The Ontological argument A* grade notes

Eduqas
Philosophy

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

Ontological arguments are a priori, meaning they are based purely on reason, not the application of reason to 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 involves a purely conceptual analysis of the logical implications of this definition.
It proceeds by claiming that if God not existing would contradict the definition of God established.
Since non-existence would be less great, less perfect, or imply a limitation.
The argument is designed so that if one accepts the definition of God, one then has to accept that God is proven to exist.
The argument is deductive, meaning that if the premises are true, the conclusion must be true.
A priori deductive arguments are often associated with rationalism, the view that substantive knowledge of reality can be gained through reason alone.
Though, they can also be accepted by empiricists, who may regard God as a unique case where logical truth and factual truth converge.
In deductive proofs, the truth of the premises logically entails the truth of the conclusion.
They do not merely support its probability, like Inductive proofs.
If successful, they demonstrate what must be true, not merely what is probably true.
They are not defeasible like inductive arguments are, meaning no further evidence would discover could possibly undermine them.
Therefore, they can only be challenged by either rejecting the premises (denying soundness) or by denying that the conclusion follows from them with necessity (denying validity).
Such arguments rely on analytic entailment, where what is contained within a concept determines what must be true of it.
This is how the ontological argument claims that once the concept of God is properly understood, existence (or necessary existence) is entailed by it.
If God’s non-existence is a contradiction, then the proposition “God exists” is an analytic truth (true by definition).
Standard deduction operates through analytic entailment of categories.
E.g.: “All men are mortal; Socrates is a man; therefore Socrates is mortal”.
This is how certainty is preserved throughout the stages of the argument, so that we can be sure that the truth of the premises guarantees the truth of the conclusion
However in the ontological argument, the deduction proceeds not merely through categories but ‘modal’ concepts, such as possibility and necessity.
A necessary being is one that cannot fail to exist.
If such a being is even possible, then it must exist in all possible worlds, including the actual world.
The claim is that a priori reason discovers that analytic entailment functions just as decisively in this unique case.

AO1: Anselm’s ontological argument

Anselm’s ontological argument involves a purely a priori analysis of the concept of God
It’s intended to be deductive, so that the conclusion follows from the premises with necessity.
In Proslogion 2, Anselm argues:
There is a distinction between existing in the mind, and existing in reality, illustrated by the way a painter has an idea in their mind before painting it in reality
He then points to Psalm 14:1 “the fool says in his heart, ‘there is no God’”.
This shows that atheists must have an idea of the God they are rejecting in their mind.
Anselm identifies this point of agreement on the definition of God, and claims he can deduce that God exists just from God’s definition:
P1. God is defined as the greatest conceivable being.
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 think Anselm made the strongest version of the argument in Proslogion chapter 3.
Anselm introduces two new concepts:
A necessary being is one which must exist, because it does not depend on anything else for its existence.
A contingent being is one which could either exist or not, because it does depend on something else to exist.
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 later replies to critics, Anselm captures the key move of the ontological argument:
If an impossibly non-existent being is logically possible, then it must exist.

AO1: Descartes’ Ontological argument

Descartes deployed his version of the ontological argument under his rationalist epistemology.
Rationalism holds that we can gain substantive knowledge about reality purely a priori.
Anselm’s ontological argument is also a priori, but operates by proving a contradiction in God’s non-existence through formal argument.
Descartes claims one can directly apprehend God’s existence through intellectual intuition.
Anselm is often called the father of scholasticism, a medieval intellectual tradition that used systematic reasoning to examine and defend theological beliefs.
They drew on Aristotle’s logic, giving an important role to analysing propositions and constructing deductive arguments.
Propositions were often analysed as a subject (what the proposition is about) and a predicate (what is asserted of it).
Anselm’s ontological argument reflects this scholastic emphasis on logical demonstration, proceeding through a deductive proof to argue that denying God’s existence leads to a contradiction.
His conclusion that “God exists”, can be understood as ‘God’ being the subject, and ‘exists’ being the predicate.
Descartes criticised scholasticism as more useful for explaining truths already known than for discovering new truths.
For Descartes, the foundation of knowledge requires intuition, which involves direct intellectual apprehension.
We can bring ideas before our mind and apprehend truths about them due to the clarity and distinctness with which they are perceived.
He calls this the ‘natural light’ of reason, and treats such perception as a source of certainty.
Descartes illustrates intuition with it being impossible to bring a triangle before our mind whose angles do not equal 180 degrees.
He applies intuition to the idea of a supremely perfect being.
A supremely perfect being contains all perfections.
Necessary existence is a perfection, because it means God depends on nothing else for existence, and is an eternal being.
So, we can clearly and distinctly perceive that necessary existence belongs to the supremely perfect nature.
Descartes also compares the inseparability of God and existence to that of a mountain and a valley.
He acknowledges that this connection does not establish that any mountains or triangles exist.
The distinctive feature of God is that necessary existence itself belongs to God’s nature.
So, the intellectual means by which we know God’s existence has the same method and certainty as mathematical truths.
Descartes did put his argument into a deductive form, probably meant as a temporary tool to help appreciate how God can be known through intuition.
He says ‘formal argument’ is not required, but seems to think it can nonetheless help with the reflection needed to gain the right intuition:
P1: The idea of a supremely perfect being is one which contains all perfections.
P2: Existence is a perfection
C3: God exists

