Pius lashes out, in turn, at various external enemies of the Church: pantheism, existentialism, dialectical materialism, historicism, and, of course and preeminently, communism. He then notes with sadness that some well-meaning folks within the Church have fallen into a dangerous relativism—“a theological pacifism and egalitarianism, in which all points of view become equally valid”—in order to include those who yearn for the embrace of Christian religion, but do not wish to accept the particularly Catholic magisterium.
Pius first mentions evolution to decry a misuse by overextension among zealous supporters of the anathematized “isms”:
Some imprudently and indiscreetly hold that evolution … explains the origin of all things … Communists gladly subscribe to this opinion so that, when the souls of men have been deprived of every idea of a personal God, they may the more efficaciously defend and propagate their dialectical materialism.
Pius presents his major statement on evolution near the end of the encyclical, in paragraphs 35 through 37. He accepts the standard account of NOMA and begins by acknowledging that evolution lies in a difficult area where the domains press hard against each other. “It remains for US now to speak about those questions which, although they pertain to the positive sciences, are nevertheless more or less connected with the truths of the Christian faith.”3
Pius then writes the well-known words that permit Catholics to entertain the evolution of the human body (a factual issue under the magisterium of science), so long as they accept the divine creation and infusion of the soul (a theological notion under the magisterium of religion).
The Teaching Authority of the Church does not forbid that, in conformity with the present state of human sciences and sacred theology, research and discussions, on the part of men experienced in both fields, take place with regard to the doctrine of evolution, in as far as it inquires into the origin of the human body as coming from pre-existent and living matter—for the Catholic faith obliges us to hold that souls are immediately created by God.
I had, up to here, found nothing surprising in Humani Generis, and nothing to relieve my puzzlement about the novelty of Pope John Paul’s 1996 statement. But I read further and realized that Pope Pius had said more about evolution, something I had never seen quoted, and something that made John Paul’s statement most interesting indeed. In short, Pius forcefully proclaimed that while evolution may be legitimate in principle, the theory, in fact, had not been proven and might well be entirely wrong. One gets the strong impression, moreover, that Pius was rooting pretty hard for a verdict of falsity. Continuing directly from the last quotation, he advises us about the proper study of evolution:
However, this must be done in such a way that the reasons for both opinions, that is, those favorable and those unfavorable to evolution, be weighed and judged with the necessary seriousness, moderation and measure … Some, however, rashly transgress this liberty of discussion, when they act as if the origin of the human body from pre-existing and living matter were already completely certain and proved by the facts which have been discovered up to now and by reasoning on those facts, and as if there were nothing in the sources of divine revelation which demands the greatest moderation and caution in this question.
To summarize, Pius accepts the NOMA principle in permitting Catholics to entertain the hypothesis of evolution for the human body so long as they accept the divine infusion of the soul. But he then offers some (holy) fatherly advice to scientists about the status of evolution as a scientific concept: the idea is not yet proven, and you all need to be especially cautious because evolution raises many troubling issues right on the border of my magisterium. One may read this second theme of advice-giving in two rather different ways: either as a gratuitous incursion into a different magisterium, or as a helpful perspective from an intelligent and concerned outsider.
In any case, this rarely quoted second claim (that evolution remains both unproven and a bit dangerous)—and not the familiar first argument for NOMA (that Catholics may accept the evolution of the body so long as they embrace the creation of the soul)—defines the novelty and the interest of John Paul’s recent statement.
John Paul begins by summarizing Pius’s older encyclical of 1950, and particularly by reaffirming NOMA—nothing new here, and no cause for extended publicity:
In his encyclical Humani Generis (1950), my predecessor Pius XII had already stated that there was no opposition between evolution and the doctrine of the faith about man and his vocation.
The novelty and news value of John Paul’s statement lies, rather, in his profound revision of Pius’s second and rarely quoted claim that evolution, while conceivable in principle and reconcilable with religion, can cite little persuasive evidence in support, and may well be false. John Paul states—and I can only say amen, and thanks for noticing—that the half-century between Pius surveying the ruins of World War II and his own pontificate heralding the dawn of a new millennium has witnessed such a growth of data, and such a refinement of theory, that evolution can no longer be doubted by people of goodwill and keen intellect:
Pius XII added … that this opinion [evolution] should not be adopted as though it were a certain, proven doctrine … Today, almost half a century after the publication of the encyclical, new knowledge has led to the recognition of the theory of evolution as more than a hypothesis. It is indeed remarkable that this theory has been progressively accepted by researchers, following a series of discoveries in various fields of knowledge. The convergence, neither sought nor fabricated, of the results of work that was conducted independently is in itself a significant argument in favor of the theory.
