The Ontological Argument (AQA A-Level Religious Studies): Revision Notes
The Ontological Argument
Key concepts to understand
Before examining Anselm's Ontological Argument, you need to understand several important philosophical terms. These terms define how the argument works and form the foundation for understanding both its structure and its criticisms.
A priori and a posteriori
A priori: Arguments that rely on logical deduction, not sense experience. Knowledge that comes before or prior to experience.
A posteriori: Arguments that depend on sense experience. Think of 'posterior' meaning behind or after experience.
Example: Determining Types of Knowledge
The statement "oak trees grow from acorns" can only be known through sense experience (a posteriori), not through logic alone. You must observe oak trees and acorns in the real world to know this is true.
Deductive and inductive
Deductive argument: If the premises are true, then the conclusion must be true. The conclusion is guaranteed by the premises.
Example: Deductive Reasoning
- P1: All horses have manes
- P2: A Suffolk Punch is a horse
- C: Therefore Suffolk Punches have manes
If both premises are true, the conclusion is logically guaranteed.
Inductive argument: The conclusion is probabilistic - its truth cannot be guaranteed by the premises.
The Ontological Argument is an a priori, deductive argument claiming to prove God's existence through logic alone, without any reliance on sense experience.
Analytic and synthetic
Analytic statements: True by definition - true because of the meaning of the words used.
Example: Analytic Truth
"A bicycle has two wheels" is analytic because a bicycle is defined as a two-wheeled vehicle. The predicate (has two wheels) is contained within the subject (bicycle).
Synthetic statements: Truth or falsity determined by sense experience.
Example: Synthetic Truth
"William has a hairy chest" requires observation to verify. You cannot know this just from understanding the meaning of the words.
Subject and predicate
Subject: Who or what a sentence is about.
Predicate: Information given about the subject.
In the sentence "George played the piano", George is the subject and "played the piano" is the predicate. This distinction becomes crucial in Anselm's argument when considering whether existence is a predicate of God.
Necessary and contingent
Understanding the distinction between necessary and contingent truths is fundamental to grasping Anselm's argument and his response to critics.
Necessary truth: A proposition that could not possibly be false.
Examples: Necessary Truths
- - mathematically necessary
- "Squares have four sides" - true by definition
Contingent truth: A proposition that happens to be true but might have been otherwise.
Example: Contingent Truth
"UK police cars use blue flashing lights" - they could have been red, green, or any other color. This truth is dependent on decisions made by authorities, not on logical necessity.
Necessary thing: Something that could not possibly have failed to exist.
Some philosophers argue the laws of mathematics exist necessarily - they couldn't fail to exist and apply in any possible world.
Contingent thing: Something that does not exist necessarily and could have failed to exist.
Most things in the universe, including people, planets, and even galaxies, are contingent. They happen to exist, but there's no logical necessity to their existence.
The basis of Anselm's argument
The term 'ontological' comes from the Greek word 'ontos', meaning essence, existence or being. Anselm developed his eleventh-century argument based on a key claim: God's existence can be deduced from his definition. Once God is correctly defined, there can be no doubt that he exists.
Core claims of the Ontological Argument
Three Fundamental Claims:
- The proposition "God exists" is a priori/deductive - it can be known without sense experience, just by thinking about God's nature
- In the proposition "God exists", the subject (God) contains the predicate (exists), so God must exist
- God's existence is a necessary truth, not a contingent one
Anselm's Ontological Argument: Part 1
Anselm (c.1033-1109) was a Benedictine monk and Archbishop of Canterbury. His argument appears in Proslogium Chapters 2-4 and his Responsio to Gaunilo.
Anselm's definition of God
Anselm's Central Definition:
"God is... a being than which nothing greater can be conceived."
This definition means God is the greatest in every possible respect. God must possess every great-making quality (omnipotence, omniscience, omnipresence, perfect goodness, etc.) to the highest possible level.
The argument from Proslogium 2
Anselm's first version of the argument proceeds through careful logical steps:
P1: God is a being than which nothing greater can be conceived.
P2: This definition can be understood in the mind, even by someone who does not believe God exists (like the "fool" in Psalm 14:1 who says "There is no God").
P3: There is a difference between having an idea in the mind and knowing that this idea exists in reality.
P4: Example - A painter has an idea of what to paint in his mind. When painted, the idea exists both in his mind and in reality.
P5: It is greater to exist both in the mind and in reality than to exist only in the mind.
P6: If God existed only in the mind, we could think of something greater - namely a God who existed in reality also.
