Stephen M. Barr is a theoretical particle physicist at the Bartol Research Institute of the University of Delaware. He is the author of Modern Physics and Ancient Faith forthcoming from the University of Notre Dame Press. This essay was originally presented in New York City on November 15, 2002 as the sixteenth annual Erasmus Lecture of the Institute on Religion and Public Life.
We often hear of a conflict between religion and science. Is there one? Certainly, some religious beliefs are scientifically untenable: for example, that the world is six thousand years old. However, for Jews and Christians not committed to a narrowly literalistic interpretation of Scripture, that kind of direct and clear–cut contradiction between scientific facts and religious doctrines does not exist.
What many take to be a conflict between religion and science is really something else. It is a conflict between religion and materialism. Materialism regards itself as scientific, and indeed is often called “scientific materialism,” even by its opponents, but it has no legitimate claim to be part of science. It is, rather, a school of philosophy, one defined by the belief that nothing exists except matter, or, as Democritus put it, “atoms and the void.”
However, there is more to materialism than this cold ontological negation. For many, scientific materialism is not a bloodless philosophy but a passionately held ideology. Indeed, it is the ideology of a great part of the scientific world. Its adherents see science as having a mission that goes beyond the mere investigation of nature or the discovery of physical laws. That mission is to free mankind from superstition in all its forms, and especially in the form of religious belief.
There are two grounds for the materialist’s indictment of religion as superstition. First, religion is supernaturalist. It teaches that there is a spiritual realm, and supposedly embraces mythological explanations and magical practices. Second, religion is (in the materialist’s eyes) irrationalist, because it is based on dogma, faith, and mystery. Science, being based on the natural and the rational, is therefore held to be fundamentally opposed to religion.
In other words, the scientific materialist maintains that there is a conflict between science and religion, and that it is intrinsic and a priori, in the sense that it would exist even if science had not yet made any definite discoveries about the world. This supposed opposition flows from what science and religion are in themselves, from their basic views of reality. However, the materialist claims more than this. He also says that many of the particular discoveries of science have demolished the credibility of religion. He claims, in other words, that there is also an a posteriori conflict between science and religion. This claim is based on a tendentious reading of scientific history, what I shall call the materialist’s “Story of Science.” According to this story, the great discoveries since the time of Copernicus and Galileo have disclosed a world that looks ever less like the picture religion painted of it, and have forced religious believers to fight a centuries–long rearguard action against the truth. Science has been the great debunker.
The claims of scientific materialism are hardly new. Indeed, they have not changed substantially in over a hundred years. And yet much else has changed in that time. We know much more than we did about the origins of science; we know vastly more about nature. It is a good time, therefore, to take a fresh look at the materialist ideology of science and its story of science to see how well they have held up in the light of new knowledge.
We begin with the issue of supernaturalism in religion and its supposedly superstitious character. I think we would all agree that most forms of belief in the supernatural are superstitious. However, we must remind ourselves of a vital historical fact, which is that many of these forms of supernaturalism were attacked, and at least partially overthrown, by biblical religion long before the advent of modern science. The Book of Genesis was itself in large part intended, scholars tell us, as a polemic against pagan superstition. For example, whereas the sun and moon were the objects of worship in pagan religion, the Book of Genesis taught that they were nothing but lamps set in the heavens to give light to day and night: not gods, but mere things, creatures of the one true God. Nor were animals and the forces of nature to be bowed down to by man as in pagan religion; rather man, as a rational being made in the image of God, was to exercise dominion over them.
It is true that the Bible is overwhelmingly supernatural in its outlook and literary atmosphere. However, what is critically important is that the Bible’s supernaturalism is concentrated in a God who is outside of Nature, and radically distinguished from the world He has made. Therefore the world of nature is no longer seen as populated by capricious supernatural beings, by fates and furies, dryads and naiads, gods of war or goddesses of sex and fertility. The natural world has been “disenchanted.” But whereas many give credit to science for this, the distinction belongs in the first instance to the monotheism of the Bible, which by depersonalizing and desacralizing the natural world helped clear the ground for the eventual emergence of modern science.
The Bible taught, then, that whatever reverence it is proper to have for the sun, or the forces of nature, or living things is due not to any divinity or spirituality that they possess, but to the fact that they are the masterworks of God. The universe thus came to be seen as a great work of engineering. We observe this in the Book of Proverbs, where the divine Wisdom is portrayed as a master craftsman directing the work of creation. And according to the rabbis of old the divine craftsman worked from a plan that was none other than the Torah itself. As they put it, “the Holy One, blessed be He, consulted the Torah when He created the world.” The Torah, then, was not merely a Law written in a perishable book, or part of a covenant with the people of Israel. It was an eternal Law in the mind of God which He imposed on the cosmos itself. The Lord says through the prophet Jeremiah: “When I have no covenant with day and night, and have given no laws to heaven and earth, then too will I reject the descendants of Jacob and of my servant David.” Psalm 148 tells of the sun, the moon, the stars, and the heavens obeying a divinely given “law, that will not pass away.” This emphasis on the lawfulness of the cosmos is found also in the earliest Christian writings. Minucius Felix in the second century wrote:
If upon entering some home you saw that everything there was well–tended, neat, and decorative, you would believe that some master was in charge of it, and that he was himself much superior to those good things. So too in the home of this world, when you see providence, order, and law in the heavens and on earth, believe that there is a Lord and Author of the universe, more beautiful than the stars themselves and the various parts of the whole world.
