With a recent address by Pope John Paul II to the Pontifical Academy of Sciences acknowledging the validity of the scientific viewpoint on evolution, the Catholic Church has begun to officially come to terms with Darwin, just as it had done with Galileo a few years ago. Fortunately Charles Darwin lived and wrote in more enlightened times than those of Galileo, and the Catholic Church it would seem has less to answer for in his case.
While definitively cautioning against the literal description of the scriptures, the Pope nevertheless emphasised the equal validity of spritual and other ``interpretations'' of evolution, making a distinction between scientific observation and theory. Man and his ``spirit'' remain an arena special to religion.
This action of the Catholic Church, in its grudging admission of Darwin while seeking to safeguard esssential aspects of its claim to defining the nature of man, highlights one of the deepest philosophical forced by the rapid and constant advance of science especially in this century.
As never before, science today challenges all religious belief. It challenges belief in the existence of a interventionist God, who cares about human affairs; it challenges belief in the existence of any divine plan behind the structure of the universe and it challenges belief in the existence of any special role in nature for living beings with consciousness.
This is not to deny, of course, that atheism as a philosphical current, albeit in a minority, has always existed alongside religion in history. But modern science has converted into concrete theoretical and experimental questions several of the most contentious issues in the debate between atheism and religion, and has provided a factual basis to atheism's philosophical and logical arguments.
To be sure it is not that all that science achieves disturbs the believer, however important such achievements may be to science itself or to the development of technology. There is, after all, nothing offensive about television sets, computers or superconductivity. The real challenge is posed only when science in its pursuit of the goal of the explanation of natural phenomena in terms of a simple set of underlying laws provides answers about deep questions like the origin and nature of life or the origin of the cosmos.
The first great "demystification", as Steven Weinberg describes it, began with our understanding of the heavens. Starting with Copernicus and Galileo science has done away with the idea that the physical location of man was in any way special. Newton's work that showed that the same laws apply to falling bodies on earth as well as the motion of the planets was another great step forward. Today modern cosmology and high-energy physics have made the search for a "final" theory that unifies all fundamental forces and the study of the origins of the universe a subject of theoretical and experimental study and not mere philosophical speculation.
The demystification of life, on the other hand, began with the discovery that chemicals associated with living matter could be synthesised. The next great step was that of Charles Darwin and Russell Wallace who showed how natural selection could explain the evolution of the complexity of life as we know it on Earth today. The theory of evolution thus removed man from any special role in the development of life, placing him in a long continuum of biological evolution.
But even though evolution came to be accepted as a fact and the theory of evolution an accepted part of science, the idea that life and living matter were deeply distinct from non-living matter has taken more time to wither away. But with the development of the understanding of the molecular basis of life, especially with the discovery of the structure of DNA and the genetic code, a severe blow has been delivered to this kind of "vitalism" in science.
In recent times few have done more to drive home these implications of Darwinian theory and the molecular understanding of life than Richard Dawkins. He has also pulled no punches on the way. In a manner comparable to Thomas Huxley, known as Darwin's bulldog in his day, Dawkins has also been a forceful proponent of the view that Darwinism and evolutionary theory leave no room for a God or a creator, and that there is nothing in evolution that points to a "plan" behind Nature.
In his latest book, "River Out of Eden" Dawkins returns to his basic theme, explaining the power of what he refers to as the "Darwinian principle". It is a theme whose several aspects he has explored before, at greater length and far more didactically, in his earlier best-sellers "The Selfish Gene" and "The Blind Watchmaker". But in this relatively short, powerfully written book, Dawkins puts it all together in one connected story, that begins with the origins of life on Earth and ends with an attempt at placing it in an extraterrestrial context.
Dawkins begins by pointing out the elegant economy of assumptions underlying modern Darwinian theory. All that is needed for life to begin, is the production of molecules that have the ability to make copies of themselves, including the replication of the occassional flaws that may arise in this process. What follows from this is Darwinian selection, that eventually leads to "the baroque extravaganza" of life as we see it on Earth today.
The first two chapters of the book lay out the basics of evolution, using in an important way the analogy with digital information theory. Indeed it is more than analogy. The digital nature of the genetic code, Dawkins emphasises, is essential to the fact that genes can copy themselves over several generations with remarkable accuracy, except for occassional mutations, that natural selection either weeds out or preserves. Dawkins points out that evolution is like a flow of genes and DNA through time, the "river" of the title of the book, that slowly branches out into the vast number of variations that are seen today. It is the flow of genes through time that Dawkins emphasises is the fundamental fact of evolution and not the evolution of bodies. Bodies are the vehicles by which these replicators propogate; they provide the environment in which a gene survives together with many others.
In an elegant passage, Dawkins traces back the "river" of human genetic material to the most recent common ancestor in the purely female line that all humans living today must have, the "Mitochondrial Eve". It is a story typical of evolutionary biology; a combination of logic and theory, laboratory and field work, and computer experiments that leads to remarkable conclusions. We can continue this tracing back, Dawkins points out, far beyond the point when humans emerged. in a continuous flow that goes back not less than 3000 million years.
