Some Non-Scientific Observations on the Importance of Darwin

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1 1 of 14 9/17/2015 5:20 AM Answers in Genesis Home of the new Answers Magazine! Ads by Goooooogle The Hand of Darwin View high-res images of Darwin's private notebooks and watercolors speakingoffaith.org Transform Your Beliefs You Can Change Your Limited Beliefs And Get The Life You Truly Desire. God loves you God loves you and has A wonderful plan for your life Advertise on this site Some Non-Scientific Observations on the Importance of Darwin Ian Johnston Liberal Studies Department Malaspina-University College, Nanaimo, BC [The following is the text of a lecture given, in part, to a group of senior Biology students at Malaspina University-College, Nanaimo, on October 1, The text was very slightly revised in October This document is in the public domain, released October 1998] For comments or questions, please contact Ian Johnston. A. Introduction Good afternoon. You will have to forgive me if I look a little nervous. However, it is not everyday that I venture into a hotbed of revolutionary radicals bent on overthrowing all traditional forms of order, young followers of the most disturbing intellectual upheaval that our culture has ever gone through, spirits dedicated to a cause that has produced a belief system that has undercut all forms of stability, order, and customary belief. You do look friendly enough, but I must warn you that I'm on my guard. My study of the subject you have committed your professional selves to has taught me to be very careful of biologists, even when they bear gifts. Today, I would like to explain to you why I have such apprehension, why, that is, biology has proven to be such a revolutionary activity, why I can, with good justification make the claim that no single event in the history of our culture has had such a devastating effect on our political, intellectual, religious, and moral life as has the development of the modern understanding of the world given to us by biologists. I suspect that some of you may at this stage find those claims somewhat exaggerated. They are not, and I hope to persuade you that I am right in characterizing biology in this way. In order to do that I am going to have to discuss a number of aspects of the history of your discipline, that is, to acquaint you with some of the features which make modern biology something which has shaken everything that went before to the foundations. In order to do that I am going to have to talk about Charles Darwin, and if you know no history of your subject, you should at least carve onto the front of your notebook the figure 1859, the year Darwin published Origin of Species, the year he dropped the bombshell which we are still trying to deal with. My concern here is not going to be scientific, although I shall have to discuss scientific ideas and achievement from time to time. My main concern here is to explore the wider consequences of Darwin's ideas, as these manifest themselves in philosophy, religion, politics, morality, and in knowledge generally. In doing this, I am not simply seeking to provide you a lot of background information or pleasant details which will supplement your scientific studies; I am trying to do something much more than that: to acquaint you with a problem you are going to have to deal with as professional biologists. To make this last point clear, let me put on the table some curious facts of the modern world. You may be familiar with them, but if you are not, then you are soon going to be. 1. First, Darwin's general theory has become, in association with the development of genetic theories, the

2 2 of 14 9/17/2015 5:20 AM orthodoxy in biology. Of course there are many vigorous disputes about the details (e.g., the arguments between, say, Dawkins and Gould, the debates about the sociobiology of Wilson and others) and there are many issues still to be ironed out. Still, it is virtually impossible to be a practicing biologists anywhere in the world without subscribing to Darwin's theory of natural selection Secondly, Darwin's theory is, of all the great scientific theories, the easiest for anyone to understand. Any lay person who can read has immediate access to what Darwin is saying, in a manner that is simply not possible with the theories of, say, Newton or Einstein or Bohr. Finally, in spite of this total dominance of the scientific community and its ready accessibility, Darwin's theory is totally rejected by approximately half of the population in North America, one of the best educated and most scientifically sophisticated societies the world has ever seen. People have no trouble accepting Newton or Einstein; there is, by contrast, enormous hostility to Darwin. It might interest you to know that Darwin himself seems to have had profound unconscious worries about the consequences of his own theory. He suffered, as you may know, for most of his life from a mysterious and very debilitating condition which made his work difficult to carry out. No one has successfully defined what disease afflicted him, but a number of biographers have come to the conclusion that it was probably psychosomatic, a deep psychological distress at the recognition of what the full implications of his theory might mean. In fact, this worry was clearly an important factor in his decision to delay publishing his theory for almost fifteen years; he finally was forced to go public when another natural scientist, Wallace, came up with the same idea. This problem of the prejudice against a central tenet of biological theory should concern you as would-be professional biologists, and it is far too simple to write that rejection of Darwin off as the result of ignorance or simple religious prejudice (although that may well be the case with many people). The fact is that what Darwin did in 1859 was the most revolutionary act in our intellectual history, and millions of people still find the consequences unsettling and unacceptable. I am going to attempt to tell you why. I welcome the chance to do that because I would like you all to understand that Darwin's theory is intellectual dynamite. You are, I assume, familiar enough with the theory as an organizing principle in modern science. But if that's all you understand about Darwin, then you will be very ill equipped to understand the full implications of his achievement and, beyond that, the widespread distrust and active hostility which his theory still encounters and will continue to encounter. As I have mentioned before, no idea in the history of our culture has such revolutionary implications. It is no accident that Karl Marx wanted to dedicate his masterpiece