In conclusion, Pius had grudgingly admitted evolution as a legitimate hypothesis that he regarded as only tentatively supported and potentially (as he clearly hoped) untrue. John Paul, nearly fifty years later, reaffirms the legitimacy of evolution under the NOMA principle, but then adds that additional data and theory have placed the factuality of evolution beyond reasonable doubt. Sincere Christians may now accept evolution not merely as a plausible possibility, but also as an effectively proven fact. In other words, official Catholic opinion on evolution has moved from “say it ain’t so, but we can deal with it if we have to” (Pius’s grudging view of 1950) to John Paul’s entirely welcoming “it has been proven true; we always celebrate nature’s factuality, and we look forward to interesting discussions of theological implications.” I happily endorse this turn of events as gospel—literally, good news. I represent the magisterium of science, but I welcome the support of a primary leader from the other major magisterium of our complex lives. And I recall the wisdom of King Solomon: “As cold waters to a thirsty soul, so is good news from a far country” (Proverbs 25:25).
2. THE CLERIC WHO OUT-NEWTONED NEWTON. If NOMA did not work, and religion really did demand the suppression of important factual data at key points of contradiction with theological dogma, then how could the ranks of science include so many ordained and devoted clergymen at the highest level of respect and accomplishment—from the thirteenth-century Dominican bishop Albertus Magnus, the teacher of Thomas Aquinas and the most cogent medieval writer on scientific subjects; to Nicholas Steno, who wrote the primary works of seventeenth-century geology and also became a bishop; to Lazzaro Spallanzani, the eighteenth-century Italian physiologist who disproved, by elegant experiments, the last serious arguments for spontaneous generation of life; to the Abbé Breuil, our own century’s most famous student of paleolithic cave art?
In the conventional view of warfare between the magisteria, science began its inevitable expansion at religion’s expense during the late seventeenth century, a remarkable period known to historians as “the scientific revolution.” We all honor the primary symbol of the new order, Isaac Newton, whose achievements were captured by his contemporary Alexander Pope in the most incisive of all epitomes:
Nature and nature’s laws lay hid in night
God said “Let Newton be,” and all was light.
/> Many people are then surprised to discover—although the great man made no attempt to disguise his commitments—that Newton (along with all other prominent members of his circle) remained an ardent theist. He spent far more time working on his exegeses of the prophecies of Daniel and John, and on his attempt to integrate biblical chronology with the histories of other ancient peoples, than he ever devoted to physics.
Scientists with strong theological commitments have embraced NOMA in several styles—from the argument of “God as clockwinder” generally followed by Newton’s contemporaries, to the “bench-top materialism” of most religious scientists today (who hold that “deep” questions about ultimate meanings lie outside the realm of science and under the aegis of religious inquiry, while scientific methods, based on the spatiotemporal invariance of natural law, apply to all potentially resolvable questions about facts of nature). So long as religious beliefs do not dictate specific answers to empirical questions or foreclose the acceptance of documented facts, the most theologically devout scientists should have no trouble pursuing their day jobs with equal zeal.
The first commandment for all versions of NOMA might be summarized by stating: “Thou shalt not mix the magisteria by claiming that God directly ordains important events in the history of nature by special interference knowable only through revelation and not accessible to science.” In common parlance, we refer to such special interference as “miracle”—operationally defined as a unique and temporary suspension of natural law to reorder the facts of nature by divine fiat. (I know that some people use the word “miracle” in other senses that may not violate NOMA—but I follow the classical definition here.) NOMA does impose this “limitation” on concepts of God, just as NOMA places equally strong restrictions upon the imperialistic aims of many scientists (particularly in suppressing claims for possession of moral truth based on superior understanding of factual truth in any subject).
All consensuses of this sort develop slowly, and from inchoate beginnings before later distinctions become clarified and established. In the early days of modern science, the conceptual need to place miracles outside this developing magisterium had not been fully articulated, and the issue generated much discussion, eventually resolved as outlined above (with God’s direct action in the creation of living species persisting as a last stronghold, long after miraculous action has been abandoned for all the rest of nature’s factual realm). Ironically, Newton himself held a fairly lenient view on the admissibility of miracles to scientific discourse. He certainly recognized the explanatory advantages of God’s working within His own established laws, but he regarded as unnecessarily presumptuous any attempts by students of the natural order thus to confine God’s range of potential action. If God wished to suspend these laws for a moment of creative interference, then He would do exactly as He wished, and scientists would have to pursue the task of explanation as best they could.
Interestingly, the sharpest opposition to such latitude within the developing magisterium of science, and the strongest argument for defining miracles as strictly outside the compass of scientific inquiry, arose from the most prominent professional cleric within Newton’s orbit of leading scientists, the same Reverend Thomas Burnet who graced our first chapter. This irony of a clergyman’s firmest support for NOMA, in direct opposition to Newton’s looser view, should convince us that the magisteria need not exist in conflict, and that a committed theologian can also operate as an excellent and equally devoted scientist.
