AO1 Ontological Argument

AO1: The Ontological argument’s status as an (a priori deductive) proof

Ontological arguments are a priori, meaning they are based purely on reason, not experience.
They begin with a definition of God:
The greatest conceivable being (Anselm).
A supremely perfect being (Descartes).
An unlimited being (Malcolm).
The argument then analyses what logically follows from this definition.
They are deductive, meaning that if the premises are true, the conclusion must be true.
The premises entail the conclusion, rather than merely supporting it.
Such arguments are often linked to rationalism, the view that reason alone can give knowledge of reality.
Though empiricists may accept them as a unique case where logic and fact converge.
Deductive arguments aim at certainty.
If successful, they show what must be true, not what is merely probable.
They are not defeasible like inductive arguments, since no new evidence can overturn a valid deduction.
So, they can only be challenged by rejecting the premises or denying that the conclusion follows from them.
They rely on analytic entailment, where what is contained in a concept determines what must be true of it.
The ontological argument claims that once the concept of God is understood, existence (or necessary existence) is entailed.
So, God’s non-existence would be a contradiction.
This would make “God exists” an analytic truth, which cannot be denied without contradiction.
Standard deduction works through categories.
E.g. all men are mortal, Socrates is a man, so Socrates is mortal.
But the ontological argument instead uses modal concepts like possibility and necessity.
A necessary being cannot fail to exist.
If such a being is possible, then it must exist in all possible worlds, including the actual world.
The claim is that reason can discover this with the same necessity.

AO1: Anselm’s ontological argument

Anselm’s ontological argument is a purely a priori analysis of the concept of God.
It is intended to be deductive, so the conclusion follows from the premises with necessity.
He uses the illustration of a painter who has an idea in their mind before painting it in reality.
This shows the distinction between something existing in the mind alone and existing both in the mind and in reality.
Anselm then refers to Psalm 14:1: “the fool says in his heart, ‘there is no God’.”
Even an atheist who denies God still has the idea of God in their mind.
In Proslogion 2, Anselm argues:
P1. God is the greatest conceivable being (by definition)
P2. It is greater to exist in reality than in the mind alone
P3. God exists in the mind
C1. Therefore, God exists in reality
The key claim is that God cannot exist only in the mind.
If God existed only in the mind, we could conceive of something greater, namely God existing in reality.
But this contradicts the definition of God as the greatest conceivable being.
So, the very concept of God implies real existence.
To deny God’s existence is effectively to say the greatest being is not the greatest, which is self-contradictory.
Malcolm and Hartshorne revived the argument in the 20th century, focusing on Proslogion 3.
Here Anselm develops the idea of necessary existence:
P1. A necessary being, whose non-existence is impossible, is greater than a contingent being
C1. Therefore, God necessarily exists
Malcolm interprets ‘greater’ in terms of limitation and dependence.
A contingent being depends on other things and can fail to exist.
But God, as unlimited, cannot depend on anything and so cannot fail to exist.
Hartshorne calls this “Anselm’s discovery”.
The key move is that if such a being is even possible, then it must exist necessarily.

AO1: Descartes’ Ontological argument

Descartes aimed to strengthen the ontological argument by grounding it in his rationalist epistemology.
Rationalism claims that we can gain absolutely certain knowledge of some truths a priori.
Anselm is often called the father of Scholasticism, which used Aristotle’s subject-predicate analysis.
Propositions combine subjects and predicates to assert something as true or false.
Descartes rejects this approach.
He argues that the foundation of knowledge is intuition.
Intuition is a direct intellectual awareness through clear and distinct perception, rather than step-by-step reasoning.
Intuition provides absolute certainty.
We can bring ideas before the mind and grasp truths about them through their clarity and distinctness.
He illustrates this with a triangle.
We intuitively know it is impossible to think of a triangle without three sides.
Similarly, we cannot think of a supremely perfect being without existence.
So, we grasp that existence belongs to God’s nature as a perfection.
Descartes claims this gives the same level of certainty as mathematical knowledge.
First, the idea of a supremely perfect being is found within us as clearly as the idea of any shape or number.
Second, we see just as clearly that existence belongs to God’s nature, as we do that a triangle has three sides.
Descartes also presents a short deductive version:
P1. The idea of a supremely perfect being contains all perfections.
P2. Existence is a perfection.
C3. Therefore, God exists.
The argument is deliberately brief, reflecting that knowledge of God is not mainly reached through reasoning.
For Descartes, we simply intuitively see that God exists, just as we see that a triangle has three sides.

AO1: Malcolm’s ontological argument

Norman Malcolm’s version of the ontological argument is a priori and deductive.
It proceeds through conceptual analysis rather than experience.
It uses modal logic, analysing necessity and possibility.
The aim is to show that if the concept of God is coherent, then God’s existence is necessary, not just possible.
Malcolm defines God as an unlimited being.
He prefers ‘unlimited’ to ‘greatest’ as it is less subjective and captures Anselm’s meaning.
A limited being depends on something else and can fail to exist.
An unlimited being has no dependencies and cannot fail to exist.
So, being unlimited implies necessary existence.
This definition is crucial.
God cannot have contingent existence, since that would involve dependence.
God also cannot have contingent non-existence, since contingency itself involves dependence.
So, only two options remain: God either exists necessarily or is impossible.
Malcolm formulates this into a modal argument:
P1. God’s existence is either necessary or impossible.
P2. If God exists, then God exists necessarily.
P3. If God does not exist, then God’s existence is impossible.
P4. God is not impossible (the concept is not self-contradictory).
C1. Therefore, God exists necessarily.
Following Leibniz, the argument depends on God being a coherent concept.
Malcolm makes this explicit in P4.
While there are debates about God’s coherence, Malcolm argues there is no clear proof of incoherence.
So, the only way to reject God’s existence is to claim the concept is incoherent.
This supports Anselm’s insight that if God is possible, then God must exist.