to Darwin or that the destroyer of all philosophical systems, Friedrich Nietzsche, owed such an enormous debt to the work of this quiet, middle-class, mildly liberal English naturalist. To substantiate these claims, I'm going to tell you a story, one you are probably not all that familiar with. In Liberal Studies a colleague of mine (who is a scientist) likes to say that for modern scientists the story of biology begins with Darwin but that the truth is that with Darwin the story ends. By that he obviously does not mean that there have been no exciting or important advances in biology since Darwin; he does mean that all of those are essentially developments of or refinements to what Darwin achieved. The really exciting period, the truly dramatic and revolutionary story, is the period up to Darwin. He is the fifth act of the drama, as I hope to demonstrate to you. B. Some Terminology: Biologists and Darwin However, before we begin that story, I'd like to clarify a couple of terms. I began by making all sorts of allegations about biologists. But the story I am going to tell was conducted largely by people who did not call themselves that. The terms biology and biologist (which were coined by an unjustly maligned scientist of major importance, Jean-Baptiste Lamarck), after all, are not yet two hundred years old. The people I am going to be talking about thought of themselves, for the most part, as natural scientists, as philosophers with an interest in the natural world, as people of God looking for evidence of His work in the natural world. They did not live in a world where knowledge about the world was so neatly divided into disciplinary components and they moved easily between religion, philosophy, politics, and natural science because they saw these as all inextricably interconnected. Many of them, in fact, took up natural science or encouraged it in order to further their religious or political beliefs. So I will be using the word natural scientist rather than biologist--not as any insult to people here present, but simply to remind us all that the stern and strictly organized discipline suggested by that word biology did not exist in the period I shall be talking about. Secondly, I want to clarify what I mean by Darwin. Of course, I refer the man Charles Darwin, but I also mean all the things that made his work possible. One of the great problems with a major scientific theory, like

3 3 of 14 9/17/2015 5:20 AM Darwin's or Newton's, is that it tends to get all the credit. It throws into an eternal obscurity the vital work that other natural scientists carried out which made the great achievement possible. I think it's probably fair to say that hardly any major scientific discoveries or theories are carried out in isolation by a single imagination. They are the result of a wonderfully synthetic imagination which gathers together into a coherent form the work of a many predecessors and contemporaries. That is certainly the case with the two most impressive theories of the modern age, those of Newton and Darwin. And the power and influence of these theories have encouraged us to forget (or at least to fail to remember) the many great natural scientists without whose work the theories would never have appeared. It may be worth remembering that when Darwin published his theory, Thomas Huxley was staggered at the simplicity and obviousness of what Darwin was proposing; the intellectual climate, which others had prepared, had made, in his view, Darwin's theory inevitable. However, in celebrating the greatness of Darwin, we often lose sight of those others. Anyway, when I use the term Darwin and Darwinism, I would like to include in that a sense of all those others who contributed (sometimes by their opposition) to furthering the intellectual movement which made Darwin's theory possible. C. The Revolutionary Basis for Biology: Classification In order to grasp why Darwin's theory was so fundamentally revolutionary, you must understand one intellectual concept: the power and importance of classification systems. As students of biology you are thoroughly familiar with the need for classification, at least within your discipline. But I want you to step back from the discipline for a moment to understand the importance of classification in general. It will be obvious enough to you, as biologists, that you cannot function in this discipline without a comprehensive system of classification. This is especially the case with biology, and has always been a central issue in this part of natural science, simply because in biology, more than in any other science, there is a huge variety of natural phenomena to deal with. But I would argue that systems of classification are essential for all human thought and for the same reasons. Without a classification system of some kind, something which enables us to compartmentalize similar things and to make distinctions between other things, we simply cannot function. Providing us a classification system is the primary function of our education: we learn to classify things in order to make moral distinctions, to establish the hierarchy of goods and goals for our lives, to understand the natural world around us, and in order to function as social beings. How we think is largely determined by how we classify things. The great systems of belief in religion or philosophy or politics are classification systems. Christian belief, for example, encourages me to distinguish between Christians and pagans, between sinners, good people, and saints; a political classification system tells me whom I must or should obey, whom I am responsible for, who owes me allegiance, and who I can ignore. And so on. When I am faced with a problem, I simply cannot begin to analyze it, understand it, and resolve it unless I first have a classification system available for understanding it. The greatest thinkers are not those who come with new answers for old problems. They are the ones who redefine the problem by putting a new classification system on the table. Plato did not solve the problem of how to make people good; but after Plato it was impossible to talk intelligently about good and bad people without bringing knowledge into the discussion. Marx did not solve the social ills of his time; but after Marx it is impossible to discuss social problems without invoking the classification of society into classes based on material wealth. What makes these thinkers revolutionary is that they redirected the discussion and provided a new vocabulary for exploring, understanding, and seeking to resolve human problems. The reason these thinkers focus on classification systems directly is that these systems are