Dawkins deals with two major objections to evolution that are inherent in any religious view of life and its evolution. The first, that is closely associated with "creationism", is the denial that complex organisms could evolve out of much simpler structures. A complex organ, so the argument goes, must emerge perfectly the first time around and not by evolution. Most such arguments, Dawkins points out should be dubbed "The Argument of Personal Incredulity"; those rasing the objection usually have given little serious thought to the question, or assume that no answer is available.
Dawkins explains the issue with the example of the evolution of the eye, a favourite example in such arguments and one dealt with by Darwin himself. The eye in nature is by no means perfect and nature has worked out several varieties, which implies that eyes can evolve. But the point also is that evolution proceeds gradually, and it is the accumulation of several small changes which can in fact unerringly give rise to complexity; the probability of one large change hitting the target is in fact virtually non-existent. Dawkins explains in detail a computer experiment that shows that the time required for the eye to evolve is in fact quite short compared to the time scale of evolution.
The second question is the existence of purpose or plan in evolution. Is there a "Why?" to evolution beyond the question of "How?" This question is often answered in theology by pointing to the apparent purposeful design of living creatures and arguing that it speaks of the existence of a Creator who makes this design fit together.
Part of the question was answered by Darwin himself; purposeful design is an illusion and the true reason is natural selection. But Dawkins goes further and argues that the true driving force of evolution is the maximisation of genetic or DNA survival. From the incredible patterns of behaviour seen in the natural world, the only thing that truly explains all of it is the this principle.
It is a theory that Dawkins first laid out in "The Selfish Gene" and elaborated in his major technical work "The Extended Phenotye". Genes, argues Dawkins, are selected by maximising their survival even to the extent of influencing behaviour beyond the bodies in which they are carried. Nature, in fact, is not efficient. And by no means does Nature work towards common welfare, of species or other groupings. Nature seems, in fact, often cruel beyond imagination. If at all there is a sign of co-operation or altruism, or other attributes like beauty and so on, it is because this is the route by which some genes maximise survival. Life, insists Dawkins, is not governed at the level of operation of evolutionary theory by any goal or purpose.
Dawkins makes no concessions to the philosophically faint-hearted. Nor does he temper his words, in the manner of Stephen Gould, with statements that true science and religion are not in conflict. Dawkins is not a genetic determinist. Nor does he believe that the human society should be run on Darwinian lines. In rejecting any moral or ethical lessons from Nature, Dawkins does not imply a philosphy of moral nilhilism. All this he said elsewhere, at length. But in "River out of Eden", shorn of all these extras, he explains how Nature works.
Small wonder then, that Dawkins figures in a major way in "God, Chance and Necessity" by Keith Ward, who seeks to argue that modern scientific developments, particularly in cosmology and evolutionary biology, have not rendered the idea of God wrong or unnecessary.
The book is quick to make the point at the outset that what is at issue is not the content of scientific investigations. All theists he affirms should support the spirit of enquiry of science. He is even prepared to agree in principle that science can only proceed from the assumption that all of nature is knowable.
But what Ward takes issue with is the conclusion of several scientists that the results of science do not produce any evidence at all for the existence of God or any intrinsic purpose or plan behind Nature as we know it through science.
Ward lays out his position clearly in a chapter titled "The Metaphysics of Theism". It is essential to religious belief that there exist a supreme, perfect Creator, which implies that the universe be intelligible, morally ordered and goal directed. Secondly, theism, according to Ward, provides a over-arching explanation of the existence of the universe and natural laws and is the most economical explanation available. Theism does not deny science but only materialism insists Ward. It is only materialism, and not science, that denies that religion is a different path to truth and there is no issue once this is recognised.
Ward takes up two books, ``Creation Revisited'' by P. W. Atkins and ``A Brief History of Space-Time'' by Stephen Hawking in his discussion of cosmology. Both these books, as particularly the one by Atkins makes clear, deal with aspects of cosmology that are still in the realm of scientific speculation and proposals rather than a definite theory. Ward seems completely unaware of this fact.
But apart from this, Ward does not see the essential scientific point that is being made in popular language. It is generally recognised in physics that any theory of quantum gravity, the subject really at issue when you discuss what happens in cosmology at the very earliest times, must eventually involve a breakdown of our current perceptions of the nature of space and time. Nor do anthropocentric models of cosmology, that generally argue that our universe and its laws and the values of its physical constants are singled out by the emergence of intelligent life in it, represent by any means the last word in the subject. They are not even representative of the mainstream view-point. On both these issues Ward is ready to make a choice in his defence of theism, arguing that space and time must have an a priori meaning, assigned by God, and that the purpose of the known universe is the creation of intelligent conscious life.
Ward's last line of defence is mysticism. Despite his initial acceptance with the viewpoint that nature is completely knowable, Ward retreats to postulating a ``cosmic mind beyond speech and utterance , beyond duality and description...'' And `` that mind, from its infinite potency, selects the fundamental laws and limits of this universe,...''.