AO1: Malcolm’s ontological argument

Norman Malcolm’s version of the ontological argument is a priori and deductive.
It proceeds through conceptual analysis of the definition of God rather than appealing to experience.
It also employs modal logic, which studies reasoning about what is possible (could be true), necessary (must be true) or impossible (cannot be true).
Modal arguments use the logical relationships between these categories to deduce conclusions from their premises.
Malcolm uses this approach to argue that, if God’s existence is possible but cannot be contingent, it must be necessary.
Malcolm distinguishes two arguments in Anselm, the first to do with God’s existence being greater than non-existence, the second to do with God’s necessity.
Malcolm thinks Kant defeated Anselm’s argument in proslogion 2.
Since, claiming that existing in reality makes a being greater than existing only in the mind, assumes that existence adds to a thing’s concept.
However, he defends the second argument in proslogion 3, which concerns necessary existence.
He regards necessary existence as a perfection, since a necessary being is greater than a contingent being.
So Necessary existence is a predicate, and does add something to a thing’s concept.
Malcolm thinks the term ‘unlimited’ best clarifies what Anselm was getting at by describing God as the greatest conceivable being.
He takes unlimited to imply that God cannot contingently exist, since then God could cease existing, which would imply an incoherent dependence on external conditions.
Nor can God contingently not exist, since then something could create God, which would also incoherently imply that God is limited in depending on that thing.
Malcolm uses this to deduce that God necessarily exists:
P1. God is by definition an unlimited being
P2. If God exists, then God cannot cease existing, so God would exist necessarily.
P3. If God does not exist, nothing can create God, so God would be impossible
P4. God is not impossible.
C1. Therefore, God exists necessarily.
Since Leibniz, proponents of the ontological argument have accepted that it depends on God being a logically coherent concept.
Malcolm does not provide a general proof of God’s coherence, but argues that there is no special reason to presume incoherence.
He concludes that the burden of proof is on the critics of the argument to prove God impossible.
Specific allegations of incoherence should be answered individually, rather than requiring a general proof of coherence before the argument can proceed.
In any case, Malcolm’s aim is to vindicate Anselm’s original insight, that if the concept of God is coherent at all, then God must exist.

AO2: Gaunilo’s ‘lost island’ objection

Gaunilo’s ‘reductio ad absurdum’ critique argues absurdity results from applying Anselm’s reasoning to another case, like the greatest conceivable island.
Following P2, if it’s greater to exist, then that island must exist.
This would work for the greatest conceivable version of anything, absurdly implying reality would be ‘overloaded’ with greatest versions of every possible thing.
Gaunilo is denying deductive validity, because he’s denying that the conclusion of God’s existence follows from the premises.

Counter

However, Anselm replies that his argument applies uniquely to God, whose non-existence he argues is inconceivable
Descartes develops this by arguing that God’s essence includes necessary existence, whereas contingent beings like islands do not.
An island is contingent by definition (land enclosed by water), so its existence depends on things which might not exist, e.g., water, a planet, etc.
Therefore, no matter how great a contingent thing like an island is, it will still be contingent and possibly non-existent.

Evaluation

This reply defeats Gaunilo because a priori reasoning can only demonstrate the existence of a necessary being.
A priori reasoning involves analysing the definition of concepts.
When we apply this analysis to contingent beings, we can discover their existence conditions, but not whether those conditions are fulfilled.
E.g., It tells us the island depends on water to exist, but not whether that water exists, nor therefore the island itself.
By contrast, a priori analysis of a necessary being tells us that they contain their own reason for existence.
Their existence conditions do not involve anything external to them.
Therefore, there is nothing regarding the fulfilment of those conditions which is not already captured in their definition.

This explains why an a priori demonstration of existence can work exclusively for God, but not for contingent things like islands.

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.

Counter

However, 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.
Anselm makes 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.

Evaluation

This response shows that Gaunilo misunderstood P3 and demanded more understanding than Anselm’s premise requires.
Some concepts involve a hierarchy which must have a highest point, which Plantinga called its ‘intrinsic maximum’.
E.g., knowledge has an intrinsic maximum because knowing every truth would be unsurpassable.
‘Greatness’ has an intrinsic maximum, as a being with all the omni-qualities is unsurpassable.
We can understand what knowing everything means without knowing everything ourselves.
Such a being is beyond our understanding, but we can still understand that it is the pinnacle of the greatness hierarchy.
We don’t need to understand what a maximally great being substantively is in order to follow the ontological argument’s reasoning about it, that if it’s greater to exist, then it must exist.
So, Anselm’s defence works because Gaunilo overlooks the distinction between knowing God to be the greatest being, and knowing what it is to be the greatest being.
His argument only needs the former, not the latter.