never ideologically neutral. The way we organize things into compartments indicates to us an entire network of relationships and hierarchies which are loaded with political and moral value. To take an obvious example. If my moral system requires me to be kind to human beings, then I must attend to what my classification system tells me about who is a human being equal to me. If it indicates, as some have done, that, say, aboriginal people or black people, or the Irish poor are not fully human, then my moral obligations to them are not the same as my obligations to the white middle-class people next door. This may be an extreme example, but it makes the point. And someone who wants me to treat aboriginals, blacks, and the Irish poor as human beings is never going to persuade me until such time as he can overthrow my classification system and replace it with a different one. I want to make you understand Darwin's achievement in this light. His work is the culmination of a massive revolution in our classification systems. If you know anything about the history of biology, you will be familiar

4 4 of 14 9/17/2015 5:20 AM with some of that. But what I want to suggest is that the revolution he brought about, the classification system which he introduced in biology, has immediate implications far beyond the question he sets out to investigate, the origin of species. His masterpiece has only one mention in it of human beings in it, but the implications of the theory, as Darwin understood only too well, are direct and overwhelming. D. The Great Chain of Being Very simply put, Darwin's theory is the culmination of a process which destroyed for ever for us the oldest classification system in our history, the way in which our culture since the Ancient Greeks had understood the world. This system was also a biological classification system, the oldest, most successful and influential system of thinking in our culture: the Great Chain of Being. The Great Chain of Being had its origin in Greek philosophy, particularly in the work of Aristotle. He proposed, as a means of classifying life, what he called the ladder of life. In this scheme, living things were to be arranged on an ascending scale, with a particular natural phenomenon's place determined by its ability to move. Such a scheme sees life as hierarchically organized, some forms of life are more primitive than others, some are more fully developed. Hence, in this scheme there is an applied value judgment. Aristotle's ladder of life was appropriated by Christianity in a combination with a notion from Plato concerning the goodness of God. According to Plato, if God was perfect, then all forms of life must have been created. To leave any potential life unrealized would be a violation of the perfection of the highest power (this idea is called the Principle of Plenitude). Thus, the Great Chain of Being contained in it all the possible forms of life arranged in an ordered hierarchy, from the lowest inanimate forms of life, up through the various stages of plants and animals, then the different ranks of human beings, from slaves and serfs up to the highest forms of humanity, the kings and queens and popes, and then up through the various orders of angels (cherubim and seraphim) right up to God himself. Space itself was organized into the lowest sphere of imperfection (the area below the moon, that is, the earth and earth's atmosphere) and the realm of the perfect heavens (home of the angels and of God himself). What's important to note here is that, although the Great Chain of Being originated and continued to serve as a biological metaphor, a classification system, it was very much more than that. This hierarchy linked everything in the world and beyond to God himself. As an individual part of the chain, I knew my place: I had a responsibility for the things below me on the chain and an obligation to those above me. Since the orbits of the planets coincided with the various orders of angels, the structure of the heavens was linked directly to the hierarchies of life on earth, and all of creation was a single coordinated whole. Hence, with this metaphor my understanding of the world around me and the stars above was inextricably linked to my understanding of my own purpose in life: science and a moral purpose were fused, and hence there was no division at all between my religious understanding and my scientific knowledge. Thus, the Great Chain of Being served as a religious, moral, and political metaphor as well as a classification system in natural science. And this image is so important that it is quite impossible to understand Medieval painting, or Shakespeare's political vision, or Renaissance poetic imagery, or Dante's cosmology without some knowledge of this vision. It is absolutely fundamental to the way our culture understood itself for over two thousand years. It is important to stress two features of this classification system: first, it was complete. There was no room in it for new life. The authority for this was Plato's Principle of Plenitude (that it would be logically impossible for the highest creative Good not to create everything) and the Book of Genesis, which states that God created the animal and plant species in the week of creation. The second important feature was that this hierarchy was static. It was not a mobile staircase. All life was born into its particular place in the hierarchy, and living a moral life, being a worthy animal or person, required one to acknowledge one's position between higher and lower forms and to live according to the duties and responsibilities of that position. The greatest Christian sin was pride, that is, thinking oneself better than one's position. Hence, the political implications of the Great Chain of Being as a classification system are inherently conservative in the sense that it does not admit any possibility for change. Kings are superior beings to normal people. They have a divinely ordained place in the Great Chain of Being which gives them the responsibility for ruling, just as our position gives us the duty of obeying. Everyone on the chain is between higher and lower forms, and the greatest danger to life is to regress to a lower form, especially if that comes in the attempt to move to a higher level. Now, the great attraction of the Great Chain of Being, other than its simplicity and its aesthetically pleasing