But Ward is really far more concerned with the implications of evolution. Natural selection is an illuminating idea, he concedes in the beginning, that explains many features of the biological world but no more. But it is not a powerful explanatory principle, he insists, since it has no predictive power and cannot explain the emergence of complex life-forms or beings with consciousness.
The insistence by science, from Darwin onwards, that change at every stage of the evolutionary process is not directed or purposive, but nevertheless leads to complexity through natural selection is one of the key points that Ward objects to. Dawkins' writing is very much at the centre of attack here together with a complete misunderstanding of Dawkins' computer experiments that demonstrate the evolution of complexity.
Ward, it appears finally is actually against the theory of natural selection itself as understood by Darwin and others subsequently. If by natural selection one understands natural selection without any inherent bias towards the emergence of a rational agency, then according to Ward, the hypothesis of theistic design is a equally good contender. Theistic design is the only ``theory'' that can explain the development of complex life-forms with consciousness.
Ward really reintroduces creationism by the back-door, invoking what Dawkins has referred to as ``The Argument of Desing''. A well-known line of argument in theological discussion of evolution, it basically argues that the apparent purposefulness of design in nature implies the existence of a designer. Bodies are not the vehicles of genes, Ward asserts. Genes exist in order to create bodies, bodies in order to create brains and brains exist in order to create consciousness and purpose, and ``with them appear for the first time in the history of the cosmos, values''. It is not even sufficient for Ward, while discussing evolution, to postulate a cosmic being who creates the universe and its laws and then lets it evolve on its own. God must intervene at various stages of the process in a purposive way and evolution is the working out of a life-plan.
Ward shops around in the realm of ``alternate science'' for alternate ``holistic'' approaches to biology, that are not as ``reductionist'' as the Darwinian theory of evolution. He mentions approvingly a suggested theory of top-down causation in evolution whereby the whole influences the nature of its parts; for Ward the whole is readily indentified with God. He also approvingly mentions the Gaia hypothesis of Lovelock, which thinks of the Earth's biosphere as a single living organism, a hypothesis that has no place in a serious scientific discussion of evolutionary biology.
In the entire discussion, Ward, quite apart from taking issue on matters that are scientifically well-understood, misses a basic feature of any successful scientific theory. While no doubt Darwinian theory is basically overwhelmingly successful, there is a clear need to understand and explain many things further and the task is by no means complete. The emergence of consciousness is definitely a major unsolved problem. But to infer from this that ``theism'' is a better explanation, as Ward does, is to miss the point. The task of science is to proceed to eventually explain what is not currently understood, without the invoking of miracles or external spiritual agencies.
It is also clear that Ward in the end fails to maintain the distinction between science and materialism that he claims he would, as he tries to deal with the issues raised by cosmology and evolutionary theory. Theism, it appears, cannot be defended without debating the content of science itself. Theism is falsifiable, insists Ward, and is therefore forced to defend it by attacking specific scientific concepts or aspects of scientific theories.
It is interesting to find that Ward's objections, in the final analysis, have their roots not in the problem of understanding nature but in the question of the origin of ethical values and morality. For Ward, there is a need to have a notion of absolute values, which are God-given. and consequently a need to establish that nature, being created by God, reflects these values. Any suggestion that there is no such lesson to be drawn from nature is completely unacceptable. For then, the notion of a personal, interventionist God is immediately in doubt.
There is an obvious corollary of the scientific conclusion that the working of Nature is not governed by any ``human'' values like truth, beauty or altruism. And that corollary is that notions of ethics and morality and religion itself are in the ultimate analysis constructed by human beings themselves. This is a point that Dawkins and others have made repeatedly and one that Ward steadfastly ignores throughout the book. Despite the initial tone of the book, Ward in the end resorts to the usual cliched argument against atheism of the ``atheism cannot tell us why torturing babies is morally wrong'' variety.
Ward undoubtedy might appear to some as someone different from the Bible-thumping evangelist who demands equal time for ``creationism'' in schools. This perhaps is not wholly untrue, as the distinction between believers like Ward and those of the ``creationism in schools'' variety could be of some utility in practice in the defence of scientific education. But, despite the apparent sophistication of a non-literal reading of the idea of genesis from scriptural texts, there does not really appear in the end any deep philosophical distinction between his arguments and those of the ``creationist'' variety.
One might be tempted to dismiss the debate between science and religion as of marginal importance to science. And to argue that in the realm of ethics and morality the position of a believer is as true or valid as that of anyone else, irrespective of whether he believes in a world ordained by God or not. But in recent times, ethical concerns arising from scientific advances in biology, particularly human biology and the environment, some of which raise questions that do not have easy answers, have shown that such clean separations between the concerns of science and religion are not really possible. It is in this debate perhaps that the contradiction between science and religion becomes particularly sharp. Whether the public response to such questions is to be based on what is scientifically understood about the natural world, or on mistaken, postulated notions about how nature works, is a matter of some importance for the future.