Newton, who had just read his friend’s Sacred Theory of the Earth, wrote to Burnet in January of 1681, stating his praise but also raising a few critiques. In particular, Newton argued that the problem of fitting God’s initial creative work into a mere six days might be solved by supposing that the earth then rotated much more slowly, producing “days” of enormous length. Burnet wrote an impassioned letter in immediate response:
Your kindness hath brought upon you the trouble of this long letter, which I could not avoid seeing you have insisted upon … the necessity of adhering to Moses his Hexameron as a physical description … To show the contrary … hath swelled my letter too much. [A hexameron is a period of six days, and Burnet uses the charmingly archaic form of the genitive case, “Moses his Hexameron,” where we would now employ an apostrophe and write Moses’ Hexameron.]
Burnet himself did not find the days of Genesis troubling because he had long favored an allegorical interpretation of these passages and held, in any case, that the concept of a “day” could not be defined before the sun’s creation on the fourth day of the Genesis sequence. But he rejected Newton’s exegesis for a different reason: he feared that Newton would not be able to devise a natural explanation for the subsequent speeding up of the earth’s rotation to modern days of twenty-four hours—and that his friend would therefore want to invoke a supernatural explanation. Burnet wrote to Newton: “But if the revolutions of the earth were thus slow at first, how came they to be swifter? From natural causes or supernatural?” (Burnet also raised other objections to Newton’s reading: those long early days would stretch the lives of the patriarchs even beyond the already problematical 969 of Methuselah; moreover, although animals would have enjoyed the long, sunny hours of daylight, the extended nights might have become unbearable: “If the day was thus long what a doleful night would there be.”)
Newton responded directly to Burnet’s methodological concerns, for he knew that his friend wished to avoid all arguments based on miracle in science—an issue far more important than the particular matter of early day lengths. He therefore wrote, confirming Burnet’s worst fear:
Where natural causes are at hand God uses them as instruments in his works, but I do not think them alone sufficient for the creation and therefore may be allowed to suppose that amongst other things God gave the earth its motion by such degrees and at such times as was most suitable to the creatures.
Newton also responded to Burnet’s worry about those long nights and their impact on early organisms: “And why might not birds and fishes endure one long night as well as those and other animals endure many in Greenland?”
Newton, one of the smartest of men in all our history, surely scored a point over Burnet in his retort about life above the Arctic Circle. Mark one for the polar bears (and another for the little-known penguins at the other end). But I think that we must grant Burnet the superior argument for a methodological claim now regarded as crucial to the definition of science: the status of miracles as necessarily outside this magisterium. The cleric, not the primary icon of modern science, offered a more cogent defense for basic modes of procedure in achieving fruitful answers. Mark one for NOMA.
2 The rest of this section on papal views about evolution has been adapted from an essay previously published in Leonardo’s Mountain of Clams and the Diet of Worms (Crown, 1998).
3 Interestingly, the main thrust of these paragraphs does not address evolution in general, but lies in refuting a doctrine that Pius calls “polygenism,” or the notion of human ancestry from multiple parents—for he regards such an idea as incompatible with the doctrine of original sin, “which proceeds from a sin actually committed by an individual Adam and which, through generation, is passed on to all and is in everyone as his own.” In this one instance, Pius may be trangressing the NOMA principle—but I cannot judge, for I do not understand the details of Catholic theology and therefore do not know how symbolically such a statement may be read. If Pius is arguing that we cannot entertain a theory about derivation of all modern humans from an ancestral population rather than through an ancestral individual (a potential fact) because such an idea would question the doctrine of original sin (a theological construct), then I would declare him out of line for letting the magisterium of religion dictate a conclusion with the magisterium of science.
Coda and Segue
J. S. HALDANE (1860–1936), A GREAT Scottish physiologist and deeply religious man (also the father of J. B. S. Haldane, the even more famous evolutionary
biologist who tended to radicalism in politics and atheism in theology), delivered the Gifford Lectures, a series dedicated to exploring the relationships between science and philosophy, at the University of Glasgow in 1927. Haldane devoted his lecture on “the sciences and religion” to the optimal solution of NOMA, and its central implications for religious thinkers on the subject of miracles and explanations of the natural world. Haldane began:
It is often supposed that the sciences … are essentially incompatible with religion. At present, this is a widespread popular belief for which there seems at first sight to be a substantial basis; and certainly this belief is common among scientific men themselves, although they may say little about it, out of respect for those who do hold sincere religious beliefs and whose lives they admire.
Haldane then locates the major barrier to NOMA in confusion of all forms of religious belief with the particular claim—which does mix the magisteria in contention and would therefore preclude NOMA—that much of material nature has been constructed by miracles inaccessible in principle to scientific study:
To those who believed that religion is dependent on a belief in supernatural intervention it seemed to be dying the death of other superstitions. Yet as a matter of fact religion continued to appeal to men as strongly as before, or perhaps more strongly.… I think that [I can] make clear the underlying explanation of this. If my reasoning has been correct, there is no real connection between religion and the belief in supernatural events of any sort or kind.
Finally, Haldane insists that this attitude toward miracles flows from his own deep and active commitment to religion, and not from any protective attitude toward his own magisterium of science: