Why Darwin Matters

by Michael Shermer

  WHY SCIENCE CANNOT CONTRADICT RELIGION

  The sciences of observation describe and measure the multiple manifestations of life with increasing precision and correlate them with the time line. The moment of transition to the spiritual cannot be the object of this kind of observation.

  —Pope John Paul II, Truth Cannot Contradict Truth, 1996

  In considering the religious implications of the theory of evolution, it is illuminating to consider in greater depth the religious attitudes of the theory’s architect. Charles Darwin’s thoughts and feelings on how science and religion might be reconciled—in his own home and in the larger society—were complex and evolved over time.

  Darwin matriculated at Cambridge University in theology, but he did so only after abandoning his medical studies at Edinburgh University because of his distaste for the barbarity of surgery. Darwin’s famous grandfather Erasmus, and his father Robert, both physicians by trade who were deeply schooled in natural history, were confirmed freethinkers, so there was no doctrinaire pressure on the young Charles to choose theology.

  In point of fact, Darwin’s selection of theology as his primary course of study allowed him to pursue his passion for natural history through the academic justification of studying “natural theology”—he was far more interested in God’s works (nature) than God’s words (the Bible). Besides, theology was one of only a handful of professions that a gentleman of the Darwin family’s high social position in the landed gentry of British society could choose. Finally, although Darwin belonged to the Church of England, membership was expected of someone in his social class.

  Still, Darwin’s religiosity was not entirely utilitarian. He began and ended his five-year voyage around the world as a creationist, and he regularly attended religious services on board the Beagle and even during some land excursions in South America. It was only upon his return home that the loss of his faith came about, and that loss happened gradually—even reluctantly—over many years.

  Darwin’s God and the Devil’s Chaplain

  Nagging doubts about the nature and existence of the deity chipped away at Darwin’s faith as a result of his studies of the natural world, particularly many of his observations of the cruel nature of the relationship between predators and prey. “What a book a Devil’s Chaplain might write on the clumsy, wasteful, blundering low & horridly cruel works of nature!” Darwin lamented in an 1856 letter to his botanist mentor Joseph Hooker. In 1860 he wrote to his American colleague, the Harvard biologist Asa Gray, about a species of wasp that paralyzes its prey (but does not kill it), then lays its eggs inside the paralyzed insect so that upon birth its offspring can feed on live flesh. “I cannot persuade myself that a beneficent God would have designedly created the Ichneumonidae with the express intention of their feeding within the living bodies of Caterpillars, or that a cat should play with mice. Not believing this,” he reflected, “I see no necessity in the belief that the eye was expressly designed.”1

  Pain and evil in the human world made Darwin doubt even more. “That there is much suffering in the world no one disputes,” he wrote to a correspondent. “Some have attempted to explain this with reference to man by imagining that it serves for his moral improvement. But the number of men in the world is as nothing compared with that of all other sentient beings, and they often suffer greatly without any moral improvement.” Which is more likely, that pain and evil are the result of an all-powerful and good God, or the product of uncaring natural forces? “The presence of much suffering agrees well with the view that all organic beings have been developed through variation and natural selection.”2 The death of Darwin’s beloved ten-year-old daughter Anne put an end to whatever confidence he had in God’s benevolence, omniscience, and even existence. According to the great Darwin scholar and biographer Janet Browne, “this death was the formal beginning of Darwin’s conscious dissociation from believing in the traditional figure of God.”3

  Throughout most of his professional career, however, Darwin eschewed the God question entirely, choosing instead to focus on his scientific studies. Toward the end of his life Darwin received many letters querying him on his religious attitudes. His long silence gave way to a few revelations. In one letter dated 1879, just three years before he died, Darwin finally expressed his beliefs: “In my most extreme fluctuations I have never been an Atheist in the sense of denying the existence of God. I think that generally (and more and more as I grow older), but not always, that an Agnostic would be the more correct description of my state of mind.”4

  A year later, Darwin clarified his thinking. The British socialist Edward Aveling had compiled a volume entitled The Student’s Darwin, on the implications of evolutionary theory for religious thought, and Aveling wanted Darwin’s endorsement. The book had a militant antireligious flavor and unabashedly radical atheist tone that Darwin disdained, and he declined the request, elaborating his reason with his usual flair for quotable maxims: “It appears to me (whether rightly or wrongly) that direct arguments against christianity & theism produce hardly any effect on the public; & freedom of thought is best promoted by the gradual illumination of men’s minds which follow[s] from the advance of science. It has, therefore, been always my object to avoid writing on religion, & I have confined myself to science.” He then appended an additional hint about a personal motive, noting “I may, however, have been unduly biased by the pain which it would give some members of my family, if I aided in any way direct attacks on religion.”5 Darwin’s wife Emma was a deeply religious woman, and out of respect for her he kept the public side of his religious skepticism in check, an admirable feat of self-discipline by a man of high moral character.

