John Polkinghorne at Nobel Conference XXVI

The last third of this century has been marked by a pronounced change in the dialogue between science and religion. Despite the well-publicized battles over so-called scientific creationism, which is neither scientific nor creation, there has been a great deal of serious research and work going on in the field of religion and science, much of it being done in Great Britain. A particularly important role in this development has been played by scientists who have gone on to develop an expertise in the study of religion. For example, at our neighboring institution of Carleton College, Ian Barber, Arthur Peacock, both of whom have spoken at Nobel Conferences, and now John Polkinghorne, who will speak at a conference. John Polkinghorne has capped a distinguished career as a mathematical physicist, which is a subject he has studied for 25 years. He taught at Cambridge University for 21 years. He has capped this career with his ordination as a priest in the Church of England in 1982. He has since served parishes in Cambridge, Bristol, and Blaine, and as dean and chaplain of Trinity Hall at Cambridge. He is now the president of Queen's College at Cambridge. His extensive publications include works on mathematical physics and quantum mechanics. Our Curriculum II course, The Natural World, has used his book, The Quantum World. More recently, he has published extensively in the area of science and religion, including his most recent books, Science and Creation, and Science and Providence. His books have been translated into such languages as Japanese, Portuguese, and Polish. In addition to his scholarly work, he has served an impressive array of committees and councils, including membership on the Nuclear Physics Board and chairing the Committee to Review the Guidance on the Research Use of Fetuses and Fetal Material. He is now a member of the Church of England Doctrine Commission. Please join me in welcoming Dr. John Polkinghorne, who will address us on the topic, Chaos and Cosmos, a Theological Approach. Thank you, I'm very glad to be here. If I were preaching a sermon, I'm not, you'll be glad to know, I'm giving a lecture, but if I were preaching a sermon, I would take as my text, the earth was without form and void, and darkness was upon the face of the deep, and the Spirit of God was moving on the face of the waters, which is the second verse of the first chapter of Genesis. Theologians have been in the chaos business for centuries, but the tohu obohu in the Hebrew, the without form and void, in the English translation, it's not quite the same thing as the mathematical theory of chaos, which is the concern of our conference. And the development of that theory, in the last 20 or 30 years, has been an astonishing enhancement, really, of our imagination, for it has presented us with a picture of a sort of ordered randomness, a sort of structured flexibility present in the process of the world, and that is a very great enhancement of the imagination, which we have already enjoyed, from the talks and from the pictures that have been presented to us already in this conference. Now, it is a commonplace that the dynamical theory of chaos proves to have applications in many branches of science, but it might seem more surprising that it would be of relevance to theology. And the reason that it is of relevance to theology lies in the twin roles that that subject has to fulfill. One role of theology is concerned with intellectual reflection upon the data provided by the religious experience of humankind. And here, theology stands alongside many other forms of rational inquiry into the way things are, alongside science's investigation of the physical world, ethics' investigation of our moral experience, aesthetics' investigation of our experience of beauty. And each of those inquiries has its own domain of data and its own consequent autonomy. Each has a cousinly relation to the others as they seek a rationally motivated understanding of what is going on. And all of them are required, all of them together are required, if we are to do justice to the richly layered world in which we live. Now, theology operating in that mode as a rational form of inquiry into a certain domain of experience is often called systematic theology. It can neither tell science what to think, as the creationists wrongly suppose, but nor can it be told by science what it should think, which is an error that we usually call scientism. Now, valuable and indispensable as these separate rational inquiries undoubtedly are, in my view, they are not enough to satisfy our thirst for understanding. They are looking at different aspects of the world of our experience, but that world is surely one, and we shall not be fully content till we are capable of integrating our views of it. I'm a passionate believer in the unity of knowledge, and so I'm committed to the search for that single view, that integrated view of reality. The search is usually called metaphysics, and if one believes, as I believe, that the reality we experience is being held in being by the will of God, then metaphysics becomes theology in its second role, a role that is sometimes called fundamental theology. If God is the ground of all that is, then theology in this mode will have to try to speak about all that is. It will seek to act as the great integrating discipline, taking the insights provided by the other forms of rational inquiry and aiming to set them within the most profound and comprehensive scheme of understanding that is available. In my book called Science and Creation, I've written about this role, that if theology is to lay claim to its medieval title of the queen of the sciences, that will not be because it is in a position to prescribe the answers to the questions discussed by other disciplines. Not at all. Rather, it will be because it must avail itself of their answers in the conduct of its own inquiry. Theology's true regal status lies in its commitment to seek the deepest possible level of understanding. On this view, those who are seeking understanding through and through, which is a natural instinct for a scientist to pursue, those who are seeking understanding through and through, in my