Note that these ancient texts do not point to supernatural phenomena or to the miraculous as evidence of God’s existence. Neither did St. Paul in the first chapter of Romans, where he discusses the grounds of belief in God. Nor did St. Thomas Aquinas in his famous five–fold proof. Belief in God is not founded upon supernatural manifestations but on the natural order, on the orderliness of things. The role of the miraculous in Judaism and Christianity is quite limited; it is to show God’s favor to His people and testify to the authenticity of the oracles of divine revelation, not to ground belief in the Creator.
There is something else that can be observed in these ancient texts, I think, that has some relevance to the long–debated question of Darwin and design. Many seem to have gotten the impression that the old Argument from Design for the existence of God is primarily an argument from biology. Richard Dawkins says, for instance, that it was the discovery by Darwin that biological structure could arise without design that “made it possible to be an intellectually fulfilled atheist.” However, most of the ancient Jewish and Christian texts seem to emphasize the structure of the cosmos as a whole more than the structure of living things. Jeremiah speaks of the covenant with day and night, and the laws given to heaven and earth; the Psalmist of the law obeyed by the sun, moon, stars, and heavens; and Minucius Felix of the providence, order, and law in the heavens and on earth.
It was in the heavens that the orderliness of nature was most evident to ancient man. It was this celestial order, perhaps, that first inspired in him feelings of religious awe. And it was the study of this order that gave birth to modern science in the seventeenth century. It is not altogether accidental, then, that it was an argument over the motions of the heavenly bodies that occasioned the fateful collision between science and religious authority that will forever be evoked by the name of Galileo. The case of Galileo raises another important historical point about supernaturalism and biblical religion.
Perhaps I can best introduce it with a personal story. I was asked a few years ago to give the response at a conference of scholars to a talk on the teaching of evolution in high schools. In my presentation I quoted the following piece of antireligious propaganda from a currently used high school biology textbook: “Every so often scientists stir up controversy when they explain part of the world that was considered beyond natural explanation—that is, belonging to the ‘supernatural.’” I disputed the idea that such controversies arise “every so often,” as the textbook asserted. I said that except for the battle over evolution I could think of no significant controversy that fit this description. At that point, as I had expected might happen, several members of the audience shouted out “Galileo!” But they had no reason to, for (as I went on to observe) the Galileo affair was most certainly not a debate about the supernatural. The geocentric theory that the Church in effect endorsed was no more supernatural than the heliocentric theory that it condemned. This was a clash between two perfectly naturalistic theories of astronomy. It was the veracity of Scripture that the Church authorities (mistakenly) saw themselves as upholding, not supernatural explanations of planetary motion over natural ones. (It is true that the inspiration of Scripture is supernatural, and that Galileo’s opponents thus thought they had supernatural warrant for believing what they did. But one may believe a natural fact on supernatural authority. I may believe that figs grow on trees or that Pontius Pilate was procurator in Judea because the Bible says so, without thinking that those facts are in any way supernatural in themselves.)
It was the same in physics: what Galileo and Newton overthrew were the erroneous, but perfectly naturalistic, theories of Aristotle. The Scientific Revolution of the seventeenth century had to overcome the naturalism of Aristotle, not the supernaturalism of Christianity. Christianity had already embraced naturalism in science five hundred years earlier, when Western Christians first encountered Greek science (or as it was called, natural philosophy) through translations from Greek and Arabic texts. Under the aegis of the Church, natural philosophy became a staple of medieval university education and was even a prerequisite for the study of theology. So comfortable were Christians with a naturalistic conception of the cosmos that it was a cliché already in the twelfth century for theologians and other writers to refer to the cosmos as a “machine.”
Now, while biblical religion has something to say about the existence of a natural order (which is simply a corollary of its teaching on God and creation), it has for the most part not regarded itself as having much to say about the detailed workings of that natural order. The materialist’s notion that religion is about providing mythological explanations of nature in the absence of real scientific understanding—the “God of the gaps” idea—is, as applied to biblical religion at any rate, itself a piece of mythology. It is instructive to look, for instance, at the Roman Catechism, or Catechism of the Council of Trent, published in 1566, exactly fifty years before Galileo’s first run–in with the Roman authorities. It contains not a word about botany, zoology, geology, or astronomy. Those were simply not considered part of Christian doctrine. That was the general attitude of the Catholic Church both before and after the Galileo affair, which can now be recognized as an adventitious and unique event in the history of the Church’s relationship with science. It was a bump—admittedly, a very bad bump—in what has otherwise been a smooth road.
It is notable, in this regard, that the Catholic Church never condemned, or even criticized or warned against, the theory of evolution. Its first statement on that subject did not come until 1950, when Pius XII isolated two points concerning evolution as being of doctrinal significance. Both concerned only human evolution. First, he said, the original unity of the human race has to be upheld. And second, whereas the human body might have evolved, the human spiritual soul, not being reducible to matter, cannot be held to have evolved. It was specially created by God in the first human beings as in all subsequent human beings. Here, in this one case, we do see the Church upholding a form of supernaturalism. It is the one great exception to the depersonalizing of nature by Judaism and Christianity. Man himself must not be depersonalized or reduced to the merely natural in the sense of the merely physical. I shall return to this all–important point.
I would like to interject here a comment about what I regard as backsliding from the fundamental Jewish and Christian perspective on nature by some recent theologies. On the one hand, we have some process theologians blurring the distinction between God and the universe, and treating the Godhead itself as part of the cosmic evolutionary process. On the other hand, we have some critics of Darwinism not merely arguing the inadequacy of that theory, but attacking the very idea of naturalism in biology, even when it comes to plants and animals, as inherently unbiblical or irreligious. Although these schools of thought are in some ways opposite, they are equally guilty, it seems to me, of smuggling supernaturalism back where it does not belong, and where neither science nor theology has ever needed it. Some anti–Darwinists need to be reminded that there is a natural order that comes from God, and the process theologians need to understand that God is the author of it, not a part of it.
We turn now to the second reason that the materialist indicts religion as superstitious, namely, its supposed irrationalism. The materialist sees faith and dogma as simply a matter of believing without reason. Religious mystery he imagines to be something dark and off–limits, something we are not meant to understand, and indeed beyond all understanding. All of this adds up, in his eyes, to an obscurantism that sets itself against intellectual freedom and the search for truth.
In responding to these misconceptions, I would like to begin with the notion of intellectual freedom. The great physicist Richard Feynman once observed that the freedom of the scientist is quite different from that of the artist or writer. The artist is free to imagine anything he pleases. The imagination of the scientist, however, is chained to experimental facts. The theories he dreams up must conform to what is already known from observation, and must be abandoned, no matter how rationally coherent, beautiful, or compelling they seem, if they are contradicted by new experimental facts. To put it in religious language, the scientist is answerable to a very stern and peremptory magisterium, the magisterium of Nature herself.
There is a clear analogy between the limitations on the scientist and those on the theologian. The scientist must submit his mind to the data of experiment, the theologian must submit his to the data of revelation. The word “data” means “the things that are given.” Both the religious person and the scientist accept givens. The givens may perplex. They may seem difficult to bring into harmony with each other or with what is known on other grounds. They may throw all our theories into confusion. But accepting the data must come before progress in understanding. That is why the words of St. Augustine apply, in a way, to the scientist as much as to the theologian: credo ut intelligam, “I believe in order that I may understand.”
So we see in science something akin to religious faith. The scientist has confidence in the intelligibility of the world. He has questions about nature. And he expects—no, more than expects, he is absolutely convinced—that these questions have intelligible answers. The fact that he must seek those answers proves that they are not in sight. The fact that he continues to seek them in spite of all difficulties testifies to his unconquerable conviction that those answers, although not presently in sight, do in fact exist. Truly, the scientist too walks by faith and not by sight.
The scientist is convinced that there are certain acts of insight, which he has not yet achieved, and which indeed no human being may ever achieve, that would satisfy a rational mind on the questions he has raised about nature. Faith in God is an extension of this attitude. The believer in God is convinced that reality is intelligible, not merely on this or that point, but through and through. There is some all–embracing act of insight that would satisfy all questioning and leave no further questions to be asked. Such an infinite and perfect act of insight is the state of being of God, indeed for the Christian and Jew it is God. In the words of the Jesuit philosopher Bernard Lonergan, God is the “unrestricted act of understanding” that grasps all of reality, all of being.
