernatural reality, but only for the basic substance of the universe, accorded almost divine respect for its power to give rise to evolution and to thought. It was a monistic religion--i.e., one without the dualism of matter and spirit or nature and supernature. It was a kind of pantheism, which treats nature itself as divine, as Spinoza had.

At the same time he believed that the ethical teachings of the Christian and other traditions had much in it that was valuable. Human beings should live by an ethic of love of neighbor and also love of self. People should learn to be sympathetic to one another and even to animals. The family is important and must be supported, though the old idea that women are subordinate or inferior to men is harmful and must be eliminated. According to Haeckel, all of this can be learned from the evolution of the natural world. The process is a meaningful one, directed towards higher values. Knowledge and acceptance of this natural order is true religion. Here is almost a deist's attitude again, only now shifted from a static universe to an evolving universe and, more importantly, become pantheistic, no longer distinguishing God from the cosmos. Thus in Darwin's day there were various models of cosmic and life evolution in competition.

THE DARWINIAN REVOLUTION.

In 1859 Darwin published The Origin of Species, defending a theory of how biological evolution had taken place, one that he had arrived at almost twenty years earlier on the basis of a dozen prior years of studying natural history, including his five years aboard the Beagle in its wide-ranging sailings beginning in 1832. What Darwin provided was a thorough review of the relevant evidence for his theory, considering all the pros and cons. As is often the case, it was not the ingenuity of the theory that counted; others had similar theories before him. His general theory was already in the air in the writings of Adam Smith and Thomas Malthus, from whom Alfred Russell Wallace also picked it up later than Darwin. What was needed was the painstaking work of assembling all the relevant evidence and showing how it all fit together.

To say it another way, Darwin had to learn countless pieces of information about the characteristics and distribution of various life forms.  He then had to try to identify any patterns, in the sequence of fossils, in the geographical distribution of various types of birds, animals, insects, and plant, in the comparative anatomy of organisms.  Then he had to come up with a theory to account for all these patterns.  Then he had to test that theory against a wide range of further information for over twenty years, publishing brief samples of his ideas to get some feedback.  Finally, when it looked to him as though the evidence strongly supported the pattern and the theory he published his theory and the evidence in a book, part of whose title was The Origin of Species, so that others could critically evaluate and test his ideas.  That evaluation and testing has been going on now for over 145 years.  (It is not a coincidence that this paragraph describes Darwin's work by using the format of "the method of science" described in ch. 1 here.)

Darwin's The Origin of Species is a compendium of natural history, covering a wide spectrum of information, some gathered by him in the field and some from a vast array of reports by others. He was compelled to publish his theory in 1859 (he had already circulated a brief version of his theory for others to read in 1844) because Wallace was about to publish his own version. Feeling rushed, Darwin took pains to indicate that the single volume of 1859 was only an abstract of the information he had. He would have liked to produce the sort of many-volumed work that other Victorians took pride in offering, in order to provide a full description and analysis of the evidence.

Darwin's theory has three major aspects. The first is the reaffirmation of the general belief that evolution occurred: "descent with modification." This line summarizes the conclusion that present day species are modified descendants of earlier organisms. The next two aspects of Darwin's theory constitute his explanation of how evolution occurred. The first of these is that there is natural and partly random variation among offspring in a species, especially through sexual reproduction. The second is that there is a seemingly unplanned process of selection. It occurs most frequently through the struggle for survival. Most offspring die before they can reproduce. Their variant characteristics will not be passed on by them. The selection process includes sexual selection, wherein some males fail to mate, because they were rejected by a female or outcompeted by another male. Or the selection process might be driven by changes in climate or geographical isolation or by competition from a new intruder species. In any case this is a "natural selection" that determined what the next generation would be like.

Variation and selection constitute a "mechanism" of evolution in the sense that they require no vital force or spirits, no guiding hand of God, no Neoplatonist soul-power, to make evolution happen. Life forms are the products of an apparently unplanned and undirected process. The process is "lawful" in the sense that the variations in the offspring were at each stage just variations on a current species, not a wildly creative process producing utterly new forms of life in a single step. The process is also "lawful" in that there is a severe weeding out of possible life-forms by the environment and the competition for survival and reproduction. Environmental factors place clear limits on what life-forms can survive well and reproduce. Whatever the random variations that happen to occur in any species, in the long run the environmental conditions will support some and kill off others. The result is that surviving species are well adapted to the environment, adapted in thousands, even millions, of very specific ways through a process of what seemed to Darwin to have to have been a process of well over half a billion years. (We now say over three and a half billion.)

THE CHICKEN OR THE EGG?
The famous question of which came first, the chicken or the egg,
is answered by Darwin's theory of evolution in favor of the egg.

LAMARCK'S THEORY:
The chicken adapts to its environment. If its food is on rocky ground, for example, a constant pecking at this hard ground will produce a tougher beak. This change in the chicken will then be passed on to its offspring. So the change in the chicken leads to a new kind of chick, one with a harder beak, that develops in the egg.

DARWIN'S THEORY:
No matter how tough a chicken's beak gets that will not produce chicks with harder beaks. (Just as no matter how often the tails are lopped off a certain species of dog, the pups are nonetheless born with full-length tails.) But no offspring is identical to its parents. There is natural variation among offspring (even in non-sexual reproduction some variations appear occasionally). So the egg comes first: a variation in a species appears in the offspring.

