Science proceeds by articles; theology proceeds by books. Einstein's entire output in the celebrated annus mirabilis of 1905 was five articles that total seventy-five pages in length, while Louis de Broglie provided one of the foundational insights of quantum mechanics in a four-page paper in 1923. The defining works of theology, on the other hand, are more easily measured in pounds than pages—Aquinas' Summa Theologica, Calvin's Institutes, Barth's Church Dogmatics.

Notwithstanding this difference—and it is just the first of many ways in which the two fields tend to attract and shape persons of rather different temperaments—science and theology both require years of training and immersion in their respective, highly specialized languages. Physics may only require a few pages to lay out a fundamental theory, while theology requires a few volumes, but mastering either one requires a decade or more of study.

Yet the questions that science and theology ask are of interest to far more individuals than can expect to grasp the answers in their full technical glory. Fortunately, between the forbidding technicality of Einstein's papers and the off-putting heft of the average work of systematic theology, there is a kind of sweet spot: the invited lecture series. Such lectures constitute a genre all their own, defined by their unwritten but universal 60-minute time limit, the boundless curiosity and limited specialization of a general university audience, and—at least if the lecturer is John Polkinghorne—the capacity of an elder statesman to sort out with uncommon clarity the core issues of his field. And the result of these lectures—again, at least if the scholar in question is Polkinghorne—is a book that scientists, theologians, and lay people in every sense of the word can engage and enjoy.

Science and the Trinity: The Christian Encounter with Reality expands on the scientist-theologian's 2003 Warfield Lectures at Princeton Theological Seminary. The title and subtitle convey the distinctives of Polkinghorne's approach. On the one hand, as the title suggests, this is not really a treatise on "science and religion," with religion left so ill-defined that the book will frustrate practitioners of any actual faith. Polkinghorne is convinced that Trinitarian theology, anchored in "the scandalous particularity of the incarnation," is a better vantage point for engaging science than religion in the abstract. On the other hand, as the subtitle suggests, twenty years of work as a theoretical physicist have led Polkinghorne to the conviction that science delivers truth about reality, and he is determined not to evade the implications that reality may have for the theory and practice of Christian faith. His account of science and Christian theology succeeds unusually well in doing justice to both sides of the conversation.

Indeed, one of Polkinghorne's themes in Science and the Trinity is that science and theology have more in common than is often supposed. Philosophers of science have demonstrated the fundamental circularity of the scientific process: observations do not make sense without a theory, yet theories can only be constructed based on observations. The astonishing success of the scientific enterprise—the simple fact that mathematics, physics, and engineering form a continuum rather than being, to borrow a phrase from Stephen Jay Gould, non-overlapping magisteria—suggests that there is nothing inherently vicious about hermeneutical circles. Christian theology, no less than physics or chemistry, can be read as an attempt to make sense of real-world data—albeit a different sort of data—in a circular process of experience, theorizing, and "inference to the best explanation." So theology can be subjected to many of the same tests of plausibility as those which give science its force.

The hermeneutical character of science—its dependence upon theory to make sense of empirical observation—is much clearer to us in 2005 than it was in 1905. Fundamental scientific theories have proven to be anything but the simple deliverances of experience that Enlightenment empiricists expected. No one expects general relativity to be obvious to an undergraduate physics major, no matter how compelling its elegance and simplicity may be to those who understand it. Rather, scientists have come to expect fundamental theories to be, in Polkinghorne's apt phrase, "tough, surprising, and exciting."

By the same token, Polkinghorne argues, we cannot dismiss Trinitarian theology on the grounds that it is not obvious, or even because it is never explicitly outlined in the founding texts of the Christian tradition. To the contrary, the claim that God is best understood as Father, Son, and Spirit represents generations' worth of careful reflection on the data that confronted the early followers of Jesus of Nazareth and was preserved in the canon. "Of course this way of thinking is counterintuitive, just as so much of quantum theory is counterintuitive, but, just as in the case of quantum mechanics, that novel pattern of thought is forced upon us by the reality encountered and it does not arise from fanciful or unconstrained speculation."

Yet as with any good scientific theory, the Trinitarian account of creation, redemption, and ongoing divine sustaining has explanatory power that goes far beyond the initial data. "A deeply intellectually satisfying candidate for the title of a true 'Theory of Everything' is in fact provided by Trinitarian theology," Polkinghorne writes:

Our scientific ability to explore the rational beauty of the universe is seen to be part of the Father's gift of the imago Dei to humankind, and the beautiful rational order of the universe is the imprint of the divine Logos. … [Scientists'] repeated experiences of wonder at the disclosed order of the universe are, in fact, tacit acts of worship of its Creator.