The materialist imagines that a religious mystery is something too dark to be seen. But, as G. K. Chesterton noted, it is really something too bright to be seen, like the sun. As Scripture tells us, God “dwells in unapproachable light.” The mystery is not impenetrable to intellect or unintelligible in itself; rather, it is not fully intelligible to us. And reason itself tells us that there must be such mysteries. For the nature of God is infinite, and therefore not proportionate to our finite minds. The mysteries of the faith primarily concern the nature of God, or they concern man in his relationship to God and as the image of God. They concern, that is, what is infinite or touches upon the infinite. Consequently, religious mystery hardly concerns, if it concerns at all, the matters studied by the physicist, chemist, or botanist. The things they study are quite finite in their natures and therefore quite proportionate to the human intellect. That is why there is nothing in Jewish or Christian belief that implies or suggests any limit to what human beings can understand about the structure of the physical world. Although the writings of scientific materialists are filled with hostility toward religious mystery, in fact religious mystery has never acted as a brake upon scientific progress.
This brings us back to the question of supernaturalism and its proper place. Supernaturalism is out of place in physics, astronomy, chemistry, or botany. However, it is necessary in anything that touches upon the nature of man, for man is made in the image of God. I have noted that biblical religion opposed the supernaturalism of the ancient pagan. In doing so, it clearly served the cause of reason. In our time, biblical religion serves the cause of reason just as much by opposing the absolute naturalism of the modern materialist. Where the ancient pagan went wrong is in seeing the supernatural everywhere in the world around him. Where the modern materialist goes wrong is in failing to see that which goes beyond physical nature in himself. By extending naturalism even to his own mind and soul, the materialist ends up sliding into his own morass of irrationalism and superstition. How so?
In the first place, a purely materialistic conception of man cannot account for the human power of reason itself. If we are just “a pack of neurons,” in the words of Sir Francis Crick, if our mental life is nothing but electrical impulses in our nervous system, then one cannot explain the realm of abstract concepts, including those of theoretical science. Nor can one explain the human mind’s openness to truth, which is the foundation of all science. As Chesterton observed, the materialist cannot explain “why anything should go right, even observation and deduction. Why good logic should not be as misleading as bad logic, if they are both movements in the brain of a bewildered ape.” Scientific materialism exalts human reason, but cannot account for human reason.
Nor can materialism account for many other aspects of the human mind, such as consciousness, free will, and the very existence of a unitary self. In a purely material world such things cannot exist. Matter cannot be free. Matter cannot have a self. The materialist is thus driven to deny empirical facts—not the facts in front of his eyes, but, as it were, the facts behind his eyes: facts about his own mental life. He calls them illusions, or redefines them to be what they are not. In lowering himself to the level of the animal or the machine, the materialist ultimately denies his own status as a rational being, by reducing all his mental operations to instinct and programming.
Thus, like the pagan of old, the materialist ends up subjecting man to the subhuman. The pagan supernaturalist did so by raising the merely material to the level of spirit or the divine. The materialist does so by lowering what is truly spiritual or in the divine image to the level of matter. The results are much the same. The pagan said that his actions were controlled by the orbits of the planets and stars, the materialist says they are controlled by the orbits of the electrons in his brain. The pagan bowed down to animals or the likenesses of animals in worship, the materialist avers that he himself is no more than an animal. The pagan spoke of fate, the materialist speaks of physical determinism.
Pope John Paul II has said that divine revelation reveals not only God to man but man to himself. It reveals to man that he is made in the image of God and therefore endowed with the spiritual powers of rational intellect and free will. Thus the supernaturalism of religion with regard to man is not an attack upon human reason, but ultimately the only basis upon which human reason can be adequately defended.
Up to this point I have been discussing the materialist’s claim that religion and science are intrinsically opposed because religion is incompatible with scientific naturalism and rationality. I now turn to the materialist’s other claim, that the actual discoveries of science since Copernicus have rendered the religious conception of the world incredible.
This is what I call the materialist’s Story of Science. It pervades the atmosphere of the scientific world and of popular writing on science. Let me now briefly outline that story. It has five major themes.
The first theme is the overturning of the religious cosmology—the Copernican theme. We now know that we do not live at the center of a cozy little cosmos, but in what Bertrand Russell called a “backwater” of a vast universe. The earth is a tiny planet, orbiting an insignificant star, near the edge of an ordinary galaxy that contains a hundred billion other stars, in a universe with more than a hundred billion other galaxies.
The second theme is the triumph of mechanism over teleology. The biblical religions did have the concept of a natural order, but they saw that order as embodying purpose. The arrangement of the world and the processes of nature they saw as being directed toward beneficent ends. That is why Christianity had little difficulty in accepting the naturalistic science of Aristotle, which was based on final causes. However, the Scientific Revolution occurred when it was realized that final causes could be dispensed with altogether in physics and that phenomena could be adequately explained in a completely mechanistic way in terms of preceding physical events. Even in biology, apparent purpose is now thought to arise from the undirected mechanism of natural selection acting on random genetic mutations. The materialist argues that the disappearance of purpose from nature undercuts the idea that nature is designed.
