The following is reproduced from the November/December 1995 issue of Mercury (vol. 24, number 6, pages 12-15), and is copyright 1995 by the Astronomical Society of the Pacific. Their copyright and reproduction policy is as follows: "If you are an instructor in a nonprofit educational institution, we welcome you to photocopy any article from Mercury (issues starting with September/October 1994). Copies should be clearly marked with a copyright notice of the form, (c) 1995 Astronomical Society of the Pacific. No further permission from us is necessary."

A Non-Dialogue on the Two Great World Systems

William Keel, University of Alabama

A great many high-school and university courses in astronomy, biology, and geology inculcate a thumbnail history of Western science which runs somewhat as follows:

The ancient city-states in the Middle East started along the road to systematic observation and recording while they suffered under oppressive theocratic regimes. The Greek world took the first real steps toward empirical science, though their philosophical feet of clay left stumbling blocks for later peoples. The Roman conquerors were interested in technology, not science, and so preserved Greek knowledge in, at best, a static form. Medieval Europe reverted to oppressive theocracy, challenged only when science and empiricism were rediscovered from the Arab world and built upon during the Renaissance. Nicholaus Copernicus and finally Galileo Galilei showed that the prevailing religious world view was utterly at odds with reality. When the Church showed its true colors in stifling Galileo, the battle lines between the light of reason and the blindness of faith were drawn. An enlightened citizenry could then see the Church for what it was: the enemy of free inquiry and unacceptable thought. Subsequent history has shown a continual retreat of insidious superstition before the advance of human knowledge.

There is, of course, a mirror image to this view of events, to be heard from pulpits and parochial schools:

The spiritual structures maintained in the European medieval chaos were all that stood between people and despair. As conditions improved, clerics such as Copernicus led the way toward a new, more accurate view of the world. The regrettable mistakes made in the Galileo incident led to an unnecessary schism in Western thought, one which has been exploited ever since by individuals promoting their own philosophical viewpoints and justifying their deeds without heed to moral restraints. Unrestrained by spiritual principles, science and technology have given the modern world horrors undreamt of outside apocalyptic writings. Many in positions of authority view religion as something to be wiped out, or at the very least denied any place in public life.

Stated so starkly, it is not difficult to see the germs of truth and the fallacies in each of these chronicles. In perhaps more subtle form, they continue to guide far too much policy and thought. The conflict between scientific and religious, rationalist and spiritual, views of the world is implicated in many of today's political issues. Much of this ``conflict'' is driven by needless posturing; it is not inherent in the nature of either world view.

If any of the sciences is central to the science-faith debate, it is astrophysics. The Galileo affair and the Copernican uprooting of Earth from its hitherto privileged mental position were bad enough, but modern astronomy has revealed a universe of almost inconceivable vastness and age, one which seems quite indifferent to the existence and concerns of mortals. The spiritual concerns are very real for scientists working at the frontier of physical cosmology, where questions of how blur with questions of why.

The Feast of Reason, the Flow of Soul

"The idea that religion may be a way of organizing one's appraisal of one's place in the world is not very different from what astrologers tell their clients,'' John Maddox, the editor of the journal Nature, wrote last year. ``In other words, it may not be long before the practice of religion must be regarded as anti-science.'' From such rhetoric, and from the vituperic literature put out by young-Earth creationists, one would never guess that there are many mainstream, productive, and creative scientists who are deeply religious. In the current polarized climate, they are hardly motivated to be visible. Yet they can be found, in organizations such as the American Scientific Affiliation. On their behalf, I protest the simplistic, self-absorbed views that pass for debate on these issues.

What do we mean when we speak of science and religion? Science can be used in many ways: as the body of accumulated knowledge about the world, as the method of interplay between theory and experiment, as the whole social enterprise that applies one of these to add to the other. The purpose of all of these is very close to M. Scott Peck's working definition of what we do as we mature: gradually make our mental picture of the world, our internal ``map,'' reflect reality as shown by our senses, or other means of measurement.

Like the conventional image of science, the typical anthropologist's definition of religion -- such as that proposed by J.G. Frazer in The Golden Bough, ``a belief in powers higher than man and an attempt to propitiate or please them'' -- is too narrow. Religion includes the efforts to put oneself in harmony with that higher being or kind of existence, independent of any particular manipulative intent.