CONFUSION OF LANGUAGE:
Evolutionists unfortunately sometimes speak of "adaptation" as the mechanism of evolution. By this they mean only that those variants that happen to be better adapted to the environment in which they live will have a better chance at surviving to reproduce and pass on their particular genetic pattern: "reproductive success." But evolutionists do not mean that the individual living organisms adapt to their environment, like the individual chicken might adapt to hard ground by developing a hard beak.

CONFUSION OF IDEAS:
A major misunderstanding about the evolutionary process is the idea that one species gradually changes until it turns into another species. This sort of thing might occasionally happen; it is hard to say for sure. But the evidence indicates that when a new species appears it may usually do so while the old species continues. A new species is an off-shoot from the old species, not a transformation of the entire old species. A species may in fact co-exist with several of its own off-shoots, though perhaps not in the same territory where they could be in direct competition with each other.

Darwin's theory supported what many then still called a "mechanistic" or “materialist” model of reality. It did this partly just by sustaining the scientist's faith in naturalistic explanations of things rather than supernaturalist ones. It added to the impression that the physical forces at work in the universe could account not just for cosmic and geological processes but also for the development of life forms and even human beings. The inner workings of living things and how they manage to transmit their basic nature to their offspring was still unknown. But if the evolution of life in the broad sense could be explained as the workings of natural patterns, just as the formation of geological strata and the orbits of the planets could be, then it would seem that everything, life included, could be reduced to mechanical or materialist explanations. It is easier now and more accurate to call this a naturalistic account.

A UNIVERSE IN FLUX
An important and disturbing implication of Darwin's theory was that it agreed with the proposal put forth by Robert Chambers in his originally anonymous work, Vestiges of the Natural History of Creation, 1844. This was the proposal that species were not “fixed,” i.e., permanent or changeless. From before the time of Aristotle, in Greek philosophy, as well in Hebrew (and later Christian) religious thought, it had been assumed that there were basic essences or natures that accounted for why there were dogs and tomatoes and spiders and people. Jews and Christians read the Bible which said that the species were created by God in the beginning. Plato and Aristotle believed that a dog was a dog because a dog had a dog's nature. But Chambers and Darwin denied that dogginess necessarily remain the same down through the millennia, regardless of historical change.

Our contemporary viewpoint, derived partly from Darwin's theory, is that the name we give a species in the long run is just a convenience. "Dog" is not a permanent thing. The human mind can learn to think of dogginess in a certain way that can be preserved in books and films for centuries or more, giving an kind of artificial permanence to dogginess. But there is no pure essence of dogginess established at creation that a set of animals will continue to reflect. The current descendants of wolves might all go extinct, but first give rise to a different kind of canine that will go by the name of dog, though we would not be tempted to call it that if we saw it today.

If the human person is also a product of the evolution of the cosmos, then perhaps the same is true of human beings as of dogs. Homo habilis (tool-using human) existed two million years ago, in form as much like an ape as like homo sapiens, yet human enough to make tools. Homo erectus was surveying the territory about one million years ago, with a larger brain than homo habilis. Slope-browed Neanderthals roamed and hunted more than one hundred thousand years ago, only to be replaced (outbred? outhunted? interbred with competitors?) by Cro-Magnon humans by around forty thousand years ago. We are descendants of these flat-foreheaded, large-brained hominids, the sole surviving hominid of many that once existed. Our descendants in a half million more years may be quite unlike us.

What, then, is the essence of humanness? When we fix the edges of what we will call "human" by defining the human as the rational animal or the tool-using hominid or any other definition, there can be some uncertainty on where we place those edges. It could be like deciding when a hill is high enough to be a mountain, or when an island is big enough to be a continent.
Evolution does not mean that everything is constantly changing or changing at the same rate. Many species do survive for very long times unchanged. Some of the prokaryotes (tiny cells without nuclei) may have existed for a few billion years more or less unchanged.

Two paleontologists, Stephen J. Gould and Niles Eldridge, stirred things up by claiming that the process of “descent with modification” was rather irregular, with jerks and jumps here and there in the line of modifications. They call their theory “punctuated equilibrium.” Most species seems to survive unchanged for even millions of years (the equilibrium). But most species also have suddenly disappeared, sometimes as part of enormous “wipeouts” of species, to be replaced before long by many new species (the punctuation). Arguments about punctuated equilibrium are part of an intramural battle, however, among people who all agree that each species is a variation on former species and that all together are variants on a basic DNA code active within the nucleus of each cell of every living being, as a result of a 3.5 or more billion year natural process of descent with modification..

The various life-forms, therefore, are not each autonomous in identity, a direct reflection of some specific archetype (like Plato’s heavenly forms, or like ideas in the mind of God). Rather each life-form is a transitory moment, a temporary expression of an ongoing process of change, with each moment blending into the next. The process is very slow. Our ancestors can be forgiven for failing to notice it and thinking instead that the basic life-forms are somehow fixed and immutable and forever distinct from one another.

As we have seen earlier, in the 14th century the nominalists had asserted that there were no true "necessities" in nature because God could have made an infinite number of universes, each with endless degrees of variation on the other. These nominalist argued against the Aristotelian scholastics who thought that there were certain necessary and fixed logical categories of things that God would naturally follow in creating a universe. Some even argued that God would have to make the single universe that was the best of all possible worlds, probably following the Great Chain of Being format with each niche in the cosmos filled up with its proper type of thing or animal or person or spirit-being from the very beginning.