These first two themes blend together to give the third theme of the story, what the late Stephen Jay Gould called the “dethronement of man.” With the earth but an infinitesimal speck of flotsam in the limitless ocean of space, and the human race but a chemical accident, we can no longer believe ourselves to be the uniquely important beings for whom the universe was created.
The fourth theme, which goes back to Newton, is the discovery of physical determinism. The laws of nature were discovered to form a closed and complete system of cause and effect. Every event could be understood as arising inevitably from the past state of the universe in a way that is precisely determined by the mathematical laws of physics. As Laplace said in the eighteenth century, if the state of the world were completely known at one time, its whole future development could in principle be calculated down to the minutest detail. If this is true, it spells the death of the Jewish and Christian doctrine of free will. For even if we had wills that were free, they could have no effect upon the world of matter, including our bodily organs. They could not affect, in particular, what we say or do.
This leads to the fifth and final theme of the materialist’s story, the emergence of a completely mechanistic view of man himself. Already in the seventeenth century the possibility was widely discussed that animals could be understood as machines or automata. The more radical thinkers of the Enlightenment, like La Mettrie and Baron d’Holbach, extended this view to man. Now, with the processes of life understood in terms of chemistry, and the brain understood to be a complex biochemical computer, the triumph of this mechanistic view of man seems virtually complete.
The story that I have just outlined should not be lightly dismissed. There are many people, not all of them hostile to religion, who find this interpretation of scientific history not only plausible but compelling. And it must be admitted that, in part, this is because much in scientific history up through the nineteenth century lent itself to this interpretation, or seemed to. And the startling developments in physics in the twentieth century only reinforced this view of things. People saw dramatic discoveries, like Einstein’s theory of relativity and quantum theory, as demonstrating once again that all traditional or familiar or intuitively obvious notions are naive and fated to be cast aside. Science as debunker, it seemed, was continuing on its relentless course.
However, this view of twentieth–century science is misleading. It is true that science debunked many ideas in the twentieth century, but what it chiefly debunked, I will now argue, was the materialist’s old Story of Science. This was not fully appreciated, because people saw what they expected to see. They extrapolated from the past story line. But the discoveries of the twentieth century threw some twists into the plot. Those twists have, in my view, invalidated, or at least called into serious question, every lesson that the materialist wished us to draw from scientific history.
What are those twentieth–century plot twists? There are, it so happens, five of them, which correspond rather closely to the five themes of the materialist’s story of science.
We recall that the first theme of that story was the Copernican one, the overthrow of the religious cosmology, and in particular of the supposedly religious idea that man is at the center of the universe. I say supposedly religious idea, because in historical fact the notion that the universe has a center entered Western thought not from the Bible, which knows no such idea, but from Ptolemy and Aristotle. However, there was a question about the structure of the cosmos that historically really did divide Jews and Christians from materialists and pagans. That question was not about space and whether it has a center, it was about time and whether it had a beginning.
The idea that the universe and time itself had a beginning really did enter Western thought from the Bible, and indeed from the opening words of the Bible. Virtually all the pagan philosophers of antiquity, including Aristotle, and, according to most scholars, Plato, held that time had no beginning. Modern materialists and atheists, for obvious reasons, have generally followed the ancient pagan view.
For a very long time, all the indications from science seemed to tell against the idea of a beginning. In Newtonian physics it was natural to assume that both time and space were boundless and infinite in extent. The simplest assumption was that time coordinates, like space coordinates, extended from minus infinity to plus infinity. The discovery of the law of conservation of energy gave further support to the idea of the eternity of the world, for it said that energy could be neither created nor destroyed. And chemists discovered that the quantity of matter, as measured by its mass, is also unchanged in physical processes. Thus almost every scientific indication at the beginning of the twentieth century was that space, time, matter, and energy had always existed and always would. One more nail in the coffin of religion, it would seem. But then came the first plot twist.
The first intimation that time could have had a beginning came from Einstein’s General Theory of Relativity—that is, his theory of gravity. In the 1920s, the Russian mathematician Alexander Friedmann and the Belgian physicist Georges Lemaître (who was also a Catholic priest) independently proposed mathematical models of the universe, based on Einstein’s theory, in which the universe is expanding from some initial explosion, which Lemaître called the “primeval atom,” and which is now called the “Big Bang.” Observational evidence for this cosmic expansion was announced a few years later, in 1929, by the American astronomers Edwin Hubble and Milton Humason.
The initial reaction of some scientists to the idea of a beginning was extremely negative. The eminent German physicist Walter Nernst declared, “To deny the infinite duration of time would be to betray the very foundations of science.” As late as 1959, thirty years after the discovery of the expansion of the universe, a survey of leading American astronomers and physicists showed that most still believed that the universe had no beginning. Not all, but certainly some, of the resistance to the idea of a beginning can be attributed to materialist prejudice.