AO2 ontological content

AO2: Gaunilo’s ‘lost island’ objection

Gaunilo’s reductio ad absurdum argues that Anselm’s logic leads to absurd results.
If we apply the same reasoning to the greatest possible island, then following P2, it must exist.
This would apply to the greatest version of anything.
Reality would be absurdly ‘overloaded’ with the greatest conceivable versions of all things.
So, Gaunilo claims Anselm’s conclusion does not follow from the premises.
He is therefore denying the deductive validity of the ontological argument.

Counter

However, Anselm replies that the argument is only intended to work in the case of God.
Descartes develops this by arguing that God’s essence includes necessary existence, unlike contingent things.
An island is contingent by definition, as land enclosed by water, so it depends on water for its existence.
Like all empirical things, it can fail to exist.
So, no matter how great or perfect an island is, it remains contingent.
The argument therefore does not transfer to such cases.

Evaluation

This reply defeats Gaunilo because a priori reasoning can only establish the existence of a necessary being.
A priori arguments analyse definitions rather than appeal to experience.
Contingent beings have existence conditions separate from their definition, since they depend on external factors.
So their existence cannot be known a priori.
For example, I can know a priori that a perfect island requires water, but not whether that water exists.
So I cannot know a priori whether any contingent thing exists.
By contrast, a necessary being has no external conditions beyond its definition.
So, if the concept is coherent, existence follows.
There is therefore a relevant difference between God and contingent things which blocks Gaunilo’s analogy.
The objection fails because it tests the argument in a domain where its logic does not apply.

AO2: Gaunilo’s critique that God is beyond our understanding

Gaunilo objects to P3, the claim that God exists in our understanding.
He appeals to the classical idea that God is beyond human understanding.
If this is true, then Anselm cannot claim that God is present in the mind in a way that supports the argument.
So, he cannot move from God being conceived to God existing in reality.
The argument seems to assume a level of conceptual access to God that Gaunilo denies we have.

Counter

Anselm replies with an analogy: we cannot look directly at the sun, yet we can still see by its light.
Likewise, we may not understand what God is, but we can grasp that whatever God is, God is the greatest conceivable being.
We can recognise that in a hierarchy like greatness, there must be a highest point or intrinsic maximum.
That is all the argument requires.
Once we accept that it is greater to exist, the conclusion follows.

Evaluation

This objection fails because it misinterprets what Anselm means by God being “in the mind”.
Anselm uses in intellectu to mean “can be conceived”, not fully understood.
So, Gaunilo attacks a stronger claim than Anselm actually makes, committing a straw man.
The argument does not require full knowledge of God’s nature, only grasp of a formal concept of maximal greatness.
There is a clear distinction between knowing what God is and knowing that God is the greatest possible being.
Anselm only relies on the latter.
Furthermore, Gaunilo’s objection does not affect Anselm’s second form, which avoids this premise.
So even if the criticism worked, it would not undermine the strongest version of the argument.

AO2: Kant’s 2nd critique: existence is not a predicate

The ontological argument claims that denying God’s existence is incoherent, since God is defined as a maximally great being.
Kant argues this misunderstands existence by treating it as a predicate, a property of a thing.
He uses the example of 100 coins: there is no conceptual difference between 100 coins in reality and 100 coins in the mind.
If existence were a predicate, real coins would have an extra quality and be conceptually different.
But they are not.
So, existence is not a predicate.
This challenges the idea that existence makes something greater.

Counter:

However, Descartes does not rely on treating existence as a predicate, but on intuition.
We grasp that God is inseparable from existence, like a triangle is inseparable from three sides.
So Kant’s criticism misses Descartes’ argument.
Malcolm also defends Anselm.
Kant is right about contingent existence, since contingent things depend on something else.
But a necessary being contains the reason for its existence within itself.
So, necessary existence can be a defining quality in a way contingent existence is not.

Evaluation:

So, both Anselm and Descartes’ approaches succeed against Kant’s criticism.
Kant makes the same mistake as Gaunilo, thinking an argument for a necessary being could be undermined by showing it fails when applied to contingent things like coins.

AO2: Kant’s 1st critique: necessity doesn’t imply existence

Gaunilo criticised the move from necessity in thought to necessity in reality.
The Island (and Kant’s 100 coins) tries to show this mistake when applied to contingent things.
Kant better develops this point in his first critique, by applying it point to necessity itself.
A triangle necessarily has three sides.
But this only shows that if a triangle exists, then it must have three sides.
Likewise, God is defined as necessarily existing.
Yet this only shows that if God exists, then God exists necessarily.
So, necessary existence can be part of the concept of God without proving that God actually exists.
If God exists, denying God’s necessity is contradictory.
But if God does not exist, then neither does God’s necessity.

Counter:

Malcolm responds that Kant’s criticism is incoherent because a necessary being must exist.
If God is a necessary being, then God must exist.

Evaluation

Hick uses modern distinctions between types of necessity to challenge Malcolm.
Anselm and Malcolm argue that a maximally great or unlimited being cannot be contingent.
They then treat this as logical necessity.
Hick objects that this only shows God would be non-dependent and self-explaining (aseity).
This is ‘ontological necessity’, not logical necessity.
It describes how God would exist, not that God must exist.
So, God’s existence could still be a metaphysical ‘sheer fact’.
The ontological argument therefore cannot show that God’s non-existence is contradictory.
It only shows that if God exists, then God exists in a unique, non-contingent way.
So, Kant’s development of Gaunilo’s point is correct: necessity in a concept does not prove actual existence.