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

The ontological argument claims that denying God’s existence incoherently denies what God is (a maximally great/perfect being).
Kant argues this misunderstands what existence is by treating it as a real predicate, which describes a thing’s characteristics.
He illustrates: there’s no conceptual difference between 100 coins in reality versus only in the mind.
If existence were a predicate, it would describe a characteristic of the real coins which the mental coins do not have.
But 100 coins is just 100 coins whether they exist or not, predicated by 100, round, shiny, etc.
Anselm’s premise that existing is greater or more perfect therefore assumes that existence bears on what a thing is.
Kant has distinguished what a thing is from whether it exists.

Counter

However, Descartes’ version of the ontological argument doesn’t rely on attributing existence to God as a predicate.
He criticised Anselm’s scholastic method of argumentation.
In cartesian epistemology, rational intuition can apprehend that God is inseparable from existence, just as a triangle is inseparable from three sides.

Evaluation

Furthermore, Malcolm argues Kant fails to undermine Anselm’s 2nd version.
Coins are contingent things which can exist or not, having the same conceptual description in either case.
This proves that existence ‘as such’ is not a real predicate, but doesn’t show that necessary existence isn’t a real predicate.
An unlimited being has no dependencies, and therefore cannot fail to exist.
Necessary existence is therefore a real predicate, because it characterizes a being as containing its reason for existence within itself and as impossibly non-existent.
Unlike with coins, we cannot hold God’s nature constant while comparing his existence with his non-existence.
Ultimately, Kant makes the same mistake as Gaunilo, extending a conclusion drawn from contingent things, like islands or coins, to an argument about a necessary being.

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

Gaunilo rejected inference from understanding God to God’s existence.
Malcolm argues Gaunilo misapplied this insight to a contingent Island (as did Kant’s 100 coins).
Kant’s first critique develops this insight, arguing Anselm conflated necessity in mental judgement with necessity in reality.
Here, Kant properly applies this to necessity:
A triangle necessarily has three sides, meaning if a triangle exists, then it necessarily has three sides.
Similarly, mentally defining God as predicated with necessary existence only shows that if God exists, then God exists necessarily.
This also answers Descartes’s claim God can be known intuitively through grasping of necessity in mental judgement.

Counter:

Malcolm accuses Kant of incoherently accepting God’s necessary existence as an a priori truth while also allowing that God’s non-existence is possible.
If God necessarily exists, God cannot possibly fail to exist.
Anselm & Malcolm claim a maximally great being cannot have any dependencies.
It therefore cannot contingently exist nor contingently not exist.
They infer that God either necessarily doesn’t exist (is impossible) or necessarily exists.
So if the idea of God makes sense (isn’t impossible), God must exist.

Evaluation

However, there are alternatives Malcolm has not eliminated.
Hick argues a non-contingent being could be ontologically necessary, meaning non-dependent, eternal, and self-existent (aseity).
If it exists, it cannot cease to exist and is ontologically necessary.
If it does not exist, it cannot come into existence, and is ontologically impossible.
God could either exist or not exist, without contradicting the definition of an ontologically necessary being.
A priori reasoning can specify how such a being would exist if it did, but not whether it actually does exist.
Whether God exists is therefore a ‘sheer fact’ (Hick).
So, Malcolm’s description of God as a non-contingent being at most establishes ontological necessity or impossibility.
He is left without justification for his move to God being either logically necessary or impossible.
So, Hick’s distinction between types of necessity defends Gaunilo and Kant’s insight that necessity in mental judgement doesn’t entail actual existence.

AO2: Can we rationally believe that God is possible?

Hume argues that whatever we conceive as existing, we can conceive as not existing.
Therefore, no being’s non-existence is an inconceivable contradiction.
A priori proofs require that denying their conclusion is contradictory.
So, no being’s existence can be demonstrated a priori.
Hume rejects the notion of a necessary being as incoherent.

Counter

However, apparent conceivability does not establish genuine possibility.
Plantinga distinguishes a proposition being necessarily true from its self-evidence.
God could exist necessarily even if God’s non-existence appears conceivable.
Plantinga argues it’s at least rational to accept God’s possibility, because it remains compelling even after examining critiques of God’s coherence and its connections with other beliefs.
If it’s rational to accept God’s possibility, the ontological argument shows it’s rational to accept God’s actuality.

Evaluation

However, Van Inwagen questions whether our competence in ordinary modal judgements extends to the possibility of a perfect being.
Developing this, we lack adequate grounds for trusting our judgement that knowledge and power could exist limitlessly and coexist in a necessarily existent being.
Plantinga’s confidence in God’s coherence, and the failure of critiques of God’s coherence, could both reflect the same limited ability to detect potential incoherence in the concept of God.
Plantinga needs to address these doubts, or counterbalance them with positive reasons to trust our judgement in this extraordinary case.
The metaphysically unique ‘necessarily existent’ nature attributed to God gives the argument its power to infer from possibility to actuality.
Yet this same nature also impedes justifying that possibility a priori.
Surviving critical examination supplies insufficient reassurance while our ability to detect incoherence in this exceptional case remains in doubt.
On these a priori grounds, the only rational attitude towards God’s possibility is therefore suspension of judgement.
The argument therefore fails to provide independent justification for theism.