C. S. Lewis on Evolution and Intelligent Design, Part 2

| By Michael L. Peterson

This blog series, adapted from this article inPerspectives on Science and Christian Faith, is a comprehensive study of the views of Christian author and apologist C. S. Lewis on the theory of evolution and the argument from intelligent design. In Part 1, Peterson outlines the classic approaches to natural theology and argues that while Lewis did embrace several lines of reasoning which implicitly or explicitly argue for an Intelligence beyond nature, none of these lines of reasoning are really “design-type” arguments. Today we begin to see why.

C. S. Lewis on Evolution and Intelligent Design, Part 2



The recent ID argument gets some support in the evangelical community because it taps into the conviction that “in some important sense” God is a Designer or Intelligent Agent behind the universe. This new argument, however, is not the first to go by the rubric of “intelligent design,” since design-type arguments have a long history, as noted in Part 1. In assessing the viability of all arguments from some orderly feature of the world to an Intelligence beyond the world, we must make some crucial distinctions. There are significant differences between traditional teleological or design arguments, on the one hand, and the new ID argument, on the other. These differences are reflected in their respective answers to two key questions: In what exact sense is God the Designer? And, what sorts of considerations, if any, legitimately point to a Designer? Although a comprehensive treatment of the intellectual history and logical structure of design-type arguments would review a generous handful of versions, here we will simply employ a two-fold classification: traditional teleological approaches and the much newer ID approach, as two very different ways of answering these questions.

Natural theology through the centuries includes a range of design-type arguments—from Aquinas’s reasoning to a Transcendent Intelligence as the best account of the teleology of natural objects, to Richard Swinburne’s contention that a Supremely Rational Mind is required to think and uphold natural laws.1 In 2004, the news broke that Antony Flew, one of the most famous atheistic philosophers of the twentieth century, had announced that he had come to embrace a more or less Deistic belief that there is a Supreme Being who intelligently structured the universe but neither interacts with it nor underwrites an afterlife. Soon thereafter, Flew’s book There Is a God: How the World’s Most Notorious Atheist Changed His Mind appeared and provided a lucid retelling of his intellectual journey—a journey shaped by engaging the findings of science with insights from the traditional teleological argument, the fine-tuning argument (including the anthropic principle), and the cosmological argument.2 Throughout the book, Flew repeatedly explains that his arguments for a Supreme Mind are distinctively philosophical in nature, grounded in philosophical reflections on recent scientific findings as well as on the scientific enterprise itself. Flew distinguishes his approach from misguided attempts to provide scientific arguments for a Supreme Mind. Francis Collins and John Polkinghorne, both severe critics of ID, wrote enthusiastic recommendations of Flew’s book.

Flew, who deceased on April 8, 2010, is also interesting here because of his exposure to Lewis during the 1950s when Lewis was chair of the Socratic Club at Oxford. Flew’s approach to the present subject reflects a classical outlook similar to Lewis’s: a deep respect for the enterprise of science and informed awareness of the phenomena it studies, combined with the insight that both science and its important findings require philosophical explanation. Why does physical nature conform to mathematically precise laws? Why are there conscious minds which perceive this? And why does life seem inherently end-directed? Flew came to answer these sorts of philosophical questions by positing a Supreme Mind. ID, by contrast, is critical of mainstream science and seeks to develop an argument for a Transcendent Intelligence from within its remodeled version of science, as we shall soon see. One last fascinating point concerning Flew’s change of mind: from his newly adopted position of Deism, he considers Christianity to be the most rationally respectable living religion. He even includes in his book an appendix written by N. T. Wright, Bishop of Durham, presenting reasons why orthodox Christian claims about the historical Jesus are credible.

ID views itself as reviving and updating the eighteenth-century argument for God which assumes that science can discover traces of a designing intelligence in the natural world. William Dembski, founder and leading spokesperson for ID, states that “God’s design is … accessible to scientific inquiry.” The ID movement claims to work within the field of biology (specifically, biochemistry) in order to show that an Intelligence above nature is a better explanation of certain phenomena than is Evolution. Dembski says that mainstream biology operates on the evolutionary assumption that complex life forms developed gradually from simpler forms over long periods of time as natural selection winnows through genetic variations which occur by blind chance. This means that biological complexity should be reducible to simpler components—and we do, indeed, have such reducible complexity in a wide variety of organic forms. Yet, some special cases, Dembski claims, are “irreducibly complex.” Irreducibly complex forms have parts which themselves have complete and complex functions of their own, making it highly unlikely that all independently working parts could come together through evolutionary processes. Dembski writes: “The irreducible complexity of … biochemical systems counts powerfully against the Darwinian mechanism and indeed against any naturalistic evolutionary mechanism proposed to date.”3 Dembski and his allies, such as Michael Behe, have advanced several much-discussed examples of irreducible complexity— such as the bacterial flagellum, the blood-clotting mechanism, and the eye.4