5 5 of 14 9/17/2015 5:20 AM design as a series of concentric circles, is that it makes the world morally and physically intelligible. It tells me who I am, where I belong, and, most important, what I must do. It is a classification system which links me intimately with all creation and indicates to me how I ought to live my life. Beyond that, it constantly informs me of God's continuing care for me and the world, because in seeing the hierarchies of being all around me, either in the social structure or in the nature or in the motions of the planets, I see evidence for his benevolent design. God is present in the world; I know that because I can see the wonderful design of the Great Chain of Being everywhere in it. E. Those Disturbing Astronomers The first major challenge to the Great Chain of Being came from the astronomers, who upset the traditional scheme by proposing, with Copernicus, that the cosmos should have the sun at the centre rather than the earth. There is not time here to review the stages of this dispute, but I do want to point out why so many people objected. Everyone has heard about the trouble Galileo got himself into by seeking to further Copernicus's model of the cosmos, and a simplistic criticism is often directed against the inquisitors as simply power hungry, bigoted, ignorant churchmen. Some of them may have been. But let me propose something a little more sophisticated. The objection to Galileo also came from people who recognized what would happen if the Great Chain of Being classification system was cast aside. If the universe was really, as Galileo proposed, all simply governed by the same laws of motion everywhere, without the separate moral spheres, then people's understanding of the world might lose much of its moral meaning. They would cease to be linked so intimately with all elements of creation and with God himself. In other words, they were objecting to the erosion of morality from our classification system. However, for a number of reasons too complex to enter into here, the trend initiated by Copernicus prevailed and culminated in the publication of Newton's Principia, in which he proposed a mathematically accurate model for understanding the solar system with the sun at one of the focal point of the elliptical orbits of the planets. But although Newton's model required a massive rethinking of the Great Chain of Being, his sun-centred model still kept the main ingredients of that system vital for three main reasons. 1. First the mathematical precision of Newton's model seemed to demonstrate beyond doubt that God had organized His creation with a precise design. Hence, we could strengthen our faith in God by contemplating the wonderful mathematical regularity of His creation, as demonstrated by Newton. And throughout the eighteenth century the major defence against the godless revolutionary biologists was an appeal to the divine design demonstrated by Newton. 2. Second, although some of the implications of Newton's model were disturbing (especially the immense spaces which it required, an unimaginable expansion of the friendly dimensions of traditional astronomy), nothing in it directly contradicted the Genesis account. 3. Thirdly, and as we shall see, most importantly, Newton made no attempt to expand his theory into an account of how the cosmos reached this present arrangement. In fact, he expressly repudiated any mechanical explanation for the development of the heavens. In his view, God had established the heavens in the way Newton's theory described them, and nothing could possibly alter that other than the direct intervention of God himself. Hence, in Newton's theory, the structure of the cosmos was as static and divinely ordained as the Great Chain of Being. F. Static Classification Systems But the relative stability promised by Newton's model of the universe was only one aspect of the challenge to conventional ways of thinking about the world. For natural scientists looking at plants and animals were facing something of a crisis during the seventeenth century, a development brought about by the discovery of new species through overseas exploration, technical improvements in lenses which led to the discovery of the microscope, and the growing interest in what we call biology. In 1600, for example, about 6000 plant species had been discovered; by ,000 more were known. This was putting enormous pressure on traditional systems of classification. This rapid proliferation of primary phenomena led in the late seventeenth and early eighteenth centuries to a marked interest in new classification systems for plants and animals. Again, there is not time here to go into the details, but you should know that the this trend culminated in what has come to be hailed as the first great work of modern biology, something which has shaped your own studies decisively, that is, the classification system of the great Swedish natural scientists, Carl Linnaeus. In his System of Nature, published in 1735, he assigned a descriptive place in a comprehensive classification system to every known animal and plant. To do

6 6 of 14 9/17/2015 5:20 AM this, he created the binomial system of nomenclature still in use and the breakdown of the organic structures into Classes, Orders, Genera, Species, and Varieties. Linnaeus, however, did not break with the tradition of the Great Chain of Being. For him, species were fixed and eternal. There was no such thing as a new species. He thus saw his descriptive classification not as a human construct fixing the stages of a developing nature but as defining categories established by God at the time of creation. Linnaeus's account of nature, therefore, reinforced and, as it were, updated the traditional hierarchical, static understanding of nature. G. The Design Argument By the end of the seventeenth century and the early eighteenth century, there was a widespread feeling that in the work of Newton the new natural science and religion had been very happily reconciled. The evidence for an elaborate and pleasing design in the universe had been demonstrated by Newton, and such a design for many people clearly demonstrated the existence of a designer, a divine mathematician, without whose active shaping intelligence no such design would have been possible. Linnaeus's work (which was far less well known) had suggested a similar carefully ordered structure for organic beings. This design argument is vital to understand. Modern science, on the Newtonian model, explained natural phenomena on mechanical principles. That is, it focused on how things work, using mechanical models and mathematical formula (the standard image was that of the universe operating like a perfect clock). It does not take into account any sense of moral purpose (which was the basis of the old science). In fact, modern science had started in the work of Galileo and Bacon, among others, with the insistence that secondary causes (the mechanical processes of cause and effect) were the true