In Darwin's theory the nominalists won, but in a way they would not have celebrated. Darwin's theory eliminates the Aristotelian idea of fixed logical categories. The cosmos is instead just a process, with an infinite number of universes that might possibly have developed. But the nominalists attacked belief in fixed categories in order to make room for God to do as God pleased. Darwin eliminated fixed categories by creating a model of a universe in which there is no clear sign of a higher Power at work. God could be working, of course, without leaving signs. But after Darwin it has no longer been easy to prove God’s existence as Paley did through the order of nature.

Darwin’s theory thereby gave a little extra ammunition to naturalism. As a scientific theory, of course, it had to follow a methodological naturalism, looking for natural cause to explain things. But Darwin’s theory also strengthened the position of those who were cosmological naturalists, because Darwin’s theory did not require any divine interventions to explain the sequence of the development of life forms.. Every life-form, just like every temporary feature on the planet and every temporary form of the solar system and galaxy and universe, is one more passing way in which the basic stuff of the universe can exist. All things that are around us now, and ourselves as well, are variant ways that matter-energy/space-time, as we now think of it, can take shape before moving into new shapes. And if everything is a temporary shape taken by matter-energy, then in a sense everything is just one thing: matter-energy, operating according to the basic physical natural laws of the universe. In the 20th century the astronomer Carl Sagan could say "The cosmos is all that is or ever was or ever will be;" and that we are "the remote descendants of the Big Bang." From the beginning to now there is only the stuff of stars of which all things are made, all acting in accordance with the regularities of nature. Belief in a God who created all this is still possible, of course. But the evidence seems to obscure any divine presence.

DISAGREEMENTS WITH DARWINISM

There were two closely related kinds of major disagreements with Darwin's theory of just how evolution took place. One was the belief that there was an inner purposefulness to evolution; the other that each life process had to have some inner vital spirit, like a soul, guiding its individual development and growth.

Herbert Spencer's ideas represent the first form of disagreement. He claimed there was a special direction to evolution, a kind of invisible hand at work (You may recognize this ideas as a variation on Adam Smith’s economic thesis that a free market economy would promote efficient and productive trade as though it were directed by an invisible hand.). Henri Bergson later promoted a vaguely similar set of ideas in France, claiming that nature has an elan vital, a kind of purpose-directed inner urge.. Hegelian and other Romantic or vitalist ideas did not disappear from Germany. This meant that there was ongoing support for models of the evolving universe in which there was a purposeful order, perhaps even one planned by a Creator.

The other major disagreement with Darwin's theory was the conviction that there were too many aspects of life processes that Darwin's mechanistic theory could not explain. It was one thing to accept that an already existing animal could give birth to a near copy of itself, as in Darwin's theory. It was something else to show how this little copy had within it the power to guide wounded tissue to heal itself or, in the case of the salamander, to produce an entire new tail.

The German vitalist Hans Driesch could still argue in 1914 that "The regeneration of the salamander confutes, as is well known, the orthodox Darwinism of Darwin's followers . . . ." Driesch concluded that "The whole life-process is in no way the result of physico-chemical events, but rather controls them." Not just "descent" but an additional guiding force was needed to explain the whole range of life activities, Driesch claimed; so Darwin's model of a purposeless mechanical universe was not adequate.

SOCIAL CONSTRUCTION OF REALITY?

Those who still object to Darwinian theory have sometimes taken refuge in the position of those described in the first chapter, on the scientific method, as social constructivists. They argue that all scientific theories are products of certain social conditions. Some of them think it evident that Darwinism is a product of 19th century capitalist theory, that Darwin’s theory succeeded not because it is supported by adequate evidence but because the theory supports what a capitalist society wanted and wants to believe. Survival of the fittest; free competition to weed out the weak or inferior — these social darwinist ideas fit with the rugged capitalist individualism that many in the culture promoted and still promote.

But the objections to Darwinism just cited make it clear that among 19th scientists there were still various competing models of reality. There were lingering echoes of a Neoplatonist or Aristotelian model and method. In Germany, for example, "idealistic morphology" was popular in the early 20th century. According to this theory, each species represents a morphological type. These types were similar to the natures or essences of Platonic or Aristotelian thought, and the fundamental way of grasping these natures was through insight or intuition, rather than through a slow empirical accumulation of descriptions of their characteristics and behavior. Insight provided knowledge of the inner essence. The position was a kind of vitalism in the minds of its adherents, who sought to grasp the basic types of life in order to know and influence the basic life-forces that dwelt in living beings and gave them their type-form of life.

Spiritualism was also popular among some 19th century scientists. This was belief that the spirits of the dead could be induced to communicate with the living with the help of a “medium.” Alfred Wallace, whose own theory of evolution forced Darwin to publish, ended up attending seances and was convinced by them of the validity of spiritualism. He was joined in this by other scientists, such as Francis Galton. Wallace used the seances as empirical evidence of the reality of the spirit domain. The Society for Psychical Research was founded in 1882, by a group of people that included bishops, astronomers, and chemists. Their intent was to demonstrate empirically the reality of spirits. Reliable evidence has continued to elude them, however, as well as those still searching for such evidence today, by the admission of the Society itself.

