Eduqas
Philosophy

This page contains A*/A grade level summary revision notes for the Ontological argument topic.

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For AO1 you need to know:

Deductive proofs & ‘a priori’
Anselm’s 1st argument in Proslogion 2
Anselm’s 2nd argument in Proslogion 3
Descartes’ ontological argument
Malcolm’s ontological argument
Gaunilo’s objection of the perfect island
Kant’s objection that existence is not a predicate

For AO2 you need to be able to debate:

The extent to which ‘a priori’ arguments for God are persuasive
The extent to which different religious views on the nature of God impact on arguments for the existence of God.
The effectiveness of the ontological argument for God
Whether the ontological argument is more persuasive than the cosmological/teleological arguments
The effectiveness of the challenges to the ontological argument
The extent to which objections to the ontological argument are persuasive

AO1 Ontological Argument

AO1: Anselm’s ontological argument

Anselm’s ontological argument is a priori; based purely on a logical analysis of the concept of God, with no appeal to experience.
Deductive, if the premises are true, the conclusion must be true.
Anselm uses the illustration of a painter who has an idea of what they will paint in their mind before painting it in reality.
This illustrates the distinction between our idea of something existing in the mind alone, verses existing both in the mind and in reality.
Anselm then points to Psalm 14:1 “the fool says in his heart, ‘there is no God’.”
An atheist says they do not believe in God, but they at least have an 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 the mind alone
P3. God exists in the mind
C1. Therefore, God exists in reality
The force of Anselm’s argument is that God cannot be an idea that exists in the mind alone (as an Atheist thinks).
That would be incoherent, since then we could conceive of something greater, i.e., God also existing in reality.
Yet, God is the greatest being, so conceiving of anything greater is incoherent.
So, our idea of God must therefore be of a being that exists in reality.
To say that God does not exist in reality is effectively to say that the greatest being is not the greatest being. It is self-contradictory.
Malcolm and Hartshorne were responsible for renewing interest in the Ontological argument in the 20th century. They point to Proslogion chapter 3 as containing the strongest presentation of the argument.
There, Anselm argues:
P1. A necessary being whose nonexistence is impossible is greater than a contingent being whose nonexistence is possible.
C1. Therefore, God (as the greatest conceivable being), necessarily exists.
Malcolm interprets Anselm’s term ‘greater’ as referring to degrees of limitation, such as dependence on other things for existence.
God must be unlimited, without any of the contingencies of ordinary beings which make their non-existence possible.
So, a being greater than which none may be conceived is one whose nonexistence is impossible.
Hartshorne calls this insight “Anselm’s discovery”.
In his replies to critics, Anselm concludes that if such a being is logically possible, then it must exist.

AO1: Descartes’ Ontological argument

Descartes aimed to strengthen the ontological argument through founding it on 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, a theological movement influenced by Aristotle’s approach to argumentation. At its core is subject-predicate analysis. Propositions are combinations of subjects and predicates which assert something as true or false.
Descartes rejected scholasticism. He instead argued that the foundation of knowledge was intuition. Intuition operates through direct intellectual awareness, not the indirect analysis of linguistic representation employed by logical terms.
Intuition provides absolute certainty. We can bring ideas before our mind and apprehend truths about them due to the psychological character in which they strike us.
E.g., we intuitively know that it is impossible to bring a triangle before our mind without it having three sides. Similarly, we intuitively know it impossible to think of a supremely perfect being separated from existence. We thus rationally appreciate that God contains the perfection of existence.
“the idea of God, or a supremely perfect being, is one that I find within me just as surely as the idea of any shape or number. And my understanding that it belongs to his nature that he always exists is no less clear and distinct than is the case when I prove of any shape or number that some property belongs to its nature” – Descartes
Descartes did put it into the form of a deductive argument:
P1 – I have an idea of a supremely perfect being which contains all perfections
P2 – Existence is a perfection
C3 – God exists
The argument is deliberately short, suggestive of Descartes’ view that God’s existence can be known intuitively.
For Descartes, knowing God’s existence isn’t a matter of reasoning from premises to a conclusion.
We simply intuitively know that God exists, just as we know a triangle has three sides.