work of the natural scientist and that first causes (the moral understanding of the purposes of things) should not enter into scientific explanations. In that sense, science could be seen as being hostile to religion: it divorced explanations of natural things from moral or divine purposes. However, the design argument could overcome this problem. If the mechanical model demonstrated some evidence of intricate and regular design, then, so the design argument held, there must have been a designer. Hence, the mathematical regularity of nature, especially Newton's cosmology, could be used to reinforce religious belief. Thus, science was actively encouraged and carried on by devout Christians and many practising clergy as the most important way to promote religious faith. It is quite wrong to think, as many naively assume, that science and religion were natural enemies. That is very far from the case. H. Historical Science But even as many people were celebrating the triumph of natural science as the handmaiden of religion, forces were at work which were to challenge this design argument and, in the culminating experience of Darwin's work, to overthrow, not just the union between science and religion but also, in many people's minds, religion itself. That development we call historical science. The term historical science introduces a new form of understanding phenomena. It refers to the method of seeking to understand a natural phenomenon, not with reference to an eternally fixed classification system (on the model of Linnaean or Newtonian systems), something ordained by God from time immemorial, but rather with reference to a story. A historical approach to explaining something seeks to claim that we can best understand something by describing its origin, development, and perhaps its future direction. The development of historical thinking has a revolutionary impact for one vital reason: by suggesting that something has a story and is not eternally fixed in the form we now find it, the thinker is implicitly denying the possibility that the phenomenon has an eternal stability or, indeed, any stability. Once I start thinking of things as having a history, then I have to deal with the fact that once they were not as they are now and presumably they will not be as they are now at some point in the future. What they are now is simply one stage of an ongoing process. Historical thinking thus tends to undercut all claims to the eternal rightness of anything. Whatever is understood historically potentially has no essence. It is not essentially anything specific, only a series of changes. Or, putting the matter philosophically, a historical way of looking at things suggests that there is not such thing as permanent being, there is only an uninterrupted process of becoming. The political and religious implications of this form of thinking cannot be overestimated. Let me take one example. If I believe in the Great Chain of Being, in the eternally fixed divinely ordained classification system which has arranged things hierarchically, then I will be a strong supporter of the system of government based upon the traditional classes and ways of doing business. That, after all, is ordained by God and is a law of nature. If, on the other hand, I develop a historical imagination, then the present arrangement is not something

7 7 of 14 9/17/2015 5:20 AM permanent, not something eternally underwritten by a Law of God. It is the product of a process. Thus, it can and will be changed. It is going somewhere. Hence, my attitude towards the distribution of power, the value of different parts of the system, and so on will change. These are only temporary stages in the historical development of the state, not eternally valid. Historical science began gradually and was fiercely resisted. I shall be mentioning some features of that development and resistance in a moment. But it is very important to grasp the revolutionary potential of this form of thinking. We are so used to it, that we take it for granted, so that it is difficult for us to imagine a different form of thinking. The fact is, however, that until very recent times, people in western culture, like so many other people in other cultures, have thought of the past and the present as essentially the same. The forces which govern us, divine and secular, are not subject to a progressive process but are permanent features of human life. I. The Geologists And why at this time did historical thinking begin to invade our thinking? The answer to that comes from the rising study of the earth carried on by natural scientists looking closely at the earth (we would now call them geologists). And why were people starting to thinking in a new way about the earth? Well, one reason is that all over Europe in the eighteenth and early nineteenth centuries people were digging canals and building big new cities, and there was growing pressure to come up with some explanations for the curious observations people were starting to make everywhere as they probed the surface layers of the earth. Again, this is a complex subject, but the geologists put onto the table three problems which were very difficult to account for by customary accounts of the creation of the Earth in Genesis or by static classification systems: 1. First, there was the clear evidence of layering in the sedimentary strata of the earth. This strongly suggested two things: (a) that much of the earth now dry land had been formed under water and (b) that there had been a succession of inundations (rather than just a single one). 2. Second, and most important, there was the thorny problem of fossils. How did fossils of sea creatures get into the rocks at the highest elevations? How come many of these fossils had little to no resemblance to known animal and plant species on earth today? Why in many layers were there no human fossils? How could one explain the growing evidence that a number of species seem to have disappeared, to have become extinct? 