There were many hypotheses in the 19th century that sound quite strange to us today. Some were materialist. For a time physiognomy--a theory that faces reveal character and abilities--was popular, followed by phrenology (which absorbed physiognomy). The materialist assumption here was that the shape of the physical brain was a clear indication of the mind, implying that mind might be nothing more than brain. But no amount of materialism was enough to provide the evidence to support either theory. In the end evidence counts more than assumptions. Both spiritualism and materialism may begin as prejudices or assumptions, but to survive as part of science either of them would require adequate evidence.

Moreover, both capitalism and socialism, and various forms of each, were available to inspire evolutionists in the 19th century. Thomas Huxley, one of Darwin’s strongest supporters, nonetheless argued against apply the model of biological evolution, “nature red in tooth and claw” in Tennyson’s words, to social order. Precisely because nature was cruel it was all the more important for civil society to support the weak and poor and help them improve. In Huxley’s case, and those who agreed with him, the apparent fit between darwinism and capitalism was not at all the motive that made them support Darwin’s theory.

EVOLUTION AND THE PROBLEM OF EVIL IN THE WORLD

Ever since monotheism arose there has been what theologians in the West have come to call “the problem of evil.” There seems to be real evil in the world. The word “evil” here does not apply only to human acts or intentions; it applies to any human suffering no matter how it is caused. Thus there are moral evils, caused by human beings; there are also “natural” evils, caused by disease, drought, eathquakes, floods, death, and any other natural events that causes pain or deep loss. The problem is this: if the universe is under the guidance or control of an omnipotent, omniscient, and all good God, why does this God allow such evils?

Even before the idea of the evolution of life was well accepted David Hume had found in the order of the universe only ambiguous support for belief in the traditional God who omnipotently and omnisciently and all-benevolently planned and created the universe. There was too much evil, too many flaws in things; and in any case it was difficult to move from our imperfect knowledge to the ultimate cause of everything. In the next century John Stuart Mill, a contemporary of Darwin's, had similar reservations, especially about the limited competence of any creator of this messy world. Mill's judgment is hardly surprising in the light of his view of nature. Mill describes it as often the enemy of human needs:

In sober truth, nearly all the things which men are hanged or imprisoned for doing to one another, are nature's every day performances. Killing, the most criminal act recognized by human laws, Nature does once to every being that lives; and in a large proportion of cases, after protracted tortures such as only the greatest monsters whom we read of ever purposely inflicted on their living fellow-creatures.

Mill goes on listing the many evils that nature does "with the most supercilious disregard both of mercy and of justice . . . ."

Stephen J. Gould, one of the most popular science writers of the 20th century in the U.S. pulled from Darwin’s own writings the example wasps who plant their eggs in living caterpillars. When the eggs hatch the new larva eat the living caterpillar, but carefully leave to the end the parts of the caterpillar that will keep it alive until the last possible moment. Both Mill and Gould see such aspects of nature as lacking in benevolence.

The upshot is that Darwin's theory made a number of religious beliefs appear to be unnecessary or improbable hypotheses. The theory of evolution has provided reason to suppose that we humans might be entirely products of natural processes. There is no clear evidence to support belief in a special interventions by God in the course ofnature. Neither does Darwin's theory provide support for belief in a divine Providence which guides the processes of the universe nor a divine Plan which established an order to those processes. The amount of randomness, of what seems like "waste," and even of what would be cruelty, perhaps, in the process of evolution seems even contrary to belief in a divine Plan or Providence. Darwinian theories have had this negative effect on religious beliefs not by direct attack, but by making plausible an alternative naturalistic model of the story of life, a model that requires no Plan or Planner to explain it. (The ideas of Cornelius Hunter near the end of this chapter will illustrate this further.)

CREATIONISM

Directly opposed to Darwinism is the position of "young earth" creationism. "Creationism" is a general name that could stand for any belief that God created the world, even a belief that God created it so it would evolve on its own but in the direction of intelligent life like us. That would mean that the Anthropic Principle is a kind of creationist position. But in fact the name is not used that way. Today it stands for those who are opposed to the theory of evolution in the name of the Bible and religious morality. Creationism comes in two forms. Old-fashioned creationism, so to speak, is young earth creationism. (We can pass over in silence those who are still flat-earthers.) There is also a “new creationism” focused around the movement known as “Intelligent Design,” described later here.

Young-earth creationists (hereafter just “creationists) assert that God made the world in six days, resting on the seventh (Gen. l:1-2:4a; also Gen. 2:4b-3:25). During this period God made all the basic "kinds" (as the King James version expresses it) of vegetation and water inhabitants and birds and land animals, and finally the man and the woman who are the ancestors of all the human race. Furthermore God destroyed all animal life on the planet during the great flood of Noah's time except for the animals which Noah and his family took aboard the ark with them (Gen.6:5-9:17), so that all animals alive today are descendants of these sea-faring ones.

Of special importance is the fact that we humans are descended from the original parents who were made directly by God at the beginning of the world, and not descended from some other animal stock. We are of a fixed nature, as God intended us. Whatever is naturally human is therefore morally required, assuming that it is possible to know just what God intended human nature to be like. Creationists link belief in evolution with secular humanism, moral decay, and atheism, all part of one great apostasy from God. By calling us all animals, say the creationists, evolutionists exempt us from any moral law.

20th century creationists came to claim that their analysis is a rational and scientific one, though some acknowledge that this is just to help unbelievers see the truth, not to rely on their human reason instead of on God's revelation. The goal behind calling creationism scientific is to try to get it into science classes in the schools as an alternative theory to Darwinism.
Whatever the motive or justification, they offer three kinds of arguments: 1) that evolutionary theory leaves unexplained or deals badly with a number of facts, 2) that evolutionary theory turns out to be more of a faith than science, and 3) that creationists have a better alternative interpretation of the evidence.