None of this is to say that the Big Bang proves the biblical doctrine of creation, or even that it proves conclusively that time had a beginning. It is possible that something existed before the Big Bang, even though in the simplest and currently standard model of cosmology nothing did. Nevertheless, it remains true that on the one question of cosmology where Jewish and Christian doctrine really did have something to say that conflicted with the expectations of materialists and atheists—the question of a beginning—the evidence as it now stands seems strongly to favor the religious conception.
The second theme of the materialist’s story was the triumph of mechanism over teleology. Instead of seeing purpose in nature, and thus a Person behind the purpose, science came to see only the operation of impersonal laws. There was no need for a cosmic designer, for it was the laws of physics that shaped and sculpted the world in which we live. When Laplace was asked by Napoleon why God was never mentioned in his great treatise on celestial mechanics, Laplace famously answered, “I had no need of that hypothesis.” This revealed a shift in perspective. Whereas once the laws of nature had been seen as pointing to a lawgiver, they were now seen by some as constituting in themselves, and by themselves, a sufficient explanation of reality. This brings us to the second plot twist in the story of science. In the twentieth century another shift in perspective took place. One might call it the aesthetic turn. This requires some explanation.
Physics begins with phenomena that can be observed with the senses, perhaps aided by simple instruments, like telescopes. It finds regularities in those phenomena and seeks mathematical rules that accurately describe them. Physicists call such rules empirical formulas or phenomenological laws. At a later stage, these rules are found to follow from some deeper and more general laws, which usually require more abstract and abstruse mathematics to express them. Underlying these, in turn, are found yet more fundamental laws. As this deepening has occurred, two things have happened. First, there has been an increasing unification of physics. Whereas, in the early days of science, nature seemed to be a potpourri of many kinds of phenomena with little apparent relation, such as heat, sound, magnetism, and gravity, it later became clear that there were deep connections. This trend toward unification greatly accelerated throughout the twentieth century, until we now have begun to discern that the laws of physics make up a single harmonious mathematical system.
Second, physicists began to look not only at the surface physical effects, but increasingly at the form of the deep laws that underlie them. They began to notice that those laws exhibit a great richness and profundity of mathematical structure, and that they are, indeed, remarkably beautiful and elegant from the mathematical point of view. As time went on, the search for new theories became guided not only by detailed fitting of experimental data, but by aesthetic criteria. A classic example of this was the discovery of the Dirac Equation in 1928. Paul Dirac was looking for an equation to describe electrons that was consistent with both relativity and quantum theory. He hit upon a piece of mathematics that struck him as “pretty.” “[It] was a pretty mathematical result,” he said. “I was quite excited over it. It seemed that it must be of some importance.” This led him to the discovery that has been justly described as among the highest achievements of twentieth–century science.
The same quest for mathematical beauty dominates the search for fundamental theories today. One of the leading theoretical particle physicists in the world today, Edward Witten, trying to explain to a skeptical science reporter why he believed in superstring theory in spite of the dearth of experimental evidence for it, said, “I don’t think I’ve succeeded in conveying to you its wonder, incredible consistency, remarkable elegance, and beauty.”
All of this has changed the context in which we think about design in nature. When the questions physicists asked were simply about particular sensible phenomena, like stars, rainbows, or crystals, it may have seemed out of place to talk about them, however beautiful they were, as being fashioned by the hand of God. They could be accounted for satisfactorily by the laws of physics. But now, when it is the laws of physics themselves that are the object of curiosity and aesthetic appreciation, and when it has been found that they form a single magnificent edifice of great subtlety, harmony, and beauty, the question of a cosmic designer seems no longer irrelevant, but inescapable.
In 1931, Hermann Weyl, one of the great mathematicians and physicists of the twentieth century, gave a lecture at Yale University in which he said the following:
Many people think that modern science is far removed from God. I find, on the contrary, that it is much more difficult today for the knowing person to approach God from history, from the spiritual side of the world, and from morals; for there we encounter the suffering and evil in the world, which it is difficult to bring into harmony with an all–merciful and almighty God. In this domain we have evidently not yet succeeded in raising the veil with which our human nature covers the essence of things. But in our knowledge of physical nature we have penetrated so far that we can obtain a vision of the flawless harmony which is in conformity with sublime reason.
The third theme of the materialist’s story was the “dethronement of man.” A classic statement of this view was given by Steven Weinberg in his book The First Three Minutes. He wrote:
It is almost irresistible for humans to believe that we have some special relation to the universe, that human life is not just a farcical outcome of a chain of accidents, . . . but that we were somehow built in from the beginning. . . . It is very hard for us to realize that [the entire earth] is just a tiny part of an overwhelmingly hostile universe. . . . The more the universe seems comprehensible, the more it also seems pointless.