AO1: Malcolm’s ontological argument

Norman Malcolm created his own version of the ontological argument, referring to God as an unlimited being.
Malcolm thought ‘unlimited’ was a better term than ‘greatest’ because it captures what Anselm meant by the greatest being. A limited being could not exist, due to its limitations. An unlimited being cannot not exist because it contains the impossibility of non-existence. ‘Unlimited’ sounds less subjective than ‘greatest’.
Malcolm uses modal logic, which involves analysis of the logical consequences of necessity and possibility. It typically involves arguing from what is possible to what is actual.
P1. God either exists or does not exist.
P2. If God exists, God cannot go out of existence as that would require dependence on something else. So, if God exists, God exists necessarily
P3. If God does not exist, God cannot come into existence as that would make God dependent on whatever brought God into existence (and thus limited). So, if God does not exist, God’s existence is impossible.
C1. So, God’s existence is either necessary or impossible
P4. The concept of God is not self-contradictory (like a four-sided triangle), therefore God’s existence is not impossible.
C2. Therefore, God exists necessarily.
No form of contingency can apply to an unlimited being. God could not contingently exist, nor contingently not exist. The only remaining possibilities are either that God is incoherent or that God exists necessarily.
Since Leibniz, proponents of the ontological argument have accepted that it depends on God being a logically coherent concept. Malcolm makes that a clear premise of the argument in P4.
There are lots of debates about whether God is coherent, but Malcom thinks there haven’t been any clear proofs of incoherence.
Malcolm concludes the only way one could reject God’s existence is to deny that God is coherent.
If the idea of God makes sense at all, then God must exist.

AO2 ontological content

AO2: Gaunilo’s ‘lost island’ objection

Gaunilo attempts to show Anselm’s logic is absurd by applying it to another case which yields an absurd result.
Imagine the greatest possible island. If it’s greater to exist then this island must exist.
This would work for the greatest possible version of anything.
Anselm’s logic implies reality would be overloaded with the greatest conceivable version of every possible thing, which seems absurd.
Gaunilo is attempting to deny that the ontological argument’s conclusion follows from the premises. So he is denying that it really is a valid deductive argument.

Counter

Anselm replied that his argument is only intended to work in the case of God.
An island by definition is contingent. It is land enclosed by water, so it depends on water for its existence.
Therefore, no matter how great or perfect an island is, it will still be contingent.
This is true of all things in the world.
So, there’s a relevant difference between God and contingent things like Islands which explains why the logic works exclusively for God.

Evaluation

Anselm’s reply defeats Gaunilo because a priori reasoning can only demonstrate existence in the case of a necessary being.
A priori reasoning involves the analysis of the definition of concepts.
The definition of contingent things is that their existence depends on something else.
Contingent things can only exist if what they depend on exists (at some prior point).
Whether what they depend on exist(s/ed) is not part of their definition.
So, a priori reasoning cannot determine the existence of contingent things.
E.g., I can tell a perfect island depends on water to exist, but I can’t tell a priori whether that water does exist. So I can’t know a priori whether a perfect island, or any other contingent thing, exists.
For necessary beings, by contrast, there is no non-definitional existence requirement.
The argument therefore works exclusively in the case of the greatest conceivable being.
Its logic cannot be tested where it doesn’t belong, through reference to contingent beings.

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

Gaunilo objects to P3, the claim that God is in our mind/understanding.
He invokes the classical notion that God is beyond our understanding.
In that case, Anselm can’t go on to conclude that God being the greatest being requires that he is not just in our understanding, but also in reality.