There are many facts, the creationists first of all claim, that the theory of evolution does not account for well at all. A living cell is so incredibly complex a form of life process and pieces that it is clearly impossible for a cell to evolve by chance. The odds are so against the possibility that it is not merely a matter of billions to one but of astronomically higher odds. So it is reasonable and even necessary to suppose that only God's intervention could produce life.

Other fallacies abound, say the creationists: paleontologists measure the age of fossils by determining what geological strata the fossils come from and the geologists determine the age of the strata by the fossils. This is circular. Radioactive dating procedures are unreliable. The geological strata are not neatly laid out to read time's record from them; instead they are broken and sometimes upside down from neighboring strata. Individual aspects of various species could not have evolved: the bombardier beetle which sprays its enemies with acid could not have evolved acid-production before having a good means to get rid of the acid or it would have dissolved its innards in acid. Whales could not have evolved from land-dwelling mammals, as evolutionists think, because if the nose passages had to move from the front as they are on a cow to the top of the whale as they now are, then the poor intermediate form of the animal as it evolved from cow to whale would have drowned from rain dropping in its nose on land or from inhaling sea-water in the ocean.

The scientific fact of entropy--that all isolated systems tend to less and less order--goes contrary to the idea that this world could have had a more and more ordered progression of life-forms during the past three billion years. It would take something like a life-forming power to pull matter into complex order contrary to its natural tendency to become more disordered.

Most important of all, say the creationists, there are serious gaps in the fossil record, with no direct evidence of a transition from one species to another, and there are no instances of anyone seeing the evolution of one species from another taking place. The "missing link" problem is not just about transitions from apes to humans, it is a problem for evolution in general.

In addition to all these problems with facts, creationists have a problem with the very nature of evolutionary theory as scientific. Science works by experimentation and observation of events, creationists claim. Evolutionists cannot experiment on the events of the past centuries, nor can they observe those events. Evolution is therefore just a theory, not science. It is in fact a kind of faith, an unproven and unprovable vision of how things might be which denies that God or any other supernatural agent might be responsible for events and claims instead that only natural causes are real. It is a materialist and naturalist faith, in that it supposes rather than proves that all physical events have natural material causes.

Finally, the creationists offer an alternative explanation for the evidence that evolutionists point to, the evidence of fossils and geological layers and similarities among animal species. In the beginning, say the creationists citing scripture, God made all the basic kinds of animals, making them apparently according to an economical pattern with a few basic elements God chose to use over and over again, such as giving all mammals four appendages (showing up as flippers, say in some sea mammals).

The creationist say the theory that all animals have descended from these distinct kinds fits best with the evidence, inasmuch as there is a lack of evidence of any "transitional species" that are halfway in the evolutionary process from one general kind of species to another, such as from fish to amphibian or amphibian to lizard. The fact that a single God made all the basic kinds also explains adequately why many animals seem to have a family resemblance among themselves.

There may well have been a partial evolution of many species from a single "kind" of animal aboard Noah's ark, giving some such as the horse, zebra and jackass great similarity. But this is microevolution, variations arising from a single `kind' created by God. It is not the macroevolution of one entire kind out of another kind, as Darwinians claim.

The many layers of fossils and geological strata can be explained by the flood which Noah survived, a flood sent by divine intervention. A flood which drowned the world would leave many fossils. Rock and dirt and clay would settle at different rates, leaving different kinds of layers, each with it own typical fossils, because the rate of death and of settling would also vary for different animals with different swimming abilities and with different specific gravities. In the extreme a few still propose the answer suggested by Edmund Gosse in his book Omphalos, that God made the universe as we now see it to look as though it had evolved over many billions of years when in fact God made it only about 6,000 years ago. Gosse argues that God would have made Adam and Eve each with a belly-button (omphalos in Greek), even though they never had an umbilical cord; and would likewise have made all the trees with rings, as though they had been growing for hundreds of years. So the fact that the geological strata gave the appearance of having been formed over millions of years was not evidence that such a long time had actually occurred.

The creationist literature repeats these same challenges over and over again, though recently the strongest attacks against evolutionary thought have focused on the supposed lack of transitional forms from one type of species (from one genus or family or class, etc.) to another. A person exposed only to such creationist literature can be excused for having serious doubts about evolution. But in spite of the vigor of creationist attacks, these criticisms of evolutionary thought are only superficially competent. The creationist literature ignores, whether intentionally or through ignorance, a vast amount of relevant information. Even an introductory college textbook in biology or geology provides sufficient information to shatter the creationist analyses. [We will review some of this evidence in class.]

In general, the creationists' claims are not arguable hypotheses with perhaps some evidence for them. These claims are scientifically incompetent, made by people who are ignorant of the evolutionary science, or who are carelessly indifferent to truth and unwilling to correct themselves when confronted with a thorough scientific analysis. Most creationists are sincere religious people. A few even have Ph.Ds in some scientific area (biochemistry seems to attract some of them.) They are poorly served by a few creationist leaders who crank out materials with little care to do the necessary extensive survey of evidence and careful evaluation of it. The general mind set seems to be to first presume that the Bible must be literally true in a historical sense. This seems to carry with it a conviction that the theory of evolution simply cannot be correct. So no matter how poor the creationist science, if it attacks the theory of evolution it is legitimate.