view, are seeking God whether they name him or not. Bernard Lonergan, a Canadian Jesuit, put this with lapidary elegance when he said, God is the unrestricted act of understanding, the eternal rapture glimpsed in every Archimedean cry of Eureka. I like that quotation very much. Now there is, of course, no simple procedure for constructing a metaphysics going beyond, which is what meta means, going beyond science. The tests for the validity of the endeavor will be such things as comprehensiveness and coherence. Every new insight that the separate inquiries of science or systematic theology or ethics and so on can provide will be of value in that task. And I believe that the dynamical theory of chaos in its way can afford us significant help in that quest for an understanding through and through. However, we shall need to have a certain intellectual boldness in the way we proceed. Metaphysicians and theologians, rather like cosmologists, face problems that cannot be tackled without a certain willingness to speculate. A delicate balance is required between enterprise and caution, neither fearing to stick out our intellectual necks a bit, but not doing so to the extent that they become disengaged from the sober body of reliable knowledge. Let me at least start with my head tightly drawn in. The theory of chaos, which I have studied, tells us that those tame systems on which most of us of a certain age cut our dynamical teeth, things like the steadily ticking oscillator or the ceaselessly revolving single planet, such tame systems are quite exceptional. I call them tame because small uncertainties in our knowledge or small disturbances in circumstance only produce for these systems correspondingly limited consequences in their behavior. To all intents and purposes, we can know what they are up to. Yet, most of the physical world, even when we describe it in the apparently dependable terms of classical Newtonian dynamics, is not like that. In Popper's famous phrase, there are many more clouds than clocks around. Once systems attain an even modest degree of complexity, they become subject to an exquisite degree of sensitivity to circumstance that makes them intrinsically unpredictable. Their behavior exhibits apparent haphazardness, but not to an unrestricted degree, which of course is why the theory of chaos is really such an unfortunate and inept name. Rather, one sees a kind of structured randomness, as the speakers of this conference have been and will be describing. Now, I think what I've said so far is unquestionably physics and generally accepted. If I want to make metaphysical and so potentially theological use of that, I shall have to take the risk of moving on to more contentious questions. Now, the surprising feature of classical chaos is that it presents us with apparently random behavior arising from solutions to deterministic equations. It is an oxymoronic sort of subject in that way. Now, the metaphysical question is this. Which should we take the more seriously, the randomness or the determinism? Let me put it this way. The most obvious thing to say about chaotic systems is that they are intrinsically unpredictable in their detailed behavior. Their exquisite sensitivity means that we can never know enough to be able to predict with any long-term reliability how they will behave. Unpredictability is an epistemological statement, as the philosophers say, about what we can know. But in my metaphysical speculation, I shall want to go beyond that to make an ontological assertion about what is actually the case for the physical world. I want to say, in fact, that it is open in its process, that the future is not just a tautologous spelling out of what was already implicit in the past, but there is genuine novelty, genuine becoming, in the process in the history of the universe. Now, how can I justify taking such a possible but unforced step from epistemology to ontology, from what we can know to what is the case, from unpredictability to openness? I make that step on two grounds. The first ground is really a philosophical one. Like most scientists, philosophically, I am a critical realist. That's to say, I believe that our investigations lead us to a very similitudinous grasp of what the world is like. Now, I say very similitudinous, rather a mouthful, I say that rather than simply true, because, of course, our understanding of the world is never absolute, but it may well require correction when we explore new regimes of physical phenomena. We possess maps of the physical world, sufficiently accurate for many, but not for every purpose. Critical realism is, of course, a contended position in the philosophy of science. It's held by virtually all scientists, but not too many philosophers. But I believe it to be the only adequate account of what scientists are actually doing. I shall not argue the case here. I've tried to do so elsewhere, in a book called The Rochester Roundabout, which looks at the history of high-energy physics and asks what was happening in that history. So today, I shall simply be content to nail my colors to the mask as a self-confessed critical realist. Now, if you're a critical realist, you believe that what we know and what is the case are closely connected. That assertion is really a sort of working definition of what realism means. We critical realists have this wretched thing. I don't think I need it, really. We critical realists have epistemology, models, ontology written on our T-shirts. What we can know is closely connected with what is the case. That's what we believe. And you can see how natural that is for a scientist by recalling the early history of quantum theory. When Heisenberg wrote his celebrated paper on the uncertainty principle, he was concerned with analyzing what could be measured. His work was epistemological. It was what you could know, what you could measure. But it was not very long, however, before almost all physicists, not quite all, but almost all physicists gave it an ontological interpretation. The mainstream understanding of quantum theory sees the uncertainty principle as expressing a genuine ontological indeterminacy rather than a merely epistemological ignorance. And in an exactly similar way, it seems natural to me