IDers formulate statistical arguments to show how mathematically improbable it is that random genetic variations plus natural selection, even over great spans of time, could result in the highly complex structures they identify. These arguments involve lots of zeroes after a decimal point. Think of this strategy in terms of probabilities in poker. The probability of being dealt a royal flush on one hand is 0.000002. The probability of being dealt two royal flushes in a row is this number squared (0.0000022 or 0.00000000004). If a person keeps getting dealt royal flushes, we have to suspect cheating, which is a sort of “intelligent design” in cards.

Back to ID calculations: the probability of irreducibly complex forms being brought about by evolution is argued to be infinitesimally small, making ID the only reasonable alternative. Behe cites the blood-clotting mechanism as a case in point. Animals with blood-clotting cascades have about 10,000 genes, and each gene has three pieces. This totals 30,000 gene pieces. TPA (tissue plasminogen activator) has four different types of domains. As Behe argues, the odds that the right pieces can come together for blood-clotting to occur are therefore supposed to be 1 in 30,0004 (or 0.0000000000000000012407). Behe estimates that it would take about a thousand billion years before blood-clotting occurred, whereas the earth is only about 6 billion years old, and even the simplest life forms did not occur until perhaps about 3 billion years ago.5 So, blood-clotting represents too many royal flushes in a row, so to speak. Behe’s claim, then, is that natural laws plus time simply cannot account for the phenomenon. According to the new ID argument, it is much more probable that an intelligence beyond nature instantaneously brought about this fully functioning mechanism. In effect, blood-clotting becomes a candidate for special creation, a miracle. Now, IDers will not say that the Intelligent Being behind nature is God, but it is clear that they think they are establishing two attributes of God: (1) intelligence and (2) the power to act on intelligent planning.


1. Aquinas, Summa Theologica, trans. Fathers of the English Dominican Province (Westminster, MD: Christian Classics, 1948), Question 2, Art 3. Richard Swinburne, The Existence of God (Oxford: Oxford University Press, 2004), 153–91. See also Laura Garcia, “Teleological and Design Arguments” in A Companion to Philosophy of Religion, 2d ed., ed. Charles Taliaferro, Paul Draper, and Philip L. Quinn (Oxford: Wiley-Blackwell, 2010), 375–84.

2. Antony Flew, There Is a God: How the World’s Most Notorious Atheist Changed His Mind (New York: HarperOne, 2007).

3. William Dembski, Intelligent Design: The Bridge between Science and Theology (Downers Grove, IL: InterVarsity Press, 1999), 148.

4. Critics of ID have provided sound scientific explanations for these phenomena without reference to a transcendent intelligence. See, for example, Philip Kitcher, Living with Darwin: Evolution, Design, and the Future of Faith (New York: Oxford University Press, 2007); Francisco Ayala, Darwin and Intelligent Design (Minneapolis, MN: Fortress Press, 2006) and Darwin’s Gift to Science and Religion (Washington, DC: Joseph Henry Press, 2007). It is particularly fascinating to account for the significant weight that the mapping of the Human Genome lends to the confirmation of biological evolution. Francis Collins, Director of the Human Genome Project in the 1990s and now Director of the NIH, who was greatly influenced in his faith by Lewis’s Mere Christianity, makes the scientific case for evolution based on the amazing accomplishments of research in molecular biology in recent years. See Collins’s The Language of God: A Scientist Presents Evidence for Belief (New York: Simon and Schuster, 2006). Collins founded the BioLogos Foundation to promote engagement of science and faith as well as to help navigate various errors committed by both secular and religious perspectives (http://biologos.org, last accessed September 22, 2010).

5. Michael Behe, Darwin’s Black Box: The Biochemical Challenge to Evolution (New York: Free Press, 1996), 94.


About the Author

Michael L. Peterson

Michael L. Peterson is professor of philosophy at Asbury University. He is also managing editor of Faith and Philosophy: Journal of the Society of Christian Philosophers. His books include Reason and Religious Belief (Oxford); God and Evil(Westview); With All Your Mind: A Christian Philosophy of Education (Notre Dame); and Evil and the Christian God(Baker). He has produced multiple edited volumes and journal articles.