Thus, the scientific world view grants primacy to data over philosophical preconceptions. Although historians of science rightly point to the many instances in which social factors have weighed heavily in scientific decisions, few physical scientists deny the reality check in science. In contrast, religion accords primacy to moral imperatives, first and last things. It is as incomplete to claim that religion is an outmoded attempt to explain a frightening universe as it is to claim that science is a futile attempt to exercise control over that universe.

The two approaches have common ground: Science can help us to learn about ourselves and our world and its findings can inform matters of faith and practice, and religious views inescapably shape our curiosity and applications in science and technology. As Immanuel Kant wrote in Critique of Pure Reason, ``Two things fill my mind with ever-increasing wonder... the starry heavens above me and the moral law within me.''

That said, it would be disingenuous to say that there is no conflict between the approaches. Scientists who practice religious faith do feel an internal tension, but the private and institutional treatments of this tension differ. The richness of the interplay between reason and faith is lost among the absolutes of the public arena.

The Kingdoms of Heaven

Early in the history of Christianity, voices warned that political imperatives could polarize the rationalist and spiritual ways of thinking. In the fifth century, St. Augustine wrote, ``We should not hold rashly an opinion in a scientific matter, so that we may not come to hate later whatever truth may reveal to us, out of love for our own error."

Because the institution that we recognize as science took root in Europe and its cultural offspring, the encounters between science and religion have historically involved Christianity. The arbiters of Islamic culture seem to have had their failure of nerve in this regard well before the eclipse of Islam by European culture, as Imad Ahmad discussed earlier this year in Mercury [see ``The Science of Knowing God,'' March/April, p. 28].

As John Hedley Brooke described in his book Science and Religion, within Christianity many of the skirmishes in the feud came about as results of internal political maneuver in one of the camps, rather than an unavoidable conflict based on the basic tenets of either. When it suits them, leaders can reverse their positions and seek ideological support post facto. In 17th-century England the Anglican clergy reversed the traditional belief in spirit possession, apparently to discredit Puritan and Catholic positions. As Richard Olson described three years ago in Skeptic magazine, rationalist thinkers responded with their own do-si-do, changing their position on the reality of non- material beings.

The Crusades, nuclear weapons, apologies for slavery, social Darwinism... the litany could go on, including most of the armed conflicts and much of the social turmoil in today's world. The ideas of science and religion are mobilized in support of political power, and often they wind up on different sides of the front line. It hardly helps that these two institutions waste a fair amount of effort in conflict with one another.

Central to the history of the uneasy relationship is the Galileo affair. This episode has been discussed often -- see, for example, Giorgio de Santillana's The Crime of Galileo -- and so I will not rehash the details except to underscore its crucial role. As James Reston wrote in Galileo, ``Science and faith clashed, and in their terrible conflict, the two were severed, to continue in divergent directions and to lose their common ground. In its insistence on the total victory of theology, the Catholic church branded itself to the modern world as anti-science and obscurantist. It is still struggling to overcome the curse of 1616. And science, fearing the spiritual, became increasingly dry and bloodless, to the point that even the most fantastic discoveries in today's heavens have lost the power to move the soul and spirit of mortals.''


Galileo's ultimate confrontation with the Roman Catholic Church was provoked by the 1632 publication of his book Dialogue on the Two Great World Systems, a seminal document in philosophy and civilized thought no less than in astronomy itself. The book consists of thoughtful conversations between representatives of the Aristotelian view and of Galileo's own Copernican (and post-Copernican) views, in the persons of Simplicio and Salviati. Picking ``Simplicio'' as the name for a defender of the Ptolemaic system, and a great deal else about which Aristotle had been rather demonstrably wrong, could hardly have endeared Galileo to the powers that be. A third person, Sagredo, serves as referee and foil in the debates. They discuss the arrangement of Earth, Sun, and planets; projectile motion; the cause of the seasons; and the origin of tides. Not surprisingly, Simplicio often espouses ridiculous, though at the time hardly uncommon, arguments for the immobility of Earth and the distinction between terrestrial and celestial matter.

The appearance of the Dialogue led to Galileo's house arrest, trial at the hands of the Holy Office, and the listing of this book on the Index of Prohibited Works for two centuries. Yet, even within the Church, Galileo's views had the last laugh. In 1893, Pope Leo XIII's encyclical, Providentissimus Deus, endorsed the Galilean approach to Scriptural interpretation in matters not directly related to faith and doctrine.