to interpret the undoubted unpredictability exhibited by chaotic systems as pointing in some way, which I'll talk about in a minute, to a genuine openness in the process of the physical world. And I have to say, I have to go on to say more later about exactly how I would interpret that. The second ground for embracing openness lies in its providing the possibility of reconciling physics with our basic experience as human beings, our basic experiences of responsibility and agency in facing an open future which we play our part in bringing about. Now, I know, of course, that the assertion of human free will has often been questioned or denied by philosophers. Indeed, what has not in the history of philosophy? But once again, I nail my colors to the mast. Ultimately, I believe, the denial of human freedom is incoherent for on its own terms, the assertion would then be the merely meaningless mouthing of an automaton. If I'm just determined and you're just determined, there is nothing rational about what I'm saying. It just happens. There is nothing rational, I'm afraid, about your listening. It just happens too. But I think we are not mistaken that there is a rational discourse going on between us here today. I am seized of the necessity, so often expressed by Professor Prigogine, of sciences being able to describe a world of which we can conceive ourselves as inhabitants. And it seems to me that an ontological interpretation of chaotic dynamics would be very helpful to that end. And let me emphasize that if that is so, the game is a game for physics, for physics. I'm not suggesting for a moment that until chaotic dynamics came along, we were uncertain whether we possessed powers of choice and agency. We have always known that we do. A knowledge quite as foundational as any knowledge on which science is based. Indeed, the whole scientific enterprise as pursued by scientists would not make sense without it. For as I've already said, if we were mere machines, we could not be rational beings. The advance, I think, lies in beginning to see a certain glimmering of how that experience can be integrated in a promising way with what physics has to say. So these considerations encourage me to take the possible, but undoubtedly speculative step, of giving a primacy to behavior over equations. Of interpreting deterministic chaos as pointing to an actual physical world of subtle and supple character, whose process is open to the future. And on this view, the deterministic equations from which our mathematical exploration began would be regarded as approximations in an emergent downward direction to this more subtle and supple reality. Now that phrase, in an emergent downward direction, requires some explanation. Let me first nail another set of colors to that rather cluttered mast. You see, a talk such as this cannot be given without presuppositions, which it must be my responsibility, at the very least, to acknowledge explicitly, of which I can't argue in detail if the talk is to have a tolerable length. I am an anti-reductionist. That is to say, I believe that biology is more than physics writ large. It has its own concepts and categories which are not reducible to those of physics alone. Those of us who hold this view, nor normally, and to my mind persuasively, defend it in terms of a theory of upward emergence, asserting that new properties emerge as one ascends the ladder of complexity of organization. I suspect, it's very frequently argued, I suspect, however, that that is only part of the story. If one believes that quarks and gluons are not more fundamental than cells or human beings, in other words, if one espouses a kind of ontological egalitarianism, which does not assign a uniquely fundamental role to elementary particle physics, an egalitarianism which are holistic inclinations, a desire to see things in their totality, would certainly encourage, if one does those things, then there may well be emergence in both directions, upwards and downwards, as one traverses the ladder of complexity. That's an idea I've tried to develop in more detail in a forthcoming book called Reason and Reality. On this view, classical determinist equations could be conceived of as emergent approximations to a more supple physical reality, as one made the simplifying assumption of treating the system in question as if it were isolatable from the rest of what is going on. We know, of course, that the exquisite sensitivity of chaotic systems, their vulnerability to the slightest external trigger, means that they are never truly isolatable. You might suggest that this particular metaphysical knot might more readily be cut by invoking quantum theory. After all, these exquisitely sensitive systems soon depend, for the form of their future behavior, on details more fine than Heisenberg will permit. Would it not be better to justify the openness of the future by employing this sensitive enmeshment of the everyday world with the indeterminate quantum world? Well, I can see some attraction in the suggestion, but I hesitate for several reasons. One, I have to say, is simply the gut feeling that everyday openness should not have to depend upon goings-on in the micro-world. Somehow that seems right to me, but even if it were mistaken there are other grounds for caution. One, of course, centers on the unresolved interpretive problems of quantum theory. It's an extraordinary paradox that quantum theory, which we've been using with immense, untainted success for 65 years, we still don't actually understand how to interpret it. Particularly, the so-called measurement problem is unresolved and its perplexities arise precisely from our unsureness of how to treat the interaction between the macroscopic and the microscopic. So we have to be careful on that ground. Another reason lies in the difficulties that have been found in exhibiting chaotic behavior in relation to the Schrodinger equation. I must say, I cannot but think that there must be at least some quantum analog of classical chaos, even if it takes a somewhat different form, a sort of fuzzy fractal form perhaps. But it would be necessary to see this settled before one ventured very far along the route of involving a quantum basis for openness. Now so far I have