  Conflict or Compromise?

  Was Darwin’s approach to science and religion healthy? Was it logical? Is it possible to reconcile religious belief with scientific thinking? The answer one gives to these questions determines the attitude one takes to the relationship of science and religion: conflict, harmony, or indifference. And if we could find some level at which agreement could be reached between all sides of the debate, much of the angst and rancor in today’s culture over this divide would subside. I have made such an attempt in the form of a three-tiered model of the possible relationships between science and religion.

  1. The Conflicting-Worlds Model. This “warfare” approach holds that science and religion are mutually exclusive ways of knowing, one being right and the other wrong. In this view, the findings of modern science are always a potential threat to one’s faith and thus they must be carefully vetted against religious truths before acceptance; likewise, the tenets of religion are always a potential threat to science and thus they must be viewed with skepticism and cynicism. The conflicting-worlds model is embraced by extremists on both sides of the divide. Young Earth creationists, who insist that all scientific findings must correlate perfectly with their own (often literal) reading of Genesis, retain a suspicious hostility toward science, while militant atheists cannot imagine how religion could contribute anything positive to human knowledge or social interaction.6

  2. The Same-World Model. More conciliatory in its nature than the conflicting-worlds model, this position holds that science and religion are two ways of examining the same reality, and that as science progresses to a deeper understanding of the natural world, it will reveal that many ancient religious tenets are true. The same-world model is embraced by many mainstream theologians, religious leaders, and believing scientists who prefer a more flexible cognitive approach to science and religion, allowing them to read biblical passages metaphorically. For example, the “days” in the Genesis creation story may represent geological epochs of great length. The theology of Pope John Paul II as well as that of the Dalai Lama fall squarely into this tier, as they argue that science and religion can work together toward the same goal of understanding the universe and our place in it.7

  3. The Separate-Worlds Model. On this tier, science and religion are neither in conflict nor in agreement but are, in St
ephen Jay Gould’s phrase, “nonoverlapping magisteria” (NOMA).8 Before science began its ascent four centuries ago, religion provided an explanation for the natural world in the form of various cosmogony myths. Since the scientific revolution, however, science has taken over the job of explaining the natural world, making obsolete ancient religious sagas of origins and creation. Yet religion thrives in the modern age because it still serves a useful purpose as an institution for social cohesiveness and as a guide to finding personal meaning and spirituality, a function that science has left largely untouched.

  God as a Null Hypothesis

  Can the conflicting-worlds and same-world models of science and religion work? Frankly, they cannot. To accept science requires accepting one of its central tenets: that a claim must be falsifiable; that is, there has to be some way to test the claim and show that it is false. If it cannot be proven false, then it cannot be proven true. The philosopher of science Karl Popper made the definitive statement on the matter: “I shall not require of a scientific system that it shall be capable of being singled out, once and for all, in a positive sense; but I shall require that its logical form shall be such that it can be singled out, by means of empirical tests, in a negative sense: it must be possible for an empirical scientific system to be refuted by experience.”9

  On the question of God’s existence, what criteria for falsifiability could we establish? If we want to make God’s existence a scientific question that can be decided by empirical evidence, we would need to establish an operational definition of God and quantifiable criteria by which we can arrive at a testable conclusion of the deity’s existence. In experimental science we begin by accepting the “null hypothesis” that whatever is being tested does not exist or has no effect. If the evidence is significant, we may “reject the null hypothesis” and conclude that our subject does exist or has some effect. In subjecting God to experimental science, we would have to begin by accepting the null hypothesis that He does not exist, and then assess the evidence to determine if it is significant enough to reject the null hypothesis.

  The claim that intercessory prayer (in which one prays for God to intercede) can effect healing, for example, is testable. If true, it would imply that the deity is acting in our world in some measurable fashion. However, the handful of studies that have found significant differences between the prayed-for experimental group and the not-prayed-for control group have had deep methodological flaws (such as not controlling for age, socioeconomic class, or condition of health before entering the hospital, all of which influence recovery).10 To date, strictly controlled prayer studies, as a testable hypothesis of God’s divine providence, have failed the test.

  The numerous other claims by Intelligent Design creationists that science supports belief in God also fall dramatically short of the empirical standards of science. Based on these results, were we to take a strictly scientific approach to the God question, we would have to reject the God hypothesis. Are theists willing to go this far when they attempt to use science to support their religious tenets? I doubt it, which is precisely why the separate-worlds model is the best approach to take for theists.

  A Is A: Why Science Cannot Contradict Religion

  Darwin’s separate-worlds approach to science and religion worked well for him in both his home and his culture, but it still leaves open the deeper question about whether one can logically believe in God and accept evolution. That is, if carried to its logical conclusion, does the theory of evolution preclude belief in God? This is where the epistemological rubber meets the hypothetical road.

