The Impossibility of God


Paul Copan

Article ID:



Jul 31, 2022


Jun 11, 2009

This review first appeared in the Christian Research Journal, volume 28, number 3 (2005). For further information or to subscribe to the Christian Research Journal go to:

Michael Martin is professor emeritus of philosophy at Boston University and author of books such as Atheism: A Philosophical Justification and Atheism, Morality, and Meaning. Ricki Monnier has a Ph.D. in mathematical logic and is director of the Disproof Atheism Society.

Their book The Impossibility of God is a hardly theism-friendly compilation of various “disproofs” for God’s existence. Its endorsement by the Midwest Book Review rather audaciously reads: “Every chapter in this book is logical, definitive, indisputable (except by unteachables) and provides complete proof of its conclusions.”

Despite this claim, the book contains a lot of disputable material. Many of its essays engage in question begging regarding God’s attributes and what should constitute a Being as great as God. Theists, however, can actually benefit from these critiques of formulations and discussions of God’s attributes without jettisoning the coherence of those attributes. Comprised of 33 essays written by a number of authors, The Impossibility of God gets fairly technical. I’ll summarize what I take to be some key issues raised by the book, focusing on only a few specific essays.

Definitions. Part one (“Definitional Disproofs of the Existence of God”) includes articles by J. N. Findlay, whose essays argue against the coherence of necessary existence—something he takes to be a contradiction in terms. Findlay embraces the view that existence can’t be included in the definition of something, which (unfortunately for the theist) is the very thing necessary in order for God to be “the adequate object of our religious attitudes” (p. 28). Theists, however, respond that the appropriation of modal logic and the language of possible worlds supports the idea of divine necessity and undermines the incoherence charge regarding the notion of logically necessary being. God’s necessity entails His existence in every possible world (“God exists” is true in every possible world); His nonexistence in any possible world is impossible.1

Douglas Walton’s essay, “Can an Ancient Argument of Carneades on Cardinal Virtues and Divine Attributes Be Used to Disprove the Existence of God?” uses an argument based on virtue to disprove God’s existence. The argument presented here is as follows: If a perfect, divine Being can be said to exist, this Being must be all-virtuous. One of those virtues must be courage. Courage necessarily involves the potential for being vexed as well as overcoming pains and dangers because “only for a being who can suffer or be destroyed are there pains and dangers” (37). If, however, God can be vexed and thus change for the worse, then God can’t be both virtuous and perfect.

This is not a decent “definitional disproof.” First, we know that some virtues emerge as a result of living in a fallen world; for example, the willingness to ask forgiveness when one has done wrong. This virtue, however, isn’t required of a supremely great God, who is without sin. Second, what is courage anyway? Aristotle defined it as the “golden mean” between foolhardiness and cowardice. This balancing act applies to human beings, who face danger, but not to God, who does not. Walton’s question-begging argument makes a category mistake, suggesting that God must somehow be subject to all the conditions that bring about virtues in humans (e.g., that God must face danger or destruction in order to be courageous).

Evil. In part two (“Deductive Evil Disproofs of the Existence of God”), there are two essays by the late atheist J.L.Mackie that each offer a “logical” argument against God’s existence based on evil. In “Evil and Omnipotence,” Mackie asserts, “God is omnipotent; God is wholly good; and yet evil exists. There seems to be some contradiction between these three propositions, so that if any two of them were true, the third would be false” (62). Mackie contends that the theist must adhere to all three propositions, yet cannot do so consistently.

The second essay, “The Problem of Evil” (from Mackie’s posthumously published Miracle of Theism), is similar. One problem with Mackie’s essay (83–86) is that it confuses a defense of the view that these three propositions are not contradictory with a justification or explanation for the last proposition, why God permits evil. One can, however, give a defense (show that these three propositions aren’t logically incompatible) without being able to explain why God permits certain evils.2 In fact, if God has morally sufficient reasons for permitting evil (even if we don’t know what they are), we could add that premise to the aforementioned three premises. Mackie’s deductive proof, then, fails. Philosopher Alvin Plantinga says of Miracle of Theism, “Mackie wavers between his earlier claim that the existence of God is straightforwardly inconsistent with that of evil and the claim that the existence of evil is powerful but not conclusive evidence against the existence of God.”3

Philosopher Peter van Inwagen writes that the thesis claiming that God and evil are contradictory (i.e., the deductive proof) is “no longer defended.”4 Even atheist William Rowe declares, “Some philosophers have contended that the existence of evil is logically inconsistent with the existence of the theistic God. No one, I think, has succeeded in establishing such an extravagant claim.”5

Against Plantinga’s “free will defense,” Mackie inquires about natural evils, not simply moral evils (84). The free will defense, however, is relevant even here. Peter van Inwagen effectively argues that human vulnerability to natural evils takes into account human freedom, serving as a reminder that all is not well with the world.6 Natural evils, like miracles, don’t compel or guarantee belief, but they have significant potential to awaken human beings to their vulnerability, finitude, and need for God.