argued that chaos theory presents us with the possibility of a metaphysically attractive option of openness, a causal grid which delineates an envelope of possibility. For these chaotic systems, it's not the case that anything can happen, but many things can. It is, as we've often thought, a sort of structured randomness, a sort of patterned openness within which there remains room for maneuver. Now if that picture is right, how that maneuver is actually executed would, it seems to me, depend upon other organizing principles active in the situation when viewed holistically. It's a long speculative step from complex dynamical systems to even the biochemical dance of a single cell. And it is a yet longer step to dare to speak about mind and brain. But having embarked on my metaphysical voyage, I wish to push the exploration as far as I can. And I do so mindful of the warning uttered by Thomas Nagel that those who today venture to speak about such matters are indulging in pre-Socratic flailings around. It's a wonderful phrase from a wonderful book, The View from Nowhere. What Nagel means is that when the pre-Socratics, people like Anaximander, thought about the world, Anaximander thought, gosh, the world is just all made of air. If you make, if you rarify air, it becomes fire. If you condense it, it becomes water and then earth. Now in a sense, it was fantastically overambitious in 600 B.C. to figure out what the world was made of. It was an act of hubris to try to do so. On the other hand, it was also fantastically clever to have the notion that the varieties of the world, stuff, may in fact be composed of just a few fundamental types of stuff. Anaximander was the first elementary particle physicist and like many elementary particle physicists, he didn't get it right at first go. The same will be true of mind and brain. We are at the pre-Socratic stage. But nevertheless, we have to do the best we can. I think there is at least a hopeful direction in which to wave our arms. Now the classical accounts of mind and brain seem to me to be at all plausible. I cannot accept materialism's account that all is matter and mind is a sort of mere epiphenomenal ripple upon the surface, what the brain does, as the phrase goes. I can't accept that because there seems to me to be an unbridgeable gap between talking of the firing of neurons, however complex the pattern considered, and even the simplest mental experience of perceiving a patch of pink, let alone thinking hard. I cannot either accept idealism's account that the mental is the real and the physical world is a construct thereof because the stubborn facticity of the physical world, so familiar to the scientists as he or she seeks to explore it and is continually surprised by it, that facticity speaks to me of an independent reality standing over against our minds. Both materialism and idealism are implausible in their oversimplifications. Yet Cartesian dualism, with its talk of the thinking stuff of mind, leaves the two in unsatisfactory isolation from each other with no real clue to how they might interact. That they do so interact is made clear by our experiences of willed action and the effects of being hit on the head with a hammer. If it is not matter or mind or mind and matter, what then is left to us? I've suggested previously that we might try to consider a complementary metaphysic of mind stroke matter, what the philosophers would call a dual aspect monism. Monism means there is one stuff, but the dual aspect means that it is encountered in contrasting regimes, and in those contrasting regimes it gives rise to what we call the material and the mental. And the aim of any dual aspect monism is to treat these two polar extremes in as even-handed a way as possible. Each pole would have its own anchorage in the appropriate dimension of reality, for we participate both in the physical world and also in a noetic world, a world of thought. Now the adjective complementary, I said a complementary metaphysic of mind stroke matter, the adjective complementary is invoking a celebrated aspect of quantum theory, which as we all know, Niels Bohr drew particular attention to. If such invocation is to go beyond a mere slogan, it must indicate how the complementary poles are related to each other. Complementarity is not just an easy way of reconciling any pair of opposites you might care to take on board. So we have to indicate how the complementary poles are related to each other, and in suggesting how this might be, I wish to use quantum theory as a sort of analogical guide. One of its celebrated dualities is of course that of wave and particle, and quantum field theory tells us how that trick is done. A wave-like state is a state with an indefinite number of particles in it. That's a possibility quite foreign to classical physics, where you'd have to know how many particles there were, but it's permitted in quantum physics because of the latter's ability to mix together, superpose as we say in the trade, states which classically would be immiscible, not to be mixed together. Now the key to complementarity always seems to lie in some dimension of indefiniteness, and this suggests that mind-stroke matter might be reconciled by there being different poles of the world's stuff in greater or lesser states of flexible organization. Matter is the emergent downward side, mind the emergent upward side, where the arrow points in the direction of an intrinsic openness. Aha. Now, chaotic dynamics would represent the first primitive stirrings of openness as one mounted the ladder of complexity leading from matter to mind. A chaotic system faces a future of truth according to the indiscernible effects of infinitesimal triggers, nudging it this way or that. In the metaphysical extrapolation I'm making, which sees chaos theory as actually an approximation to a more subtle reality, these triggers of vanishingly small energy input will be transformed to become non-energetic items of information input, this way, that way, as bifurcating possibilities are negotiated. The way the envelope of possibilities actually traversed on this view depends upon downward causation by such information input, for whose operation it affords the necessary room for maneuver.