I cannot resist borrowing the same literary form to comment on the aftermath of the Galileo matter three and a half centuries later. If any of the arguments here are original, it is entirely accidental; most have certainly been spoken or written by others. Although two great world systems are indeed involved, in would be a laughable overstatement to call their current level of public discourse a dialogue. I refer to the protagonists as VR (Voice of Reason) and VF (Voice of Faith). We begin with them speaking not so much to as past one another.

VR: We would have thought that the vestiges of superstition so regrettably prevalent even in educated circles under the name of ``religion'' would have finally disappeared before this century's advances in our understanding of the universe. It is now clear that life, consciousness, the existence of Earth and universe can be explained by purely physical processes as we understand them. There is no need to postulate anything beyond the physical -- no measurable, quantifiable phenomena whose explanation requires or even suggests the existence of anything supernatural, much less supernatural entities with specific attributes remotely resembling those of people. As Robert Heinlein wrote, ``supernatural is a null word.''

VF: It is a remarkable testimony to the enduring qualities of faith that religion thrives today under the most unlikely circumstances: in the Western world after a century of assault from academic and intellectual circles; in the former Soviet Union, after three generations of official attitudes ranging from discouragement to persecution; and even underground in China. People are finding that rationalism simply doesn't square with basic human needs. It doesn't provide answers to the questions that, for most of us, are the most important in life. To this day, many people find that their experiences of life and thought lead them beyond the visible world.

VR: We need to be vigilant when those advocating a religious agenda try to tamper with education. Surely belief in a supreme, perhaps even caring, being does not require that the entire edifice of science is a diabolical lie? The evidence for an old Earth, a long and unfolding history for life, and a very large and very old universe is so compelling that to deny it is simply to drive students to reject all vestiges of religious belief; the scientific world view has all the evidence on its side.

Stubbornness in what they are told to believe is driving students toward false choices. One can stand only to lose by conflating a philosophical agenda with manifest facts; telling the universe how it must behave has a very poor track record. Bait-and-switch tactics are worse than intellectually dishonest (if such a thing is possible). They will eventually prove repellent.

VF: We need to be vigilant when those advocating a materialist agenda try to dictate education. Surely the recognition that life on Earth has changed over time, and that Earth and universe appear to be of great age, does not imply that all we see came about purely as the result of random processes? Or that all the values humans hold in common -- justice, love -- are nothing but arbitrary constructs of our own minds, without absolute values? Scientists profess surprise when young people reject materialism and flock to all manner of New Age spiritual doctrines. Students can see perfectly well that science and technology lack soul and the core of humanity.

Stubbornness in what they are told to believe is driving students toward false choices. Cosmologist Ronald Mallett, in Kristine Larsen's interview in Mercury [May/June, p. 27], shared his experiences with students shying away from science because they felt it to threaten their faith. And speaking of bait-and-switch, observed facts can hardly serve as grounds for a moral view of the world.

VR: Science, at least, is grounded in matters not subject to argument. Experiments and observations can be replicated: There is nothing culturally relative about how gravity operates. We are all too keenly aware of our limitations. It is an odd paradox that our most exact and reproducible knowledge comes from the most dispassionate assessment of our own errors and limitations. Nobel laureate Richard Feynman expressed this in his own inimitable style: ``I am not trying to tell you what to do about cheating on your wife, or fooling your girlfriend, or something like that, when you're not trying to be a scientist, but just trying to be an ordinary human being. We'll leave those problems up to you and your rabbi. I'm talking about a specific, extra type of integrity that is not lying, but bending over backwards to show how you're maybe wrong, that you ought to have when acting as a scientist."

The scientific method, as poorly as it is usually communicated, is our only hope for recognizing our cultural preconceptions and biases from within. And its utility has been demonstrated beyond reproach. Even philosophers who deny objective reality seem to prefer using bridges and airplanes designed using Newtonian mechanics.

VF: Even Cardinal Bellarmine, facing Galileo in Rome, understood that the inductive reasoning that has served science so well can never yield absolute truth. Knowledge from induction, based on generalization from observations -- which is to say, everything that science tells us -- is partial, temporal, and cannot ever be said to be absolute. As finite beings, we can never know if we are in possession of some fragment of ultimate truth about the universe.