3. Third, the earth was clearly changing. Under the forces of erosion, of alluvial deposits (e.g., at river deltas), of volcanic eruptions, and so on, even in historical time things were rapidly altering. Cities once at the edge of the sea were now miles inland; certain villages in Egypt were now buried in the sand. The Nile Delta had clearly changed. How could such environmental changes be reconciled with a static, eternally unchanging view of the natural world, especially since it was clear that there had always been a close connection between environmental conditions and the sustenance of animal and plant life? As a result of these (and other) questions, a new form of scientific work began to appear, a theory of the earth. These were explanations for how the world had acquired the features the geologists were describing. And such explanations required a narrative, a story, a historical explanation. Such questions could not easily be answered with an eternal mechanical model like Newton's vision of the heavens. The only way to deal with them was to explain how the earth had once been very different and for some reason had changed and was still changing. J. The Book of Genesis Now, a major difficulty here is that Western Christianity is based upon a historical explanation for the creation of the earth and everything in it. The Book of Genesis, in traditional Christian belief, is a historical account. It was not just a convenient myth but a true story of God's creation. And the same is true for the story of the flood. Hence, the first efforts of British geology, in fact one of the first books of modern geology, was written by an Anglican bishop in an attempt to reconcile the Genesis account with mechanical science. Burnet's The Sacred Theory of the Earth ( ) is often maligned as too fanciful and unempirical. By modern standards the science was crude, but the attempt was an honest one, for Burnet insisted that defenders of religion must not fight the new science; it was essential that the two be reconciled. And God would not have given human beings a scientific understanding if the two could not be reconciled. His effort was followed by many others. In fact, publishing theories of the earth became a major literary genre,

8 8 of 14 9/17/2015 5:20 AM and the number of competing theories proliferated to the point where it was difficult to keep track of them. This is one of the great anarchic periods of modern science. Unlike today, there were no institutionalized authorities to rule on what might count as a viable theory and what might not; there was no agreed upon method for what characterized the activity known as natural science. So the richness and variety of scientific theories and the rapidly accumulating empirical data make this one of the most fascinating and exciting periods in the history of science. Gradually, however, three tendencies emerged, as in all revolutionary situations. There was the old guard, those who wanted to hang onto the traditional notions at all costs. These were natural scientists who strove to maintain the fixity of species, the unchanging nature of the earth, the denial of a historical development over time. At the other extreme were those with a growing interest in historical development without regard to traditional views of the Book of Genesis. These people were increasingly flirting with the idea of some evolutionary development, that is, the development of new species out of the transformation of old species by some as yet unknown process (such ideas were growing increasingly common by the second half of the eighteenth century). In the middle were the moderates: those who were growing increasingly convinced of some historical development but who strove to reconcile such an account with traditional religion and with interpretations of the Genesis account. K. The Political and Religious Dimensions of this Scientific Conflict None of the major players in these disputes carried on his work in isolation from a host of non-scientific questions, for the political and religious implications of scientific theories were of major concern. To defend the fixity of species and the lack of a historical development was, obviously enough, to insist on an agenda of traditional stability. If the classification systems of nature were eternally fixed in accordance with known compartments or laws, then it was wrong to talk about developmental change. By contrast, to talk of historical development was to undermine the legitimacy of the present order of things; it was to suggest very strongly that change in the biological world might endorse change in the political world. What made these debates all the more vital in the second half of the eighteenth century and well into the nineteenth was that Europe was going through another crisis, and a biological one at that. The population was exploding. In fifty years the population of Europe doubled; then it doubled again; and then it doubled again. Under the pressure of the industrial revolution huge new cities were developing. Communities which had been sleepy agricultural villages became huge industrial cities in a generation. Everyone could see around them what was happening, but lacking any statistical or census data, no one could understand the full dimensions of the problem, and no one knew why this was happening (historians are still debating the causes). As a result of this enormous demographic dislocation poverty was becoming a massive problem and a new social threat was clearly developing: the urban mob, massive numbers of anonymous, frequently rebellious, chronically poor and hungry, often transient citizens. Throughout the late eighteenth century and the early nineteenth century the political tensions of this transformation of European society were everywhere. The pressure to introduce political reforms was increasingly urgent. And scientific theories were introduced and measured against this political agenda. Theories suggesting historical change as the basis for science were, as one might expect, welcomed by the reformers; theories denying the validity of historical change were, as one might expect, endorsed by conservatives. Hence, concepts of evolution of some kind attracted a following among radical and reform circles (Charles Darwin's grandfather, Erasmus Darwin, was an early advocate). The climate changed dramatically in 1789, with the outbreak of the French revolution, in which the urban masses overthrew the old order, massacred the royal family and set up a republican government. This created an enormous panic among other European states and made any proposals for change immediately suspect. Hence, scientific theories which were quite acceptable among reforming circles before 1789 became treasonous afterwards. The growing interest in evolution became associated with godless French science, and anyone advocating it could bid farewell to a professional career as a natural scientist, doctor, or teacher. The extraordinarily hostile climate for historical biology in the years in which Darwin was growing up can only be understood in the context of this political climate. L. Evolution And yet in the one hundred years before the publication of Darwin's book the evidence for some form of evolution was becoming overwhelming. The argument in support of this concept is very simple and totally persuasive. Let me review it for you.