Trinitarian thought, too, makes deeply intelligible the extraordinary fruitfulness of the universe, its information-generating character, and the relational underpinnings that quantum mechanics suggests lie underneath our experience of individuality. All these features of our universe, for which science per se can offer no explanation, are deeply consonant with the Trinitarian "theory." Tough, surprising, and exciting indeed.

So why do many scientists regard theology as the very antithesis of science? More than once in Catherine's professional career she has heard fellow scientists dismissively say, "That's religion, not science," not meaning that the idea being dismissed is concerned with the nature of God and God's relationship to the created universe, but rather meaning that it is fundamentally untestable. One reason for this ongoing misperception is that natural science is largely concerned with the reproducible behavior of the physical universe, whereas Christian theology is grounded in historical and particular events that are not subject to repetition and verification. This is a genuine and salient difference, even though scientists often forget that some of their own disciplines—such as astronomy and cosmology—rely extensively on historical data.

Yet Christians themselves have also contributed to this misunderstanding. Not long ago we were deep in conversation with friends (another physicist–writer married couple, as it happens) who asked Catherine with genuine curiosity how she reconciled being a Christian with being a scientist. When Catherine mentioned that she found the "theory" of the resurrection of Jesus to be by far the best explanation of the available historical evidence, one of them exclaimed, "I've never heard anyone talk about religious belief as based on evidence!" If many scientists have rarely encountered people of faith who expect their beliefs to be anchored in observable reality, that is not necessarily the scientists' fault.

With his vigorous advocacy for the rational character of Christian claims ranging from the Resurrection to the Trinity, Polkinghorne does much to reclaim ground that has been needlessly ceded in the science–religion dialogue even by thinkers who identify with the Christian tradition, from Ian Barbour to Arthur Peacocke, let alone claimed by secular scientists like Carl Sagan and Steven Weinberg, who relegate religion to the realm of the subjective and irrational. Reading Polkinghorne, one begins to hope that the 20th century's positivistic conceptions of "war" between science and theology may soon be a distant memory, and that even the patronizing rhetoric of "non-overlapping magisteria" may give way to a more mutually humble encounter between disciplines that recognize one another as both being enterprises fundamentally concerned with arriving at truthful accounts of reality.

The humility required does, however, go both ways. The implications of Polkinghorne's subtitle—his insistence that science delivers an increasingly accurate and fruitful account of reality—brings at least as much of a challenge to certain Christian assumptions as Catherine's explanation of the resurrection did to our friends' assumptions about the basis for religious belief.

For science seems to Polkinghorne to demonstrate resoundingly that the universe is "evolutionary" in character. This observation is by no means limited to biology: from the unimaginable early seconds after the Big Bang, to the structure of quantum effects with their built-in uncertainty and probabilistic nature, observable reality in both its history and its present form is not static, but dynamic.

To be sure, Polkinghorne, along with many others, is quick to point out the extraordinary fruitfulness of the universe's processes, to concur with Freeman Dyson that "the universe in some sense must have known we were coming," and to argue persuasively that once again Trinitarian belief makes such fruitfulness intelligible. But Polkinghorne takes very seriously modern physics' claim that the world is intrinsically indeterminate:

The God of love has not brought into being a world that is simply a divine puppet theatre, but rather the Creator has given creatures some due degree of creaturely independence. Trinitarian theology does not need to see the history of the world as the performance of a fixed score, written by God from all eternity, but may properly understand it as the unfolding of a grand improvisation in which the Creator and creatures both participate.

What does this imply about the classical theological—though not strictly biblical—language about God's omniscience and omnipotence? God is not the biblical God if he does not know everything there is to be known. But to go the further step of insisting that the future is already there to be known in the same way as the present or the past is to make a claim not about God, but about time.

In a Newtonian universe of law-governed billiard balls, of course, the entire history and future of the universe is implicit in any given moment, since the initial conditions and the laws of nature determine all future outcomes. In such a universe, God would indeed "know everything" in something like the classical sense of omniscience. However, such a universe also precludes freedom, and any divine intervention would require the kind of arbitrary rearranging of billiard balls that will get you into trouble at the Humean pool hall.

But whatever its merits or limits, physics has known for nearly one hundred years that this simply is not our universe. Our world is shaped by probabilistic events that, most physicists believe, are not knowable before they occur. And while it is beyond the scope of physics to pronounce definitively on this, the quantum mechanical universe makes space for the possibility that the universal human intuition that we are genuinely free (within evident limits) is true. Likewise, the biblical claim that God is genuinely present and active in the world no longer requires us to describe that active presence in terms that defy physical law.

