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What does heaven look like? Does the heaven imagined by Fred “God hates fags” Phelps match that of Mother Teresa, who said, “The world gains much from [the poor’s] suffering”? Do these heavens match that of Maximilian Kolbe, the friar who volunteered to die in the place of a stranger in Auschwitz? These are three Christians with three possibly incompatible views of heaven.

Suppose the properties of Paradise are what we imagine them to be. The British comedy Red Dwarf explored this idea of the perfect life in one episode. In “Better than Life,” the three characters enter a total immersion game that’s better than life. They get whatever they want—food, cars, cash, girlfriends, power. Things go wrong when one of the characters can’t accept good things happening to him and corrects the balance by imagining his father’s disapproval, then being saddled with a nagging wife and seven children, and finally that all of the characters are buried up to their necks with jam on their faces, about to be eaten by ants.

This was just a television show, but if you reject the idea of imagining into existence the properties of a perfect life, you won’t care for this Christian apologetic argument.

Ontological Argument

Here’s the original argument as formulated by Anselm of Canterbury a thousand years ago. First define “God” as the greatest possible being that we can imagine. Next, consider existence only in someone’s mind versus existence in reality—the latter is obviously greater. Finally, since “God” must be the greatest possible being, he must exist in reality. If he didn’t, he wouldn’t meet the definition of the greatest possible being.

But this is crazy talk. How is this not wishing something into existence as with the Red Dwarf episode? If we can simply think God into existence, can we think other perfect things into existence as well?

This is a little like Zeno’s paradox. The conclusions of neither Zeno’s paradox nor the Ontological Argument seem to follow, and yet the error isn’t obvious.

Rebuttals to the Ontological Argument

But perhaps our intuition fails us here. Let’s be more rigorous and explore some rebuttals.

1. Does the thing exist or not? The most obvious flaw is that the first step defines an imaginary being—God is the greatest possible being that we can imagine. But in step three, we are now talking about beings that exist. The definition of “God” from the first step no longer applies. We’re switching definitions mid-argument.

2. “Greatest” is subjective. This was the lesson from the Better Than Life game. Consider a few examples: I like sugar in my tea, you like your tea straight, and the Mormon either has iced tea or avoids tea altogether. “The greatest cup/glass of tea” is not definable.

Or religion: Muslims say that their religion is best because it’s a monotheism. Christians say that their Trinity is better. Which is greater?

Or warfare: was the English victory at Agincourt or the Greek holding action at Thermopylae greater? Was Hannibal’s generalship greater than that of Julius Caesar? Chinese strategist Sun Tzu said that the greatest battle is the one that was avoided. So then is the greatest superhero the one who kicks the most butt or the one whose diplomacy avoids the most butt kicking?

Is the greater god the omnipotent one, or is he the one limited in power but who overcomes his limitations and nevertheless gets things done by cooperation? The Buddhist has yet another approach and will argue that the greatest being has “completely purified his mind of the three poisons of desire, aversion, and ignorance.”

One Christian imagines Buddy Christ and another a severe and unfriendly Yahweh—which one is better? Joel Grus said, “Yahweh doesn’t have a rocket-powered jetpack, and a deity with a rocket-powered jetpack is easily ‘greater’ than one who doesn’t have it.” “Greatest being” is like “the highest integer”—you can always go a little higher.

The first point in the argument—“God is the greatest being that we can imagine”—is not well defined, just like there is no “greatest presidential candidate.” These are subjective categories.

3. What’s better—the God of the OT existing or his not existing? Obviously the latter! We can puzzle about the existence of the greatest possible being, but the reprehensible Yahweh of the Old Testament clearly isn’t it. (More here, here, here, here, here, here, here, and here.)

At best, the Ontological Argument is yet another deist argument; that is, it argues for an unspecified deity rather than the god of the Bible. If it were convincing, the Christian would still need to argue for which god.

4. The greatest possible being can’t create. The greatest possible being is perfectly satisfied and has no needs. No needs means no motivation to change or create, so it can’t be the creator of our universe.

5. The Ontological Argument invites its negative version. If we’re just imagining things into existence, other things will come through that door.

Define “God” as the worst possible being that we can imagine. Next, consider existence only in someone’s mind versus existence in reality—it would obviously be worse if this being actually existed. Finally, since “God” must be the worst possible being, he must exist in reality.

6. Questions about existence. Philosophers for the last millennium have wrestled with the Ontological Argument with no consensus. David Hume observed that to think of a unicorn (for example) is to think of it existing. Adding a second step after we’ve thought of a unicorn, “Okay, now think of it existing,” is meaningless. The same is true of God—the idea of God is the idea of God existing, and the argument no longer works.

Immanuel Kant argued that existence is not just another property like “blue” or “has four legs” that you can imagine (or not) about something. Theologian J.W. Montgomery agreed, “If one removes all the genuine properties from something, one does not find that existence remains; existence is the name we give to something that has properties” (Tractatus Logico-Theologicus, 119).

7. The Ontological Argument creates a moral conundrum. Here’s a nice refutation from commenter Greg G.

  1. The greatest possible being would also be a morally perfect being.
  2. A morally perfect being would prevent all unnecessary suffering.
  3. For suffering to be necessary, it must achieve some purpose, and this purpose must also be logically possible to achieve.
  4. The morally perfect being (being the greatest possible being) would also be omnipotent. An omnipotent being is able to do every logically possible thing, so it could achieve every purpose alluded to in #3.
  5. But if the morally perfect being could achieve every purpose by itself, achieving it through suffering is unnecessary.
  6. That means that all suffering is unnecessary, which means it is impossible for a being that is both omnipotent and morally perfect to exist in this world.
  7. Therefore, the greatest possible being can’t exist. QED.


Imagine that you’re balancing your checkbook. You’re tallying up a list of figures and then stare at your calculator. Wow, you actually have a million dollars more than you thought—happy day!

When most of us reach a conclusion that seems to be crazy, we suspect that there’s something wrong with our analysis. Wishing God into existence is one of those too-good-to-be-true arguments that demands skepticism.

Let me admit that this post isn’t thorough and can only explore the ideas behind the Ontological Argument. Eager Christian apologists through the centuries have proposed many variations, taking a discarded version and giving it low-profile tires, spinning rims, and a new paint job. If you slap down one argument, they’re sure to demand that you evaluate all the others.

Are any of these variants valid? Do they prove God’s existence? I doubt it, but think of what this says about the arguments supporting Christianity. Must you really resort to such esoteric and impenetrable arguments to show the existence of a caring god who desperately wants you to know about him?

The Ontological Argument is effective because it violates Hoare’s Dictum. It’s complicated enough that there are no obvious errors. That’s its strength—not that it’s correct but that it’s confusing.

“That than which nothing greater can be conceived”
is most likely an empty set.
Draw conclusions accordingly.
— Joel Grus


(This is an update of a post that originally appeared 9/24/14.)

Image via Wikimedia, CC license


CROSS EXAMINED In his first career, Bob Seidensticker designed digital hardware and was a contributor to 14 software patents. Since then, he has explored the debate between Christianity and atheism for...