9 9 of 14 9/17/2015 5:20 AM The case for evolution begins with an obvious truth which no sane person can deny, namely, that there is variety in the animal and plant world. The second point in the argument is that all living creatures must have a living parent. This was by no means clear in the eighteenth century (the question was not finally resolved until Louis Pasteur, the great nineteenth-century French biologist, solved the problem of fermentation), but increasing numbers of people were ceasing to believe in spontaneous generation of life from non-life (one of the most ancient beliefs going right back to ancient times). The third point establishing the truth of evolution was the growing evidence that some animals had existed on earth long before the present animal population. The conclusion to this argument was inescapable: the later animals must have developed out of the earlier animals, with some significant morphological change (i.e., evolution). No question was more vital in the arguments about evolution than fossils, and it was becoming increasingly difficult to maintain the idea of the eternal fixity of species in light of all the bones people were digging out of the earth. And so the conservative anti-evolutionary forces changed shifted their ground and began interpreting Genesis as something not entirely literal. Yes, indeed, there had been different ages to the earth. The Genesis account was the story of the last of these changes, and the days of creation should not be considered literally. They were different time spans. Such a view enabled people to account for the evidence for extinction and for the successive layering of the rock strata of the earth without making any concessions to evolution. The history of the earth is thus a history of God's successive interventions, which constituted a series of disasters, Noah's Flood being the last in the series. These theories are now given the general name of Catastrophe Theories or Catastrophism. Opposing the Catastrophists were a group with a growing interest in what has become a fundamental principle of modern historical science, something I am sure you all subscribe to, although you may not be aware of it. This is the principle of uniformitarianism, the key assumption that we can only deal with a scientific narrative by assuming that the forces at work in the world around us today are exactly the same as the forces which have always been at work. Moreover, these forces have always operated at the same rate. Hence, the chief business of historical science, that is, accounting for the process of earth and the development of life, must begin by explaining everything in terms of present processes. The uniformitarians had one huge problem to overcome, namely the issue of time. It took no great knowledge of natural processes to realize that if existing land forms, like, say, the Grand Canyon, had been produced by the same processes as we could now observe, then these processes must have been going on for millions and millions of years, for a length of time almost inconceivable in a culture which had always been used to thinking of the age of the earth in terms of thousands of years (this was and still remains an important objection to Darwin's account). One of the great advantages of Catastrophism was that it could remove this difficulty by arguing for sudden, inexplicable and divinely ordained, catastrophic interventions. The problem for them, of course, was explaining such processes. A key figure in the Catastrophist cause was the great French palaeontologist Georges Cuvier in the early nineteenth century. No one did more than he did to link the classification of fossils to the different rock strata and to insist that the real business of biology was comparative anatomy linked to geology, so that we could gain an accurate understanding of the temporal sequence of species. But Cuvier adamantly opposed evolution and argued strongly against setting any enormous length of time for the present development of the earth. There was, he argued, no evidence for either, and it was impossible for gradual change to occur because an animal was such a highly organized complex interconnection that any change in one part would require the immediate transformation of all other parts. Looking at the present state of the earth, Cuvier concluded that the last great catastrophe must have taken place about 5000 years ago, a time very close to the time indicated by Genesis for Noah's Flood. M. Containing Evolution As the evidence for evolution accumulated (largely through fossils and a growing understanding of the layers of the earth), traditional opponents made concessions to the idea. Two prominent strategies for holding the full implications of evolution at bay emerged. The first was to concede that the earth was subject to constant change and was not static, but to propose that the change was cyclical. Thus, there was a permanent unchanging pattern by which the earth worked, and the changes we could see were like the orbits of the planets, phases in an eternally recurring cycle. Of course, the time periods were immensely longer than for the planetary orbits, but essentially there was a constant pattern. This idea informs the first great work of British geology, James Hutton's Theory of the Earth, in which he proposed the rock cycle, a process by which rocks were eroded, broken down, and carried off into the sea where they formed sedimentary layers. Under pressure and heat in the depths the rocks reformed and emerged