C: Therefore, to be the greatest conceivable being (P1), God must exist both in the mind and in reality.
Simplified version
The argument can be reduced to its essential structure:
The Core Logical Structure:
P1: God is the greatest conceivable being.
P2: It is greater to exist in reality than to exist only in the mind.
C: Therefore, as the greatest conceivable being, God must exist in reality.
This simplified version captures the essence of Anselm's reasoning: if we can conceive of the greatest possible being, that being must possess existence in reality, otherwise we could conceive of something greater.
Gaunilo's criticism: On Behalf of the Fool
Gaunilo was a contemporary Benedictine monk who wrote a response to Anselm. He used a method called reductio ad absurdum (reduction to absurdity) to show the argument's flaw.
The perfect island argument
Gaunilo applied Anselm's logic to a "perfect lost island":
P1: It is possible to conceive of the most perfect and real lost island.
P2: It is greater to exist in reality than to exist only in the mind.
C: Therefore the most perfect and real lost island must exist in reality.
Gaunilo's point
Gaunilo's Critique:
Gaunilo argues that we can use Anselm's logic to prove the existence of any perfect object - perfect islands, perfect cricket bats, perfect oak trees. Since we know a perfect island does not exist in reality, Anselm's argument must be flawed.
The criticism shows that if Anselm's reasoning works, it proves too much - it would prove the existence of all sorts of perfect things we know don't exist.
Anselm's reply to Gaunilo: Part 2
Anselm's response comes from Proslogium 3 and his Responsio. He identifies a crucial difference between God and islands that rescues his argument from Gaunilo's criticism.
The key difference: necessary vs contingent existence
From Proslogium 3:
"God cannot be conceived not to exist - God is that, than which nothing greater can be conceived - That which can be conceived not to exist is not God."
Anselm argues that there is a fundamental categorical difference between God and all other things:
- Everything on a "perfect" island is contingent - it can exist or not exist
- A beautiful palm tree will eventually rot; a bar will weather and fall apart
- It is impossible to quantify perfection for an island - How many trees make it perfect? What is the perfect drink? What is the perfect temperature?
Anselm's counter-argument
Anselm demonstrates why the island analogy fails:
P1: To be perfect, an island would have to be "that island than which no greater can be conceived".
P2: An island than which no greater can be conceived would have to exist necessarily, since a contingent island would be less perfect than one that existed necessarily.
P3: But islands are contingent, and so cannot exist necessarily.
C: Therefore the logic of the argument related to a perfect island does not apply to God.
Further development
Anselm's Refined Argument:
P1: God is the greatest conceivable being.
P2: The greatest conceivable being cannot be conceived not to exist.
C: Therefore, God, and God alone, possesses necessary existence - God cannot not exist.
Anselm successfully refutes Gaunilo by showing that necessary existence is a predicate only of God, not of things. Islands, trees, cricket bats - all contingent objects - can be conceived not to exist, so they cannot be the "greatest conceivable being."
Kant's criticisms
Immanuel Kant (1724-1804) was an influential German philosopher whose criticisms of the Ontological Argument remain the most powerful objections to it. His criticisms were directed at René Descartes' version of the Ontological Argument (mid-seventeenth century), but they also apply to Anselm's version.
Importantly, Kant is not offering direct criticism of Anselm's argument, but of Descartes' version. However, the objections translate effectively to Anselm's formulation.
Objection 1: Existence is not a predicate
Descartes argued that God, as the "supremely perfect being", must possess all perfect predicates including existence. Descartes compared it to how a triangle must have three angles equalling two right angles - existence cannot be separated from God's essence.
Kant's Response:
Existence is not a real predicate because it adds nothing to the concept of a thing.
Explanation: Real predicates give us new knowledge about a subject. If you describe a cow as an Aberdeen Angus, you gain useful knowledge about its breed, characteristics, and qualities. But if you then say "the cow exists", nothing new has been added to your understanding of what the cow is like.
The Thalers Example:
Kant asked us to imagine 100 Thalers (coins). You can describe their predicates:
- Round
- Metallic
- Gold
- A certain weight
- A certain diameter
Each predicate adds to our concept of what the Thalers are like. But saying "the Thalers exist" adds nothing - there is no difference between the concept of 100 Thalers and the concept of 100 Thalers that exist.
The concept remains identical whether the Thalers exist or not. Existence doesn't change what we understand about the Thalers themselves.
