The Ontological argument: Edexcel B grade notes

Edexcel
Philosophy

Anselm’s ontological argument is a purely a priori argument based on the concept of God.
It is deductive, aiming to prove God exists with necessity.
Anselm uses the example of a painter who first has an idea in their mind before creating it in reality.
This shows the difference between existing in the mind and existing in reality.
He refers to Psalm 14:1, where the atheist denies God.
Even the atheist has an idea of God in their mind.
In Proslogion 2, Anselm argues:
P1. God is the greatest conceivable being.
P2. It is greater to exist in reality than only in the mind.
P3. God exists in the mind.
C1. Therefore, God exists in reality.
If God existed only in the mind, we could imagine something greater: God existing in reality.
So, God must exist in reality.
In Proslogion 3, Anselm argues that a necessary being is greater than a contingent being.
A necessary being cannot fail to exist.
So, God, as the greatest being, must exist necessarily.

Ontological arguments are a priori, meaning they are based on reason alone, not experience.
They begin with a definition of God, such as the greatest conceivable being, a supremely perfect being, or an unlimited being.
The argument then examines what follows from this definition.
They are deductive, so if the premises are true, the conclusion must be true.
The conclusion is logically entailed, not just supported.
They are often linked to rationalism, though some empiricists accept them as a special case.
Deductive arguments aim at certainty.
If successful, they show what must be true.
They cannot be overturned by new evidence.
So, they can only be challenged by rejecting the premises or the logic.
They rely on analytic entailment, where truths follow from the meaning of a concept.
The ontological argument claims that existence is contained within the concept of God.
So, denying God’s existence would be a contradiction.
Unlike standard deductions, this argument uses modal ideas like necessity and possibility.
A necessary being cannot fail to exist.
If such a being is possible, then it must exist in reality.
So, reason alone is claimed to establish God’s existence.

Gaunilo’s ‘lost island’ objection
Weakness: The ontological argument appears to generate absurd conclusions when its logic is applied to contingent objects like a perfect island.
Strength: The argument distinguishes necessary from contingent beings and limits its applicability to necessary a being whose existence is contained within its definition.
Gaunilo: God beyond understanding
Weakness: The claim that God exists in the understanding is challenged by the view that God is beyond human comprehension.
Strength: The argument only requires understanding that whatever God is, God is the greatest conceivable being, rather than fully understanding God’s nature.
Kant: existence is not a predicate
Weakness: The argument is criticised for treating existence as a predicate, even though existence does not add anything to the concept of a being.
Strength: The argument specifically draws on the concept of a necessary being, a unique case where necessary existence could be defended as a predicate.
Kant: necessity doesn’t imply existence
Weakness: Defining God as a necessary being does not establish actual existence, since necessity may only describe how God would exist if God exists.
Strength: The argument is grounded in the powerful reasoning that God is a necessary being which therefore must exist, as its non-existence would contradict its nature.

Gaunilo argues that Anselm’s logic leads to absurd results.
If we apply it to the greatest possible island, then it must exist.
This would apply to anything, meaning reality would be ‘overloaded’ with perfect versions of everything.
So, Gaunilo claims the conclusion does not follow from the premises.
He is rejecting the argument’s deductive validity.

Counter

Evaluation

This reply succeeds because a priori reasoning only works for necessary beings.
It analyses definitions rather than checking reality.
Contingent things depend on external conditions, so their existence cannot be known a priori.
For example, I can know a perfect island needs water, but not whether that water exists.
So I cannot prove a contingent thing exists through reason alone.
But a necessary being has no external conditions.
So, if its concept is coherent, it must exist.
There is a clear difference between God and islands.
Gaunilo’s objection fails because it applies the argument where it does not belong.

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.

Gaunilo argued that necessity in thought does not give necessity in reality.
Kant develops this by focusing on necessity itself.
A triangle must have three sides, but only if it exists.
In the same way, saying God necessarily exists only shows that if God exists, then God exists necessarily.
So, necessity can be part of the concept without proving real existence.
If God exists, denying necessity is contradictory.
But if God does not exist, then necessity does not apply.

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 argues that Malcolm confuses different types of necessity.
Calling God non-contingent only means God would be self-explaining and non-dependent (aseity).
This is not logical necessity.
It does not mean God must exist, only how God would exist if real.
The argument fails to show that God’s non-existence is contradictory.
It only shows that if God exists, God exists in a special way.
So, Kant’s development of Gaunilo’s point is correct: necessity in a concept does not prove actual existence.