Broadly speaking, natural theology concerns everything that can be known about God apart from divine special revelation. This typically amounts to one or another argument for God from some particular aspect of the world. For example, (1) natural human desires have ends that satisfy them—for hunger, food; thirst, water; etc. (2) Humans seem naturally to desire a happiness this world cannot satisfy. (3) Therefore, it is reasonable to think there is an end for humans beyond this world. (4) Only the idea of life with God seems to satisfy this desire. (5) Therefore, it is reasonable to believe there is a God humans were meant to enjoy. King David, Plato, Aristotle, Paul of Tarsus, Anselm, Aquinas, and Kant, to name a few, all gave similar arguments. The line of thought follows a rich and developed history. Today Contemporary Arguments in Natural Theology tries to bring that history to the present. Eighteen essays offer the latest iteration of many of the classical arguments for God’s existence as well as a number of new ones from biology, mathematics, and cosmology.
A summary of three of the essays provides a good introduction to the book.
In the opening essay, Joshua Rasmussen makes “The Argument from Contingency.” He starts with a simple guiding question: Why? As he points out, whenever anything happens—whatever that might be—a possible explanation can be expected. In other words, the Why? can be answered. For instance, lightning can explain a forest fire, or the Rubicon can explain how Caesar became dictator of Rome. Every time there seems to be some greater context that can make sense of things. But this line of thinking goes awry when applied to reality as a whole. When all of reality is lumped together, there can no longer be an external explanation; by definition, all of reality already includes every other thing or context within it. Faced with this conundrum, Rasmussen proposes his Foundation Theory. He contends that the only way to explain all of reality is if it already includes within it some necessary, foundational layer of existence that upholds and explains the rest. The essay puts forward two proofs for the existence of this layer. Both come down to an argument from contingency. The idea is that because a possible explanation of contingent things can be expected and because that explanation cannot ultimately be another contingent thing, then there must be something that exists necessarily, a foundational existence. After responding to a number of objections, Rasmussen concludes with an exploration of what further can be known about this layer based on its necessary existence. He puts forward a number of proofs to demonstrate that it must also be independent, eternal, unlimited, unsurpassable in power, and supreme. By the end, Rasmussen all but reasons to what might be commonly called God.
Chapter seven covers “The Moral Argument.” C.S. Evans and Trinity O’Neill introduce their essay with a line from The Brothers Karamazov: “Without God everything is permitted.” The rest of the essay effectively works this phrase backwards to see if it actually maps onto reality. Evans and O’Neill want to ask whether everything really is permitted and if God is needed to explain things if they’re not. Is everything permitted? Evans and O’Neill’s answer is somewhat surprising. Considering the genealogical theory of morals Friedrich Nietzsche put forward, they concede it is at least possible to deny that there are any binding moral obligations; nevertheless, they point out that denying and avoiding such obligations are two different things, e.g., the same person who denies objective moral duties also objects to being robbed. Ideas of right and wrong continue to reassert themselves in everyday experience. So, while objective morals may be doubted, Evans and O’Neill conclude they are nonetheless reasonable and attested to in everyday moral experience. Is God needed to explain these binding moral obligations? The essay considers four alternative accounts of morality that try to explain moral obligations without God. To give one example, binding moral obligations are just brute facts. In this account, objective moral duties are simply facts of the universe. They exist like the world without need of any further explanation. Evans and O’Neill again concede the point, believing everyone needs to hold something as brute. As a result, moral brute facts cannot be dismissed out of hand. However, the essay adds, binding moral obligations seem more than peculiar in a world of otherwise random particles moving through space. The tact of this answer as well as the first (and the essay as a whole) is to show that while objective moral claims and God can be doubted, alternative accounts of morality can’t make sense of what is left. Binding moral duties are a felt part of reality and to accept them is in the end to accept God.
William Lane Craig uses chapter eleven to give “The Argument from the Applicability of Mathematics.” The subject of his essay is largely the work of mathematician and physicist Eugene Wigner. In 1960, Wigner published a paper entitled “The Unreasonable Effectiveness of Mathematics in the Natural Sciences.” There he argued that complex mathematical concepts describe the world almost too well. His point is that many higher theories in math develop without any specific reference to the world and yet describe the world with astonishing detail and usefulness, especially in physics. Craig summarizes three of Winger’s examples: Newton’s second law of motion, matrices in quantum mechanics, and quantum electrodynamics. The intricacies of these equations aside, they illustrate a paradoxical correlation between abstraction and applicability in math: the more mathematically abstract the equation, seemingly the more applicable in physics. This is, of course, counterintuitive and why Wigner calls it “unreasonable.” Craig, for his part, considers whether current metaphysical accounts of mathematics can make sense of this obscure relationship. Today there are roughly two theories of what mathematical entities (e.g. numbers) are: either they are real (Realism) or not real (Anti-realism). On Realism, these entities exist eternally outside of time and space. On Anti-realism, they are only projections of the mind without any real existence beyond that. Both of these accounts on their own, Craig argues, cannot fully explain the applicability Wigner highlights. Whether numbers are real or not, there remains no explanation for why the world would reflect them or be amenable to their idea. At this, Craig proposes a theistic solution. God can make sense of the applicability of mathematics to the world insofar as God created the world according to a mathematical structure. Only this seems to be able to fully account for why mathematics—on Realism or Anti-realism—can explain the world.
The scope of these essays helps to articulate the exceptional breadth of Contemporary Argument in Natural Theology as a whole. The variety of arguments throughout the book provide a point of contact no matter the interest of the reader, and sprawling bibliographies at the end of each essay open up significant inroads to further study. In this way, the book is a great introduction to natural theology. This does not mean, however, that the essays are altogether easy. The analytic style can be tedious at times, and to understand more than the gist of the arguments will likely take a second reading. The most pressing issue, though, that the particular compilation produces is the question of whether or not every essay is working with the same idea of God. It can become unclear how the conception of God in one essay can fit within the framework of the next. This question may lie only on the surface, but seemed a significant one for this reader. Any substantive complaint beyond this comes down to symmetry. Together the essays read much more like a collection of works brought together in a book rather than for one. “The Argument from Beauty” is the most peculiar inclusion. Against the other seventeen essays that argue for God’s existence, it alone contends that beauty cannot provide an argument for God. Other quibbles and issues aside, Contemporary Arguments in Natural Theology is a worthwhile read for anybody interested in the topic.
Caleb Frens is a recent graduate from Westminster Seminary California (MDiv). He currently lives in Escondido with his wife Jennifer and their cat Malcom.