In recent years as creationists have gone public, arguing that creationism should be taught in biology classes in schools, scientists have made the effort to address each one of the claims about facts, about the nature of science and about creationism as an alternative hypothesis to evolutionary theory. Creationism should by now be completely discredited. But it can sound plausible to anyone not very familiar with the history of geology and the long-term story of coming to terms with the great variety of geologic strata and the sequences of fossils in those layers.

THE NEW CREATIONISM: INTELLIGENT DESIGN

The current proponents of Intelligent Design, a phrase to be explained in a moment, should probably not be called creationists strictly speaking. The name was given to them by Robert Pennock in his book Tower of Babel criticizing them. Their basic position is that the life forms we see around us could not have come from an unplanned and undirected evolutionary process. They put forward various arguments to show first of all that some forms of complexity in life cry out that they had to have been designed because they could not have happened by any combination of natural laws and accident.

From this, however, they do not arrive at a deistic position. Rather they add that the Planner or Designer must also have intervened, at least to produce the first life on the planet, and probably to produce every new family or genus in the history of life on the planet. So this movement might better be called the new interventionism rather than the new creationism.

The ID proponents do share some ideas with the young earth creationists. Many of them attack naturalism in all its forms. They argue that the appearance of at least the first life on this planet is so incredibly improbable it could not possibly have happened without both intelligent planning and intervention of some sort. They argue that there is inadequate evidence for evolution, especially because of a lack of intermediate forms. Most ID proponents differ from the young earth creationists, however, in that they accept the great age of the cosmos and the earth, they accept the geological evidence that there has been a long sequence of life forms that have appeared and gone to extinction over many millions of years.

One of the major forces in the ID movement is Phillip E. Johnson, an expert on criminal law procedures. He published Darwin on Trial in 1991 to attack evolution in particular, and Reason in the Balance in 1995 to attack naturalism in all its forms. But the person who has done the most to make the new interventionism respectable is William Dembski, who applies his two Ph.Ds, in mathematics and in philosophy, to the task. To some extent he only shares the arguments of earlier anti-evolutionists, reformulating the various reasons given by young earth creationists to the effect that the theory of evolution lacks adequate evidence. He also, however, uses his knowledge of mathematics to calculate the odds against something as complex as a single living cell coming into existence by a series of chance arrangements among various amino acids. The young earth creationists had done this also, but they never engaged in Dembski’s elaborate analysis of the odds.

Dembski defines certain states of affairs as “complexly specified information” (CSI). By this he means not merely complex realities. The weather is complex. CSI is better represented by something like the DNA molecule, which is structured in accordance with very specific information. The DNA molecule is not merely highly complex; it is also complex in the way coded instructions in a computer are complex, or the way an encyclopedia description of how to build a Boeing 747 are complex. We immediately recognize that the informed complexity of a 747 or an encyclopedia has to be the result of intelligence. The DNA molecule has enough well-ordered information in it to instruct a single fertilized cell how to start and carry through the extraordinarily complex process of producing an entire organism. Therefore it must have been designed also.

There are only three ways events can occur, says Dembski. One of them is by “necessity.” Here Dembski is borrowing the ancient Epicurean word for the laws of nature. The second is by chance, or accident. The third is by design. Dembski offers a “design filter.” When you see some CSI ask if natural laws alone could have produced it. The basic law of nature is entropy — things fall apart. Some complexity can be created by the intersection of natural laws and chance such as the weather. But the weather does not get increasingly complex in the specified, information-guided way a single living cell does. When neither necessity nor chance nor a combination of those two can produce the CSI in question, that leaves only design to account for it. The existence of even a single living cell makes it highly probable that a designer has been at work.

Those who criticize ID argue that it consistently overlooks the core of the theory of evolution, which is natural selection. This is a fourth source of complexity, in addition to chance, necessity and design. Natural selection is constantly at work on any given results to date of the interaction of nature’s laws and chance. It sorts out the results: those that are better suited to survive, more often do survive. Those that are better adapted to take advantage of features of the environment, are better suited to survive. Even a complex amino acid chain, many of which appear spontaneously in nature, may survive longer than other chains. If a single chain, out of multiple billions produced by chance and necessity over millions of years on this planet, should have the ability to self-replicate, that is sufficient to set in motion all subsequent forms of natural selection on the replications of that chain. Eventually one descendant of that original chain may be so complex as to be called living. We have no way of knowing whether this is certainly the way life began. We have no way of knowing whether something like this may have happened once or a million times. But the theory of natural selection shows at least how it is possible that life could originate without a designer. Darwin’s theory is powerful.

In addition to Dembski’s theoretical arguments about the odds of CSI happening without a designer, the biochemist Michael Behe, in his book Darwin’s Black Box (1996 and 2003), claims that he has identified some concrete instance of kinds of complexity that fulfill the requirements to be CSI. He calls them “irreducibly complex” processes or structures.

A mousetrap, his major example, illustrates what he means by this. A mousetrap is an arrangement of parts all designed to work together to achieve a certain goal. A mousetrap has a base, to which is attached a framework with a spring, a bait-holder, a release trigger, and a metal bar which, when released, snaps across the mouse to kill or imprison it. Remove any single one of those parts, and there is no longer a functioning mousetrap. It is irreducibly complex. It could not have evolved piece by piece, starting with a base, then adding a spring. Such a contraption would not function. Even if a bait-holder were added, it still would not function. Even adding the release trigger would not be enough. All the parts must be assembled at once; they cannot slowly evolve by natural selection. The mousetrap clearly had to have been designed.