10 10 of 14 9/17/2015 5:20 AM from the molten material to form new rocks and thus to complete the cycle. Hence, there was, amid the change, an eternal permanence in the pattern of the cycle. The second strategy to contain evolution was to concede that some species change was possible, but that it was limited within groups. Thus, while there might be some development in the group of, say, mammals, there was no movement from one major group to another (e.g., from reptiles to mammals). Thus, evolution is a limited phenomenon and not the ruling principle of nature. [This latter position, a favourite of conservative biologists by the end of the 18 th century was challenged seriously by the arrival on the scene of a duck-billed platypus, which seemed a new species clearly intermediate between reptiles and mammals and which was hailed by the radical biologists as evidence for a thoroughgoing evolutionary principle across major divisions. A furious intellectual, anatomical, religious, and political fight ensued (with the Royal Navy under orders to keep the supply of specimens, all from Australia, out of the hands of French scientists). It concluded with a victory for the conservatives, led by Owen, the well known British anatomist who classified the species as a variety of mammal. The establishment was so delighted with Owen's work in this fight against the French that they promoted him to the Royal Society]. A third strategy to contain evolution was to see it guided by divine processes and thus quite reconcilable with religious feeling (although not, perhaps, with Genesis). Hence, change was a progressive manifestation of God's love for humanity. This idea could easily be adapted to secular visions of progress without the guiding presence of God (for example, by seeing in the history of life a progressive moral improvement in animal life, a direction aiming at a much higher form over time). N. Lamarck It was a colleague of Cuvier's, Jean-Baptiste Lamarck, who first put on the table a full blown scientific theory of evolution in Lamarck endorsed the hierarchy of being, the scale of nature, but for him it was a moving and progressive hierarchy. Organic forms could produce significantly different offspring by developing in themselves different characteristics. The driving agent of morphological change was the environment and habit (something Erasmus Darwin had also proposed). The divisions biologists had created to divide off one species from another were, Lamarck proposed, arbitrary aids to memory, not eternally fixed divinely ordained categories. To demonstrate this, Lamarck paid great attention to invertebrates, pointing out that there were not nearly enough categories for them in existing systems of classification and proposing the addition of a number of new categories (multiplying the categories significantly reduces the differences between those animals on the ends of the classification system and puts pressure on the biologist to see how one species could merge or run into another). For Lamarck evolution was progressive (leading to better forms of life) and could be restarted at any time, since he believed in spontaneous generation of life from non-living matter. Lamarck's theory received a very hostile reception, especially in England. Conservatives everywhere, including his eminent colleague Cuvier derided him. He died in obscurity and poverty, and history has been unkind to him by forgetting the boldness of his evolutionary scheme and castigating him for his enthusiastic endorsement of the inheritance of acquired characteristics (something Darwin also subscribed to). Even Darwin, normally a polite controversialist, seems to have slighted Lamarck. But Lamarck deserves an honoured place in the history of biology (a term he invented), and if as a result of this talk some of you become a little curious about reading what he had to say, then this talk will have achieved something important. O. Darwin At this stage you might well be starting to ask yourself what was so special about Darwin. If evolution had been around in some form or another for about one hundred years before Darwin, and if Lamarck had published a fully fledged comprehensive theory of evolution fifty years before the publication of Origin of Species, then why was Darwin such a revolutionary? It's clear the effect of his work does not depend on a new theory of inheritance (Darwin's notion of inheritance was a grave defect in his theory, since the "blending" process he proposed would have made his theory impossible), and he subscribed as firmly to the inheritance of acquired characteristics as Lamarck. So what was the big deal? He offered no major new discoveries of amazing species or fossils (as Cuvier had done), so why is he considered such a vital contribution? Darwin's importance comes from this central idea: the process which drives evolution is essentially random and linear. In Darwin's theory, variations are produced by some as yet unknown process, and life is preserved or goes under on the simple and brutal principle of survival of the fittest. The development of particular forms of life in all its forms (including human life) is thus to be understood, not as evidence of divine design, but as the accidental by-products of a process that never had them in mind in the first place. And this holds for