Certainly, given the immensity of the universe and the impact of Darwinian ideas, it is easy to understand why this sentiment is widespread. However, in the last few decades there has been a development that suggests a very different estimate of man’s place in the universe. This plot twist was not a single discovery, but the noticing of many facts about the laws of nature that all seem to point in the same direction. These facts are sometimes called “anthropic coincidences.”
The term “anthropic coincidence” refers to some feature of the laws of physics that seems to be just what is needed for life to be able to evolve. In other words, it is a feature whose lack or minute alteration would have rendered the universe sterile. Some of these features have been known for a long time. For example, William Paley, already in 1802, in his treatise Natural Theology, pointed out that if the law of gravity had not been a so–called “inverse square law” then the earth and the other planets would not be able to remain in stable orbits around the sun. Perhaps the most famous anthropic coincidence was discovered in the 1930s, when it was found that except for a certain very precise relationship satisfied by the energy levels of the Carbon–12 nucleus, most of the chemical elements in nature would have occurred in only very minute quantities, greatly dimming the prospects of life.
Interest in and attention to anthropic coincidences has greatly intensified since the work of the astrophysicist Brandon Carter in the 1970s. Many such coincidences have now been identified. The most natural interpretation of them is that we were indeed “built in from the beginning,” in Steven Weinberg’s phrase, and that the universe, far from being “overwhelmingly hostile” to us, as he asserted, is actually amazingly, gratuitously hospitable.
Most scientists take a very jaundiced view of the whole subject of anthropic coincidences. They have some respectable reasons, but the major reason, in my experience, is a knee–jerk reaction against anything that smells like religion or teleology. Moreover, those well–known scientists who have shown interest in anthropic coincidences generally see them as having an explanation that does not invoke purpose in nature. They appeal to what is sometimes called the Weak Anthropic Principle. This is the idea that a variety of different laws of physics apply in different regions of the universe, or even in different universes, and that so many possible laws of physics are sampled in this way that there is really no coincidence in the fact that in some places the laws are “just right” for life. This is a very speculative idea, and as an explanation of all the anthropic coincidences it faces formidable difficulties. However, it cautions us that the anthropic coincidences may not point unambiguously to cosmic purpose. Yet these coincidences do completely vitiate the claim that science has shown life and man to be mere accidents. If anything, the prima facie evidence is in favor of the biblical idea that the universe was made with life and man in mind.
The fourth theme of the materialist’s story was the determinism of physical law. Everything in the history of physics up until the last century seemed to support this idea. All the laws discovered—those of mechanics, gravity, and electromagnetism—were deterministic in character. If anything seemed securely established it was physical determinism. However, in the 1920s the ground rumbled under the feet of physicists. Determinism was swept away in the quantum revolution. According to the principles of quantum theory, even complete information about the state of a physical system at one time does not determine its future behavior, except in a probabilistic sense.
This was terribly shocking to physicists. Indeed, one of the hallmarks of an exact science is its ability to predict outcomes. So shocking was this twist in the plot that several of the makers of the quantum revolution, including de Broglie and Schrödinger, were reluctant to accept this aspect of it. Einstein was never reconciled to the loss of determinism. “God,” he famously said, “does not play dice.” There have been many attempts to restore determinism to physics by modifying, reformulating, or reinterpreting quantum theory in some way. So far, however, it seems unlikely that the old classical determinism will be restored.
There are many who argue, nonetheless, that the indeterminacy of quantum theory does not create an opening or a space for free will to operate. They argue that the basic building blocks of the human brain, such as neurons, are too large for quantum indeterminacy to play a significant role. At this point, who can say? So little is known about the brain. What we can say is that there was for a long time a strong argument from the fundamental character of physical law against the possibility of free will, and this argument can no longer be so simply made. To quote Hermann Weyl again, from the same 1931 lecture:
We may say that there exists a world, causally closed and determined by precise laws, but . . . the new insight which modern [quantum] physics affords . . . opens several ways of reconciling personal freedom with natural law. It would be premature, however, to propose a definite and complete solution of the problem. . . . We must await the further development of science, perhaps for centuries, perhaps for thousands of years, before we can design a true and detailed picture of the interwoven texture of Matter, Life, and Soul. But the old classical determinism of Hobbes and Laplace need not oppress us longer.
We return, now, to the final theme of the materialist’s story, the mechanistic view of man himself. It is the final theme in more ways than one. Here the scientist debunks himself. Here all the grand intellectual adventure of science ends with the statement that there is no intellectual adventure. For the mind of man has looked into itself and seen nothing there except complex chemistry, nerve impulses, and synapses firing. That, at least, is what the materialist tells us that science has seen. However, the story is really not so simple. Here again the plot has twisted. Two of the greatest discoveries of the twentieth century cast considerable doubt upon, and some would say refute, the contention that the mind of man can be explained as a mere biochemical machine.