Applied to God: When Anselm says God is the greatest conceivable being with all perfect predicates, each predicate (omnipotence, omniscience, perfect goodness, etc.) adds to our concept. But saying "God exists" adds nothing - there is no difference between our concept of God and our concept of a God that exists.
Key Point:
The only way to know that Thalers or God really exist is by sense experience, not logic alone. Existence is determined by observation and experience, not by definition or logical deduction.
Objection 2: Necessary existence as definition doesn't prove real existence
This objection can be understood through a series of logical steps that reveal a critical flaw in the argument:
Step 1: Anselm's argument claims "God exists necessarily" is analytic (true by definition).
Step 2: Compare this to other analytic statements:
- "A bachelor is an unmarried man" - true by definition
- "A unicorn is a horse with a horn" - true by definition
Step 3: Consider these propositions:
- Bachelors exist
- Unicorns exist
How do we know bachelors exist? Only by experiencing them. How do we know unicorns exist? We don't - we have never experienced them. We can only discover their existence through sense experience, never through logic.
Step 4: Applied to God: If "God exists necessarily" is analytic/true by definition, we can only know there is a God by experiencing God. Some claim to have experienced God, but this is a matter of experience, not logic.
Step 5: The Clearer Version
- "A unicorn is a horse with a horn" is logically true because that's how we define unicorns, but it does not follow that unicorns really exist.
- Equally, "God exists necessarily" is logically true because that's how we define God, but it does not follow that God really exists.
The definition tells us what something would be like if it existed, not whether it actually exists.
Step 6: The Missing Word - "If"
The argument fails because it omits one crucial word: "If"
- With unicorns: If there are unicorns, then they will be horses with horns.
- With God: If there is a God, then God will exist necessarily.
The argument proves what God would be like if God existed (necessarily existing), but not that God actually exists.
Strengths of Anselm's argument
Despite the powerful criticisms, Anselm's argument possesses several notable strengths that have kept it relevant in philosophical discussion for nearly a thousand years.
It is a deductive argument
If it succeeds, it provides proof of God's existence. Unlike the Design or Cosmological Arguments, it does not depend on potentially unreliable human observation of the natural world. The argument either succeeds or fails by its logic - there is no ambiguity or room for interpretation based on empirical evidence.
This gives it a unique status among arguments for God's existence. If valid, it would provide absolute certainty rather than probability.
Alternative interpretation: faith seeking understanding
Karl Barth argued that Anselm never intended the argument as a logical proof for atheists. Instead, it was the result of a religious experience in which God revealed his nature to Anselm. For those with faith, the argument expresses their faith rather than proving God exists.
This interpretation sees the argument as having value for believers seeking to deepen their understanding, rather than as a tool for converting non-believers.
Educational value
The argument is useful for learning philosophical concepts like the difference between:
- Analytic and synthetic propositions
- Necessary and contingent beings
- A priori and a posteriori reasoning
- How to analyse logical arguments
Many philosophy students study the Ontological Argument not because it succeeds, but because understanding it and its criticisms develops crucial analytical skills.
Weaknesses of Anselm's argument
Kant's objections appear decisive
The Scholarly Consensus:
Most scholars reject the Ontological Argument based on Kant's two objections:
- Existence is not a predicate - saying something exists tells you nothing about it that you haven't learned from sense experience
- Even if "existing necessarily" is part of what we mean by God, it doesn't follow that God exists in reality
Kant's objections don't disprove God's existence - they make it extremely unlikely that God's existence can be proved by logic.
The problem of defining God
Some argue that any attempt to define God limits God. Anything that can be classified and analysed can be understood by humans. Thomas Aquinas, the great Catholic theologian, insisted we do not know God's definition, so Anselm must be wrong.
However, you could argue that saying God is "that than which nothing greater can be conceived" means God has no limitation at all - a concept we can understand without limiting God. The definition points to God's unlimited nature rather than restricting it.
The status of Anselm's argument as a 'proof'
To understand whether Anselm's argument constitutes a genuine proof, we need to compare it with other types of arguments and proofs.
The Design Argument is inductive - it cannot be a proof because all inductive arguments are probabilistic. People may or may not observe design in the universe, and the conclusion is only probable, not certain.
Anselm's Ontological Argument is completely different:
- It is deductive rather than inductive - in a deductive argument, if the premises are true, the conclusion is guaranteed
- It is a priori rather than a posteriori - it claims to be true without using any fallible sense experience
- Anselm argues "God exists necessarily" is analytic - true by definition/logically true
- Therefore, if the premises are true, it is a proof of God's existence
Is it actually a proof?