What the essays in this section tend to assume is that things ought to be a certain way. If, however, atheism is true, why think this? Things just are the way they are. On the other hand, genuine evil—a departure from what ought to be—presupposes a kind of design or plan, which strongly suggests theism.

Doctrine. Part three (“Doctrinal Disproofs of the Existence of God”) has a variety of essays that attempt to show that God “does not and cannot exist” because certain attributes of God aren’t consistent with, say, Christian “doctrine, story, or teaching about God” (125). Richard R. La Croix’s essay, “The Paradox of Eden,” asserts that Adam and Eve either knew that obeying God is good and disobeying Him is evil (in which case Adam and Eve would have already possessed knowledge of good and evil and thus wouldn’t likely be tempted to eat the forbidden fruit because “they would have nothing to gain by disobeying God”) or, if they didn’t have this knowledge, then the test would be unfair since they “could not have known that it was wrong or evil to eat of the fruit” (in which case God acted unjustly for punishing them). Being just, therefore, “is not a necessary or essential property of God” (127–28, emphases in original).

La Croix, however, presents a false dilemma; for even if Adam and Eve didn’t know what evil was, they did know that it should be avoided and that they had an obligation to trust God’s goodness and character (which they had already experienced). Also, this command wasn’t a burden greater than they could responsibly bear.

An essay by Christine Overall deals with “Miracles as Evidence against the Existence of God.” Overall argues that miracles either violate natural law or are permanently inexplicable, both of which are inconsistent with the nature of God. Overall’s first premise wrongly assumes that natural laws are necessary (rather than contingent), but if science is to be open to studying inductively what takes place in the natural world, then it can’t rule out miracles in advance. That would violate an inductive approach to the available evidence. What if there are good theological or philosophical reasons for believing that a miracle (e.g., that the universe originated out of nothing a finite time ago) has taken place or supernatural causes are better than any natural causes at explaining the facts of a phenomenon (e.g., Jesus’ empty tomb)?

Overall’s second premise presupposes that only naturalistic explanations are acceptable, and all other types are invalid. What if, however, a self-revealing supernatural Being furnishes the needed historical and religious context for making sense of those miracles, which would make them far from permanently inexplicable?

Overall’s next essay, “Miracles and God,” assumes, for example, “the Law of Conservation of Energy” (i.e., energy can’t be created or destroyed). This is a naturalistic formulation of the law, however, which actually conflicts with big bang cosmology and the second law of thermodynamics. Energy began to be conserved once the universe began to exist. Physicist Paul Davies reminds us that, like it or not, we must admit that the universe’s energy was somehow simply “put in” at the creation as an initial condition,7 which strongly supports the doctrine of creation out of nothing.

Multiple Attributes. Part four (“Multiple Attributes Disproofs of the Existence of God”) covers attributes of God that are allegedly inconsistent with one another. Martin’s essay entitled “A Disproof of the God of the Common Man” asserts that God’s omniscience requires “all of men’s knowledge and more,” including knowledge of “lust and envy”; but this conflicts with “God’s moral goodness” (234). This argument, however, also engages in question begging. One can have profound knowledge of something without experiencing it. Nathaniel Hawthorne’s Scarlet Letter, for instance, describes postadultery emotions (e.g., guilt, self-deception) powerfully, compellingly, and grippingly, but this doesn’t mean that Hawthorne himself had to experience adultery to write about it effectively. How much more is this true of a God whose knowledge is complete and perfect? Further, God’s knowledge is not first-person (“I”) knowledge, save of Himself. God knows everything about George W. Bush, for example, but God, unlike Bush, doesn’t have the knowledge “I am President Bush.” Such knowledge isn’t only metaphysically impossible—despite Martin’s presumption of what omniscience should entail—but also delusional.

