The Rejection of Pascal's Wager
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The Ontological Argument

The first argument we will look at is the so-called Ontological Argument. [a] The argument was first introduced by St. Anselm (1033-1109), Archbishop of Canterbury, in his book Proslogium. Anselm was one of the first Christian theologian who defended his faith on reasoning rather than by an appeal to Scripture or tradition. [1]

The Ontological Argument

In the Proslogium, Anselm began his argument by quoting a passage from Psalms (14:1) which says: "The fool says in his heart, 'There is no God.'" Now God, according to Anselm, is "that than which nothing greater can be conceived." So when an atheist, that is, the fool, says that "god does not exist", he means that "that than which nothing greater can be conceived" exists only in the mind but not in reality. But, Anselm added, for a thing to exists in reality is surely greater than that which exists only in the mind. Now obviously, "that than which nothing greater can be conceived" must exist in reality for that definition to hold. [2] As Anselm himself puts it:

If that than which nothing greater can be conceived, exists in the understanding alone, the very being, than which nothing greater can be conceived, is one than which a greater can be conceived. Obviously this is impossible. Hence there is no doubt that there exists a being, than which nothing greater can be conceived, and it exists both in the understanding and in reality. [3]

According to Anselm's Ontological Argument, one cannot deny the existence of God without involving oneself in a contradiction. Anselm's God, by definition, exists!

The Ontological Argument gives one a feeling of unease; a feeling akin to seeing a magician pulling a rabbit out of a hat; there must be a trick somewhere! In fact, there are so many things wrong with Anselm's argument that almost every generation of philosophers has succeeded in poking holes in it!

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Critique of the Ontological Argument

1. The Form of the Argument is Suspect

The first critique actually came from a contemporary of Anselm. It was a French monk, Gaunilon, who wrote a reply to Anselm entitled On Behalf of the Fool. [4] Gaunilon's critique was aimed mainly at the form of the Ontological Argument.

To this line of reasoning, he applied Anselm's logic on a "perfect" island. Suppose that beyond the boundary of man's known world (remember this was the eleventh century), there is an island. Suppose that this island is perfect and greater than all islands: an island than which none greater can be conceived. To use Anselm's logic, if this island exists only in the imagination it would be less great than that which exists in reality. Hence the "island than which none greater can be conceived" must exist in reality! [5] In a way, Gaunilon has shown that not only can the Anselmian magician pull a rabbit out of a hat, he can pull anything he wants, including the proverbial kitchen sink!

Used on an island, or any other thing, this form of argument is surely absurd. As Gaunilon wrote:

If a man should try to prove to me by such reasoning that this island truly exists...either I should believe he was jesting, or I know not which I ought to regard as the greater fool: myself, supposing I should allow this proof; or him, if he should suppose that he had established with any certainty the existence of this island. [6]

Anselm's reply was, in my opinion, weak and unconvincing. He asserted that an island is not something which can not be thought of as not existing. [7] In short, the Ontological Argument is applicable only to God! [8] This reply is unsatisfactory because it disallows any analogy by which the form of the argument can be tested.

Gaunilon's argument, in fact, exposes a basic flaw in the Ontological Argument. If the "most perfect island" is an object, according to Anselm, that can be imagined to be non-existent, then it follows that existence itself could not be an added perfection. Hence it makes no difference to the idea of perfection, whether the object (be it island or God) exists in reality or only in the mind. [9]

Existence is Not a Predicate

In the eighteenth century, the German philosopher, Immanuel Kant (1724-1804) further refined Gaunilon's objections to the Ontological Argument.

Existence, says Kant, is not a predicate. By that, he meant that saying that a being or creature or thing exists we are not adding anything to the properties that define it. [b] Take, as an example, the mythical centaur. We can define this by listing its properties; namely that it is a creature with a head, body and hands of a man attached to the body and legs of a horse. If we add to that statement that centaurs exists, we are not adding anything to the property of the creature. [10]

The concept is not changed whether one is merely thinking about it or one is thinking of it as existing. Hence, as applied to God, one's idea of a perfect being is not changed whether one is only thinking about it or thinking about it as existing. [11]

Now if supporters of the Ontological Argument assert that with God, existence is a part of the definition of the divine being such that it cannot be denied without self-contradiction, they face another difficulty. In this way they have made the statement "God exists" an analytic statement. Analytic statements are statements that simply restate the property that is already defined in the object; i.e. they tell us nothing new. All analytic statements are tautological. An example of an analytic statement would be "all husbands are male spouses". Nothing new is being conveyed by that statement for part of the definition of husband is "male spouse". Its the same with a triangle; for example "a triangle is a plan figure having three angles." Now Kant says:

to posit a triangle, and yet to reject its three angles, is self contradictory; but there is no self-contradiction in rejecting the triangle together with its three angles. The same holds true of the concept of an absolutely necessary being. If its existence is rejected, we reject the thing itself with all its predicates; and no question of a contradiction can then arise. [12]

What Kant is saying is that the truth of any analytic statement is purely conditional. It does not and cannot prove the existence of whatever regarding what it is talking about. So the assertion "God exists" simply means "If God exists (the condition), then he exists (part of the definition)". To sum up his argument (given in The Critique of Pure Reason [1781]), Kant concluded:

To attempt to extract from a purely arbitrary idea, the existence of an object corresponding to it, is a quite unnatural procedure and a mere innovation of scholastic subtlety. [13]


Our conclusions on the Ontological Argument are:
  • The form of the argument is suspect as it cannot be appled on anything except God.
  • If the argument refers to the actual world, it is fallacious because existence is not a predicate, that is existence is not an added perfection.
  • If necessary existence is defined into God, the arguments becomes tautological and has no connection with reality.
Any which way you look at it, the Ontological Argument fails to prove the existence of the God.

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a.Ontology is the study of real existence.
b.This is actually very similar to the exchange between Gaunilon and Anselm. When Gaunilon brought up the example of the perfect island he was showing that existence is not an "added perfection", i.e. not a predicate. And Anselm, unwittingly agreed with this when he said that a "perfect island" can be conceived to be not existing. It is quite curious that this basic similarity between Kant's argument and Gaunilon's has not, to my knowledge, been admitted by philosophers.


1.Livingstone, Dictionary of the Christian Church: p24
2.Miller, God and Reason: p26
3.Alston & Brandt, The Problems of Philosophy: p22
4.Miller, God and Reason: p29
5.Popkin & Stroll, Philosophy: Made Simple: p157
6.Jones, A History of Western Philosophy: II The Medieval Mind: p204
7.James Ross, Introduction to the Philosophy of Religion, Macmillan, Toronto 1969: p24-25
8.Popkin & Stroll, Philosophy: Made Simple: p157
9.Jones, A History of Western Philosophy: II The Medieval Mind: p204-205
10.Ayer, The Central Questions of Philosophy: p214
11.Popkin & Stroll, Philosophy: Made Simple: p158
12.Miller, God and Reason: p33
13.Ibid: p34

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