  Belief in God depends on religious faith. Acceptance of evolution depends on empirical evidence. This is the fundamental difference between religion and science. If you attempt to reconcile and combine religion and science on questions about nature and the universe, and if you push the science to its logical conclusion, you will end up naturalizing the deity; for any question about nature, if your answer is “God did it,” a scientist will ask such questions as “How did God do it? What forces did God use? What forms of matter and energy were employed in the creation process?” The end result of this inquiry can only be natural explanations for all natural phenomena. What place, then, for God?

  One could logically argue that God is the laws and forces of nature, but this is pantheism and not the type of personal God in which most people profess belief. One could also reasonably argue that God created the universe and life using the laws and forces of nature, but it leaves us with those nagging scientific questions: Which laws and forces were used, and in what manner were they used? For that matter, how did God create the laws and forces of nature? A scientist would be curious to know God’s recipe for, say, gravity. Likewise, it is a legitimate scientific question to ask: What made God, and how was God created? How do you make an omniscient and omnipotent being?

  The theists’ response to this line of inquiry is that God needs no cause—God is a causeless cause, an unmoved mover. But why should God not need a cause? If the universe is everything that is, ever was, or ever shall be, God must be within the universe or be the universe. In either case, God would himself need to be caused, and thus the regress to a first cause leads back to the question: What caused God? And if God does not need to be caused, then clearly not everything in the universe needs to be caused. Maybe the initial creation of the universe was its own first cause and the Big Bang was the prime mover.

  The problem with all of these attempts at blending science and religion may be found in a single principle: A is A. Or: Reality is real. To attempt to use nature to prove the supernatural is a violation of A is A. It is an attempt to make reality unreal. A cannot also be non-A. Nature cannot also be non-nature. Naturalism cannot also be supernaturalism.

  Pope John Paul II, whose theology was influenced by Aristotle and Aquinas, two of the greatest minds in the history of philosophy and theology, understood this fundamental principle and argued the point in his 1996 encyclical, Truth Cannot Contradict Truth. The only way science and religion can be reconciled, particularly in the context of the evolution-creation controversy, is if body and soul are ontologically distinct; that is, if they exist in different realities. Evolution created the body, God created the soul:

  With man, then, we find ourselves in the presence of an ontological difference, an ontological leap, one could say. Consideration of the method used in the various branches of knowledge makes it possible to reconcile two points of view which would seem irreconcilable. The sciences of observation describe and measure the multiple manifestations of life with increasing precision and correlate them with the time line. The moment of transition to the spiritual cannot be the object of this kind of observation, which nevertheless can discover at the experimental level a series of very valuable signs indicating what is specific to the human being. But the experience of metaphysical knowledge, of self-awareness and self-reflection, of moral conscience, freedom, or again, of aesthetic and religious experience, falls within the competence of philosophical analysis and reflection, while theology brings out its ultimate meaning according to the Creator’s plans.11

  Believers can have both religion and science as long as there is no attempt to make A non-A, to make reality unreal, to turn naturalism into supernaturalism. Thus, the most logically coherent argument for theists is that God is outside time and space; that is, God is beyond nature—super nature, or supernatural—and therefore cannot be explained by natural causes. God is beyond the dominion of science, and science is outside the realm of God.

  WHY CHRISTIANS AND

  CONSERVATIVES

  SHOULD ACCEPT EVOLUTION

  I see no good reason why the views given in this volume should shock the religious feeling of any one. It is satisfactory, as showing how transient such impressions are, to remember that the greatest discovery ever made by man, namely, the law of the attraction of gravity, was also attacked by Leibnitz, “as subversive of natural, and inferentially of revealed, religion.” A celebrated author and divin
e has written to me that “he has gradually learnt to see that it is just as noble a conception of the Deity to believe that He created a few original forms, capable of self-development into other and needful forms, as to believe that He required a fresh act of creation to supply the voids caused by the actions of His laws.”

  —Charles Darwin, 2nd edition of On the Origin of Species, 1860

  During the cultural brouhaha whipped up by the media frenzy over President George W. Bush’s 2005 comments on Intelligent Design and evolution, a reporter from Time magazine solicited my opinion about whether one can believe in both God and evolution.

  I replied that, empirically speaking, apparently so, because lots of people do—a 1996 survey found that 39 percent of American scientists profess belief in God, and a 1997 poll found that 99 percent of American scientists accept the theory of evolution. More recently, preliminary results from a long-term survey of 1,600 scientists from twenty-one elite universities revealed that over half consider themselves “moderately spiritual” to “very spiritual,” and about a third hold formal religious affiliations.1 So either a third of my colleagues live in a cognitive fantasyland of logic-tight compartments, or there is a way to find that separate-worlds harmony between science and religion.