Behe has identified four or five different biochemical structures or processes that he says show exactly this kind of irreducible complexity. Behe does a good job of making complex biochemistry rather clear in his book, describing the cascade of events that go into blood clotting or the very complex mechanism of the flagellum of certain paramecia. He claims that these are irreducibly complex, by describing how all the parts of these mechanisms must all work together, and also by claiming that there is no literature in the biochemistry journals that shows how such complexity could have come about by a step-by-step process of natural selection.
Behe has many critics, however -- other biochemists who provide information showing how it is at least possible for these supposedly irreducible structures to have evolved step-by-step. The major element in their analysis is the long-standing set of observations that in the evolutionary process old parts of an organism can be adapted to new uses. The newly adapted part can take over for an older part that does not quite work as well, and which eventually disappears. At that point the new part has become essential, part of an irreducible complexity. But once upon a time it was not essential; it evolved into that function.

The sharpest critique of Behe’s arguments comes from those who point to very specific information in the biochemistry journals that does in fact show how some irreducible complexities like the flagellum structure could have come about step-by-step. There are flagella now functioning that do so with fewer parts or different parts than the ones Behe says are essential for any functioning flagellum. It is not hard to see how a new part could be added to improve the function a bit, and old parts drop away.

Kenneth Miller is one of Behe’s major critics. Miller is also a biochemist (and like Behe is also a Catholic). In addition to citing articles in the biochemical journals on how Behe’s irreducibly complex structures could have come about through step-by-step evolution, Miller also attacks Behe’s illustration of the mousetrap. Miller ingeniously shows how you can remove this part or that from a mousetrap and still have a functioning though poorer mousetrap. He also shows how a mousetrap could “evolve” from a tie-clip (a spring clip) to a better tie-clip to a poor mousetrap to a better one.

Behe could note that illustrations cannot always be perfect. But on the other hand Behe thought the mousetrap was irreducibly complex because he did not have the imagination to see how it could evolve step-by-step. It is always possible that he is missing possibilities for the evolution of the other examples he sees of irreducible complexity. Miller thinks he has the evidence in the journals that this is so. Without realizing it, Behe was using an “argument from ignorance.” It is an essential part of any claim that nature alone could not have made a certain thing happen so there must have been a supernatural intervention. On the surface it is an argument that says that a certain even could not have been caused by natural causes. But in reality it is an argument that says I do not see any way this could have been caused by natural causes. What a scientist tends to do in such a case is to take this as a challenge to see how it could have a natural cause, something that science can study and learn from.

The ID proponents make their own job harder than it need be. They are not just arguing that the universe shows clear signs of design. If that were all that they sought to show, they might be happy to join with Miller in supporting the anthropic principle, as he does. But they want also to show that God intervened.

Sometimes they seek only to show that God intervened at a few crucial places. One ID proponent lists just four occasions that he thinks may qualify. The first three are topics science can study: the creation of the universe, the origin of the first life, and the origin of the first humans. (The fourth is the redemption by Jesus, which is not a scientific topic.) But most ID proponents still argue against the reality of macroevolution — that the offspring of a species, in a process of descent with modification, can gradually produce entirely new and different species or genera or families or organisms. If macroevolution does not happen, then every single genus, or at least every single family of life forms on the planet was a product of a special creation or at least a special intervention by an intelligent designer. Because there have been millions of families of organisms, God must have been extremely active.

This makes the ID case perhaps more religiously implausible. As an ID proponent named Cornelius G. Hunter has delineated the issue, If there is a God who is willing to intervene often to control the whole exceedingly long life process on this planet, this God would seem to have acted rather strangely. Hunter does not mean to show that it is improbable for God to have worked the way evolution seems to. He means only to argue that evolutionists use theological language at times, arguing about what God would or would not do. But theology has no place in science, says Hunter. If evolution is based on theology then it should be kept out of science classes in high school. But to show that evolutionists sometimes talk like theologians, Hunter lines up some of the facts of the history of life on the planet, facts that do indeed make it seem that a God who operates by intervening would not do things in this way.

Evolutionists note, says Hunter, that countless species have thrived for millions of years but then have been wiped out by changes in climate or by some natural disaster, many of them seeming to have left no descendants at all. Undirected natural process would make sense of this. Would an Omniscient Designer do things this way? Many organisms do not seem well designed in the first place. Humans share in the limited mammalian eye, whose neurons from the cells in the retina run across the top of those cells, obscuring vision. The eyes of raptors (hawks, eagles) are much better “designed.” The human spinal cord is an awkward and trouble-prone adaptation of a vertebrate structure that works well for quadrupeds and even knuckle walkers like chimpanzees. The human appendix contributes relatively little but can kill a person if it becomes infected. An undirected evolutionary process would produce results like this. Would a Divine Designer do things this way? The DNA package has a great many hitchhiker genes, along for the ride but doing little. A random process of evolution would explain this. But would a Designer do things like this? These are theological questions, Hunter insists, not biological. If evolutionary theory is built upon metaphysics or theology, then it should be excluded from science classrooms. Ironically, as the reader may have noticed, Hunter’s discussion of the theologizing done by evolutionists elaborates a great amount of the evidence that makes evolution look like a natural and undirected process.