Working scientists seem to recognize quite well their limitations in scope. The science has proven mantra seems to issue more from apologists for science, as a kind of religion in itself: a view that claims for the scientific method a scope and implications that are by nature beyond its reach. Absolute knowledge must be based on direct, yes, supernatural, revelation. And even then, because we are finite and fallible, our understanding of such a revelation must be partial and subject to constant examination.

VR: The terrestrial environment, and the universe at large, certainly seem rather finely tuned for our needs. This we now understand in terms of the anthropic principle. If the universe had laws so different that we couldn't exist, we wouldn't be sitting here arguing about it. From a quantum-mechanical perspective, the issue is still open to healthy debate, but the old argument from design falls apart when we consider that no one could talk about cosmology in a universe that wasn't tuned to the needs of organisms.

VF: The argument from design -- that a creation implies a creator -- is practically vilified in philosophical circles, yet what is science doing except to find out how this all came to be? Many scientists talk with a straight face about self-organizing systems or potential yet unactualized universes, as if that lessens somehow the fundamental mystery of why there is something rather than nothing.

New discoveries in geophysics and biology, no less than astronomy, show myriad ways in which our world is set up to allow and cushion our existence. Consider the seemingly disparate phenomena as plate tectonics replenishing the metals available near the Earth's surface, a resonance in the carbon atom allowing these heavy elements to be synthesized in giant stars, the role of the Moon in stabilizing our axis over long times, and the very fact that the universe is old enough to have produced the Sun and planets. It all fairly screams at an overarching design.

VR: One must concede that reason in itself can provide no basis for life. Reason can give no motivation for doing anything at all, be it contemplating the universe or fighting disease. People need some kind of metaphysics, some guiding principle in life. And it must come from beyond logic and reason. This is what we have lost as many have striven to eradicate superstitious and fallacious beliefs.

VF: One can feel a certain attraction to the intellectual atmosphere of scholastic life in the late Middle Ages, possessing a unified world view in which all facets of spirit and intellect could pull in the same direction toward harmony with God and creation. Something is too often missing in religious life today. There is a feeling that science and reason are deceitful, to be avoided if one is to stay pure. This cannot be what we are made for. There must be some sort of unity possible.

VR: Recent history is replete with what-ifs that mark lost opportunities to heal this rift. What if American Christianity had not taken the anti-intellectual elements in American culture to extremes? What if the Pope had taken Galileo's arguments to heart and embraced them as new revelations of the glory of creation? What if Christian culture had maintained some of the Jewish respect for inquiry? And to be fair, what if the prominent apologists for Darwin hadn't been trying to get social mileage out of biological arguments?

VF: Recent history is replete with what-ifs that mark lost opportunities to heal this rift. What if Pope Urban hadn't been preoccupied with war in Europe and enforcing intellectual discipline against the Reformation? What if European upper-crust society hadn't been so disillusioned by war and turned almost completely against religion in the 20th century? And perhaps most relevant, what if fundamentalism hadn't become a political issue in the United States? After all, most Christians aren't really involved in this particular fight, according to the polls. It is a tragedy that the anti-intellectual legacy of American Protestantism means that ideas are hard to build across generations and often viewed with suspicion as some sort of alien infection.

VR: Science has broken us out of the ancient bowl of night and into an incomparably wider, richer world. This is one of the forces driving scientists to new discovery. If there is any moral imperative that the cosmos inspires, it must be to strive to know it, and ourselves; to appreciate its intricate and interconnected workings; to act as the eyes and brain of the universe. ``Hidden within every astronomical investigation, sometimes so deeply buried that the researcher himself is unaware of its presence, lies a kernel of awe."

VF: The Bible tell us that ``the heavens declare the glory.'' Deeper knowledge and appreciation of our universe can only deepen our understanding of its creator and out place within it. Carl Sagan put it well: ``Hidden within every astronomical investigation, sometimes so deeply buried that the researcher himself is unaware of its presence, lies a kernel of awe.

WILLIAM C. KEEL is an astronomy professor at the University of Alabama in Tuscaloosa. He works on galaxy evolution and structure. More information on his recent work can be found on the World Wide Web here . His email address is The author would like to thank Owen Gingerich, Keith Pavlischek, and Alan Stockton for comments on an earlier draft of this article.

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