Response:

Anselm replies with an analogy: just because we cannot look directly at the sun, doesn’t mean we can’t see by sunlight.
Similarly, just because we can’t understand what God is, doesn’t mean we can’t understand that whatever God is, God is the greatest conceivable being.
We can understand that in a hierarchy, like greatness, there must be a highest point or ‘intrinsic maximum’, to use Plantinga’s modern term.
That’s all we need to understand for Anselm’s argument to work.
When we combine that with the premises that it is greater to exist, we can then deduce the conclusion that the greatest conceivable being exists.
We don’t need to understand what a maximally great being actually is, only that whatever it is, it is the pinnacle of the greatness hierarchy.

Evaluation:

Firstly, Gaunilo’s critique doesn’t work against Anselm’s 2nd form of his argument, which doesn’t rely on a premise about God existing in the mind.
Gaunilo misunderstands P3 and commits a straw man fallacy, attacking a claim Anselm didn’t make.
In P3, Anselm uses ‘in intellectu’, meaning ‘can be conceived or thought about’, not ‘fully understood’.
Anselm didn’t mean God is in the mind in the sense of us having full knowledge of God’s substantive nature, just that we understand something proper to the form of God, that God is maximally great.

AO2: Kant: existence is not a predicate

The ontological argument claims that denying God’s existence is an incoherent denial of what God is (a maximally great/perfect being).
Kant responds that this misunderstands what existence is by treating it like a predicate (a description of what a thing is).
He illustrates that there’s no conceptual difference between 100 coins in reality versus only in the mind.
If existence were a predicate, it would describe a quality of the real coins.
They would then be conceptually different to the mental coins.
But, they are not. 100 coins is just 100 coins, defined by the predicates of 100, round, shiny, etc.
So, existence is not a predicate.
This attacks the premise that existing is greater or more perfect.
If existence is not part of what God is, we can deny God’s existence without contradicting what God is.

Response:

Descartes’ epistemology doesn’t rely on Anselmian scholastic attribution of predicates to subjects, but on intuition.
We rationally appreciate that God is inseparable from existence, just as a triangle is inseparable from three sides.
So Kant’s criticism fails against Descartes.
Malcolm also defends Anselm.
Kant is correct, but only about contingent existence.
The reason for the existence of a contingent thing is dependence on something else, so is external and not a defining part of it.
However a necessary being contains the reason for its existence within itself.
So, necessary existence is a defining quality of a thing, in a way contingent existence is not.
So necessary existence is a predicate.

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: necessity doesn’t imply existence

Gaunilo’s island illustrated the distinction between necessity in mental judgement versus necessity in reality.
The Island (and 100 coins) seemed to make the mistake of testing Anselm’s logic on contingent things.
Kant’s first critique properly focuses on necessity:
A triangle necessarily has three sides.
This proves that if a triangle exists, then it necessarily has three sides.
God is a being which necessarily has existence.
However, this only shows that if God exists, then God exists with necessity.
If God exists, it’s contradictory to deny God’s necessity.
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 we accept that God is necessary, we cannot deny that God exists.

Evaluation

However Hick successfully defends Kant’s style of objection.
To show that God’s non-existence is contradictory, the ontological argument needs to show God is logically necessary.
The justification provided is that a maximally great or unlimited being cannot have the contingent dependencies of ordinary beings.
However, non-contingency does not equate to logical necessity.
It only implies something metaphysical about God’s mode of being: eternal, non-dependent and self-explaining being (aseity). Hick calls this ‘ontological’ necessity.
A non-contingent being could fail to exist, because its existence would be a metaphysical fact (what Hick calls a ‘sheer fact’), not a logical requirement.
So, the ontological argument cannot establish the impossibility of God’s non-existence (i.e., that God has logical necessity).
It at most proves that if God exists, then God exists in a metaphysically special way, with ontological necessity.
Gaunilo’s point that conceptual necessity doesn’t entail real necessary existence was right, but needed these distinctions between types of necessity to make clear why.