There is much else to say about ID and its proponents and critics, too much for these brief pages. This is a topic on which use of google.com yields an enormous amount of information.

MORE RESOURCES ON EVOLUTION.

Evolution
Darwin, The Norton Anthology.
(selections from Origin of Species, The Descent of Man, and other writings, along with some later and current commentary).
Bowler, Peter J. Evolution, The History of an Idea. U.Cal., 1984.
A thorough readable account of the history before, during, and after Darwin, in 412 pp. Provides specifics with diagrams of theories of Buffon, Hutton, social Darwinism, and recent debates on punctuated equilibrium.
Bruce Wilshire, Romanticism and Evolution: The Nineteenth Century (NY: G.P.Putnam's Sons, 1968)
Clark R. Chapman and David Morrison, Cosmic Catastrophes (NY: plenum Press, 1990)
A summary of various catastrophes: geological, climatic, astronomical; implications about how dangerous and mindless nature is.
Richard Fortey, Life: A Natural History of the First Four Billion Years of Life on Earth NY: Alfred Knopf, 1997).

Evolution and Religion
Dobzhansky, Theodosius, The Biology of Ultimate Concern (NY: New American Library, 1967).
Chapters on "Humanism and Humanity"[and science], "On God of the Gaps"[and the drive of science to understand all, with vitalism as an e.g.], "Evolution and Transcendence"[and determinism, etc.], "Self-Awareness and Death-Awareness"[the problem of being conscious of life and limit], "Search for Meaning" and "The Teilhardian Synthesis"[criticized]. Clearly written.
Robert Jastrow, Until the Sun Dies (W.W.Norton, 1977)
Brief popular and clear account of the evolution of the physical universe from big bang through development of planet and beginning of life, and possibility of other life in the universe.
Ernan McMullin, ed., Evolution and Creation (University of Notre Dame, 1985).
His introductory article gives interesting background about the history of Christian beliefs, from Augustine up to Darwin.
Mary Midgley, Evolution as a Religion (NY Methuen, 1985)
Criticizes evolutionary thought as a worldview that has justified Spencer's rugged individualism and perpetuates the Enlightenment atomistic individualism. Cites Monod, Dawkins, and Wilson to attack their perspective which says we are all part of an aimless world (Monod) in which we are programmed to be selfish (sociobiology).
Gerd Theissen, Biblical Faith: An Evolutionary Approach (Fortress, 1985)
Interprets the evolution of Judaic and then Christian religion, as seen in the biblical process, as the evolution of cultural ideals of cooperation (love) out of the harshly competitive context of biological evolution.

Young Earth Creationism: those in favor of it
D. T. Gish, Evolution, The Fossils Say No (San Diego, 1979).
H. M. Morris, The Scientific Case for Creation (San Diego, 1977).
These two have been the leaders of the “scientific creationism” movement. These two books represent their general position and the kind of evidence and analysis they bring to bear.
Thomas F. Heinze, The Creation vs. Evolution Handbook (Baker Book House, 1972).
An evolution-refuter's handbook saying vestigial organs and radiocarbon dating and many other things are not good evidence for evolution, that the law of thermodynamics, paleontologists errors., etc., support creationism.
Pattle P. T. Pun, Evolution: Nature and Scripture in Conflict (Zondervan, 1982).

Creationism: those against it
Laurie R. Godfrey, ed., Scientists Confront Creationism (W. W. Norton, 1983).
An excellent selection of articles on aspects of science related to the creationists' claims, written clearly, by experts. If you have not read much of the creationists' materials, all this heavy science will seem a little overdone. But creationists find many odd lines of argument.
R. M. Frye, ed., Is God a Creationist? (New York, 1983).
This provides an excellent set of articles by experts who write well. Their conclusion is that God is not a creationist. (The articles, unfortunately, have relatively little documentation.)
Dorothy Nelkin, The Creation Controversy (W. W. Norton, 1982).
A very good report, written quite clearly, covering a variety of aspects including the historical background from the nineteenth century up to recent years, religious issues involved, the attempts to upgrade the teaching of biology, court cases, etc.

Intelligent Design: proponents
Phillip E. Johnson, Defeating Darwinism by Opening Minds (1997)
In addition to the 3 books named in the chapter, a shorter introduction to Johnson’s arguments and style.
William Dembski, Intelligent Design: The Bridge Between Science and Theology
(InterVarsity Press, 1999). Dembski is the main theoretician of ID. An earlier book, The Design Inference provides the basis for these two. A book Dembski edited, Mere Creation: Science, Faith & Intelligent Design (InterVarsity Press, 1998), contains articles by many different supports of ID.
Some URLs
to get a sense of the complexity of the fossil record and the enormous number of branching families of organisms, go to the Tree of Life at http://tolweb.org/tree/phylogeny.html
Pros and cons on Dembski can be found at http://www.nctimes.com/~mark/bibl_science/dembski.htm
National Center for Science Education has numerous links to those criticla of Dembski http://www.ncseweb.org
Dembski’s main sponsor can be found at http://www.discovery.org/csrc
Jonathan Well’s book, Icons of Evolution has been popular among ID proponents. For a chapter by chapter critique try,http://www.talkorigins.org/faqs/wells
For Support for Wells : http://www.ncseweb.org tp://www.arn.org/wells/jwhome.htm
A quick critique of Behe: http://bostonreview.mit.edu/br21.6/orr.html