The first of these discoveries is quantum theory. In the traditional interpretation of quantum theory—sometimes also called the “Copenhagen,” “standard,” or “orthodox” interpretation—one must, to avoid paradoxes or absurdities, posit the existence of so–called “observers” who lie, at least in part, outside of the description of the world provided by physics. That is, the mathematical formalism which quantum theory uses to make predictions about the physical world cannot be stretched to cover completely the person who is observing that world. What is it about the “observer” that lies beyond physical description? Careful analysis suggests that it is some aspect of his rational mind.
This has led some eminent physicists to say that quantum theory is inconsistent with a materialistic view of the human mind. Eugene Wigner, a Nobel laureate in physics, stated flatly that materialism is not “logically consistent with present quantum mechanics.” Sir Rudolf Peierls, another leading twentieth–century physicist, said, on the basis of quantum theory, “The premise that you can describe in terms of physics the whole function of a human being . . . including its knowledge, and its consciousness, is untenable. There is still something missing.”
Admittedly, this is a highly controversial view. That is only to be expected, especially given the materialist prejudice that affects a large part of the scientific community. Moreover, the traditional interpretation of quantum theory has aspects that many find disturbing or implausible. Some even think (wrongly, in my opinion) that the role it assigns to observers leads to subjectivism or philosophical idealism. Dissatisfaction with the traditional interpretation has led to various rival interpretations and to attempts to modify quantum theory. However, these other ideas are equally controversial. The controversy over quantum theory will not be resolved any time soon, or perhaps ever. But, even if it is not, the fact will remain that there is an argument against materialism that comes from physics itself, an argument that has been advanced and defended by some leading physicists and never refuted.
The second discovery that arguably points to something nonmaterial in man is a revolutionary theorem in mathematical logic proved in 1931 by the Austrian Kurt Gödel, one of the greatest mathematicians of modern times. Gödel’s Theorem concerns the inherent limitations of what are called “formal systems.” Formal systems are essentially systems of symbolic manipulation. Since computers are basically just machines for doing such symbolic manipulations, Gödel’s Theorem has great relevance to what computers and computer programs can do. It was recognized fairly quickly that Gödel’s Theorem might have something to say about whether the human mind is just a computer—Gödel himself was firmly convinced that it is not. Indeed, he called materialism “a prejudice of our time.” However, he never developed, at least in print, the argument against materialism based on his own theorem. That was first done by the Oxford philosopher John R. Lucas. In 1961, Lucas wrote,
Gödel’s theorem seems to me to prove that Mechanism is false, that is, that minds cannot be explained as machines. So has it seemed to many other people: almost every mathematical logician I have put the matter to has confessed similar thoughts, but has felt reluctant to commit himself definitely until he could see the whole argument set out, with all objections fully stated and properly met. This I attempt to do.
Both Gödel’s Theorem and Lucas’ argument are extremely subtle, but we can state the gist of them as follows. Gödel’s Theorem implies that a computer program can be outwitted by someone who understands how it is put together. Lucas observed that if a man were himself a computer program, then by knowing how his own program was put together he could outwit himself, which is a contradiction. One may explain the Lucas argument in another way. Gödel’s Theorem also showed that it is beyond the power of any computer program that operates by logically consistent rules to tell that it is doing so. However, a human being, Lucas noted, can recognize his own consistency—at least at times—and so must be more than a mere computer.
In recent years, the eminent mathematician and mathematical physicist Sir Roger Penrose has taken up the Lucas argument, further refined it, and answered criticisms that had been leveled at it by mathematicians and philosophers. This has not quieted the criticism. However, the Gödelian argument of Lucas and Penrose, though often attacked, has never been refuted.
Where does this all leave us? After all the twists and turns of scientific history we look around and find ourselves in very familiar surroundings. We find ourselves in a universe that seems to have had a beginning. We find it governed by laws that have a grandeur and sublimity that bespeak design. We find many indications in those laws that we were built in from the beginning. We find that physical determinism is wrong. And we find that the deepest discoveries of modern physics and mathematics give hints, if not proof, that the mind of man has something about it that lies beyond the power of either physics or mathematics to describe.
Chesterton told the story of “an English yachtsman who slightly miscalculated his course and discovered England under the impression that it was an island in the South Seas.” The explorer, he said, “landed (armed to the teeth and speaking by signs) to plant the British flag on that barbaric temple which turned out to be the pavilion at Brighton.” Having braced himself to discover New South Wales, he realized, “with a gush of happy tears, that it was really old South Wales.”
Science has taken us on just such an adventure. Armed not with weapons but with telescopes and particle accelerators, and speaking by the signs and symbols of recondite mathematics, it has brought us to many strange shores and shown us alien and fantastic landscapes. But as we scan the horizon, near the end of the voyage, we have begun to recognize first one and then another of the old familiar landmarks and outlines of our ancestral home. The search for truth always leads us, in the end, back to God.