Single Attributes. Part five (“Single Attribute Disproofs”) argues that if God exists, then every one of His attributes must be self-consistent, but because particular attributes of God aren’t self-consistent, God does not and cannot exist. Gilbert Fulmer’s essay, “The Concept of the Supernatural,” for instance, asserts that God’s creating the universe takes for granted the “natural law” that whatever God wills to be created is created. The concept of supernatural agency “can provide no alternative explanation in terms of natural facts,” which is independent of God’s will; so there must be at least one fundamental fact that isn’t the result of any agent’s choice, which implies that “the universe itself must be ultimately impersonal” (329). This conclusion, however, doesn’t follow. Will isn’t the only attribute that characterizes personhood; reason8 and goodness9 are rooted in and bound up with God’s very nature and are important aspects of divine personhood, but these are attributes that are not willed. Furthermore, atheism must address certain problems of its own in this regard, such as how personhood could emerge from impersonal processes, reason from nonrational workings, and value from valueless events.

Another “disproof” concerns omnipotence. The “stone paradox” invariably emerges (mentioned in chapters 28 and 29 by J.L.Cowan): Can God make a stone so big that He can’t lift it? Whether God can or can’t make this stone, omnipotence is an incoherent concept. The theist, however, asserts that the challenge itself is incoherent and nonsensical, since it involves statements or propositions that are not only about “things or tasks” (340) but about the very nature of God, which are by definition impossible: by definition “God-defying rocks” can’t exist, just as by definition God can’t make Himself nonexistent. To say that God bears these alleged “inabilities” is no more a slight on God’s power than to say that a superior military commander can’t lose in battle.

Cowan raises the question of God’s omnipotence and human freedom (as does James Rachels in chapter 5, where he claims that the believer must both employ moral autonomy and forsake it in worshiping God): Doesn’t God’s omnipotence necessarily block moral autonomy and human freedom? Not at all. Logically, God can’t make humans do something freely. God gives humans freedom to live in relationship with Him or to reject Him and His initiating (prevenient) grace. Freely choosing either separation from God or bliss with Him means having one’s way forever. Combined with God’s knowledge of all possible worlds and of future free human choices, God’s omnipotence operates in conjunction with, rather than in opposition to, human choices to accomplish His purposes in this actualized world.

Against the claims of such essays, theists would argue that omnipotence doesn’t involve God’s being able to do what is actually impossible, just as omniscience doesn’t entail God’s having the knowledge that He is President Bush. Omnipotence involves God’s having maximally perfect power, which is bound up with His goodness, justice, compassion, and other attributes—the balance of which makes God supremely great.10

In studying God’s attributes, we should not tear omnipotence or omniscience from moral goodness or supreme wisdom as these critical essays tend to do. God’s omnipotence isn’t brute force; His omniscience isn’t mere information storage—none of His attributes are detached from His holiness.

Recommended Reading. Because this critique is necessarily short, I would recommend the following for further reading on the divine attributes: Charles Taliaferro, Contemporary Philosophy of Religion (Blackwell), William Lane Craig and J.P.Moreland, Philosophical Foundations for a Christian Worldview (InterVarsity Press); Thomas Morris, Our Idea of God (InterVarsity Press); William Lane Craig, Philosophy of Religion: A Reader and Guide (Rutgers University Press); and the journals Philosophia Christi and Faith and Philosophy. These works underscore the fact that God isn’t only possible, but necessary.

— reviewed by Paul Copan


1. See Stephen T. Davis’s discussion of Kant in “The Ontological Argument” in The Rationality of Theism, eds. Paul Copan and Paul K. Moser (London: Routledge, 2003).

2. See Alvin Plantinga’s critique of Mackie’s book—and more specifically the argument from evil—in “Is Theism Really a Miracle?” Faith and Philosophy 3, 2 (April 1986): 109–34.

3. Alvin Plantinga, “Epistemic Probability and Evil,” in The Evidential Argument from Evil, ed. Daniel Howard-Snyder (Indianapolis: Indiana University Press, 1996), 93n3.

4. Peter van Inwagen, “The Problem of Evil, the Problem of Air, and the Problem of Silence,” in The Evidential Argument from Evil, 150.

5. William L. Rowe, “The Problem of Evil and Some Varieties of Atheism,” American Philosophical Quarterly 16 (October 1979): 41n1.

6. Peter van Inwagen, “The Magnitude, Duration, and Distribution of Evil,” God, Knowledge and Mystery: Essays in Philosophical Theology (Ithaca, NY: Cornell University Press, 1995).

7. P. C. W. Davies, The Physics of Time Asymmetry (London: Surrey University Press, 1974), 104.

8. Victor Reppert, C. S. Lewis’s Dangerous Idea (Downers Grove, IL: InterVarsity Press, 2003).

9. John Rist, Real Ethics (Cambridge: Cambridge University Press, 2003), 27–60.

10. Charles Taliaferro, Contemporary Philosophy of Religion (Cambridge: Blackwell, 1998), 77. Note Taliaferro’s critique of Martin’s analysis of omnipotence (80–81).

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