Polkinghorne's approach to the broader question of divine omnipotence with respect to creaturely freedom is ingeniously faithful to the twin witnesses of Christian orthodoxy and contemporary science: Whatever limitations of either knowledge or power God has in relation to the created world are God's own doing. The Creator is omnipotent—there are no limitations on the kind of universe he could have created, a point strikingly reinforced by the many features of our universe that could just as well have been otherwise. But the world that the Creator has in fact created is a world with space for freedom—indeed, a world that seems astonishingly carefully prepared for the natural development of creatures that can exercise their freedom. In this world, God's knowledge and power are limited, but not because God is inherently limited. Rather, God has chosen to limit himself.

As Polkinghorne and a number of other theologians observed in the 2001 volume The Work of Love, this is a familiar idea with respect to the Incarnation—which for Christians refutes once and for all the Gnostic belief that God will have nothing to do with bodies. The Incarnation represented divine self-limitation and accommodation to an embodied creation, not a necessary limitation on God himself—kenosis, to echo the Greek word that Paul used in Philippians 2. Could it not also be, Polkinghorne and his colleagues have asked, that Creation involves kenosis? If so, we may need to abandon the Greek belief that God will have nothing to do with time.

It is worth noting how Polkinghorne's approach diverges both from thoroughgoing naturalism and from the intelligent design (ID) movement. On the one hand, Polkinghorne appreciates the extraordinary "anthropic" fruitfulness of not just Earth but the entire universe, something to which hard-core naturalists can seem almost willfully blind. Yet he is not inclined to dispute the overwhelming

consensus of biologists that life has arisen through an interplay between "chance and necessity" generally termed "evolution" (though Polkinghorne insists that chance is not as "blind" as the biochemist Jacques Monod claimed).

For Polkinghorne, the developmental nature of both life and the cosmos are simply a natural consequence of the Creator's gracious gift of freedom to the created order. Howard van Till, another physicist-turned-theologian, describes the universe as displaying "robust functional economy," meaning that the universe was created containing the fertile complexity needed to develop the astonishing array of life we observe, without requiring further supernatural input.

None of this necessarily rules out the fundamental contention of intelligent design—that certain aspects of life are too complex to have arisen without the guidance of a designer. Yet it does reveal how limited id's scope really is. On the one hand, ID attracts hostility from the scientific establishment because it seems to undercut science's hopes of understanding the workings of chance and necessity in the world. On the other hand, the only Designer of which ID can speak is little more than a shadowy cosmic Engineer, ready to intervene with clever solutions to problems, but whose ultimate intentions are unknown and, within the scope of ID theory at least, unknowable. Polkinghorne's Trinitarian account of a freely developing universe, on the other hand, can fully accept science's understanding of reality while also making much more specific claims about the nature of the world's Creator. That Creator turns out to be a loving Economist, a kind of endlessly resourceful Alan Greenspan, who creates and sustains an wondrously fruitful, free world.

Creates, sustains, and redeems—for perhaps the most notable and moving aspect of Polkinghorne's recent work is his attention to the stringent implications of current cosmology. Our universe, no less than our own bodies, is truly "in bondage to decay," inexorably descending into cold and lifeless disorder, albeit on a timescale of billions of years. Its ultimate futility poses a radical challenge not just to secular optimism but to any theology, such as process theology and its close relatives like panentheism, that has no place for the Creator's transcendence of creation. If "the world is God's body," in the phrase that is popular among certain ecologically concerned theologians, God is terminally ill.

It is here that resurrection becomes such a vital theological category. "The antidote to apocalyptic pessimism," Polkinghorne writes, "is the fundamental Christian picture of death and resurrection; a real death followed by real and unending new life, in which what had died is restored and transformed in order that it may finally enter into its 'true glory'." Not only bodies and souls but the cosmos itself will be rescued from bondage.

This hope depends upon a God who transcends the world yet has made himself known within it, just as orthodox Trinitarianism has always claimed. But here too Polkinghorne has something fresh to offer. The fatal defect in panentheism, he suggests, lies not so much in the idea that a time-bound, dynamic world could share in the life of a timeless God, but rather in an overrealized eschatology which assigns that participation to the "old creation" rather than to the "new creation" disclosed in the resurrected Son. "The new creation will be a world wholly suffused with the divine presence. … I do not accept panentheism as a present theological reality, but I do affirm the eschatological hope of a sacramental panentheism as the character of the new creation."

Could it be that both time and bodies are part of God's good creation and will ultimately share in God's own life? If so, perhaps there will be time in the new creation to plumb the depths not only of theology's massive books but science's compact equations, making scientist-theologians—or even economists—of us all.

Catherine Crouch teaches physics at Swarthmore College.
Andy Crouch is a writer and editorial director of the Christian Vision Project at Christianity Today.

Copyright © 2005 by the author or Christianity Today/Books & Culture magazine.
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