The Ongoing Debate:
This is disputed:
- Various scholars claim it works (including Anselm, Descartes, and Alvin Plantinga)
- Most scholars argue it does not work
- Kant's objections show it merely demonstrates that "If" God exists, then he exists necessarily
The Mathematical Proof Test:
Compare it to mathematical proof () - nobody doubts mathematical proofs, but many doubt the Ontological Argument. If it was really a proof in the same sense as mathematical proofs, there would be no doubt about its conclusion.
The fact that intelligent, rational people continue to disagree about whether it works suggests it may not be a proof in the strongest sense.
Some argue it is a proof in Karl Barth's view, as a faith-based acceptance rather than a logical demonstration for all rational beings.
The value of Anselm's argument for religious faith
Beyond its status as a logical proof, we must consider what value the argument might have for religious believers and the life of faith.
Anselm's view on understanding God
In Proslogium Chapter 4, Anselm argues that a thing may be conceived in two ways:
- When the word signifying it is conceived
- When the thing itself is understood
Example: Fire and Water
The statement "fire is water":
- The words can be understood without difficulty
- But someone who really understands fire and water cannot understand fire to be water
The words make grammatical sense, but true understanding reveals the contradiction.
Applied to "There is no God":
- The words can be understood
- But once you truly understand that God is "that than which a greater cannot be conceived", you must understand that this being exists
Anselm's Claim:
The God the atheist does not believe in is not the God of Christian faith. The atheist does not have an adequate concept of God.
Anselm concludes with a prayer thanking God for illumination, saying that what he formerly believed, he now understands through God's revelation.
Issues with Anselm's view
- If the atheist lacks an adequate concept of God, what stops the atheist claiming Anselm invented his concept? The definition still doesn't prove such a being exists in reality
- Anselm seems to suggest God gave him a religious experience through "illumination" that atheists lack
- Perhaps Anselm means religion has ultimate value, and atheists should make every effort to "believe in" God, not just debate whether they "believe that" God exists
Karl Barth's interpretation: faith seeking understanding
Karl Barth (1886-1968) was a Swiss Protestant theologian who insisted God can only be known by revelation, not logic. In 1931, he wrote "Faith Seeking Understanding" about Anselm's argument.
Barth's Central Claim:
Anselm never intended a logical proof of God's existence. The Ontological Argument was Anselm's way of trying to understand the God he already believed in.
Barth's argument:
- Anselm states in Proslogium 1: "I do not seek to understand that I may believe, but I believe in order to understand"
- For Anselm, belief in God comes before reasoning about God
- Anselm began with prayer, asking God to reveal himself
- God revealed his name to Anselm: "that than which nothing greater can be conceived"
- This definition was not based on logic - it was given through religious revelation
- If humans could prove God by logic alone, we wouldn't need God's revelation, and God would become just another object of human knowledge
Arguments against Barth's interpretation
Challenges to Barth's View:
- Anselm's Proslogium addresses the "fool" of Psalm 14:1 who says there is no God. If not intended as a logical proof for the atheist, why demonstrate it so thoroughly?
- In the preface, Anselm mentions looking for a proof, not just reinforcing a revelation
- Gaunilo bothers to respond with logical objections - if Anselm was just sharing his faith, why would Gaunilo object? Their exchange is clearly a logical debate, not a discussion about faith
Other considerations
The argument may have value for those who already believe in God, as they might be more likely to accept it as a logical proof - their faith predisposes them to find the reasoning convincing.
However, fideist Christians disagree. Fideism is the view that faith does not depend on reason. Fideists might reject any attempt to "contain" God within logic.
If we could prove God logically, faith would lose its value - we wouldn't need faith if God's existence was logically guaranteed. Faith involves trust and commitment beyond what can be proven with certainty.
Anselm's final position
Despite seeking logical proof, Anselm does not try to replace faith with logic. For Anselm, faith is a volitional state (an act of will) motivated by love of God and a drive to act as God wills.
"Faith seeking understanding" means: an active love of God seeking a deeper knowledge of God.
In other words, for Anselm, belief in God comes before reasoning about God.
Exam tips
Examination Success Strategies:
- Always explain technical terms clearly before using them in your answer - don't assume the examiner knows you understand terms like "a priori" or "contingent"
- When discussing Anselm's argument, distinguish between Part 1 (Proslogium 2) and Part 2 (reply to Gaunilo)
- Remember that Kant's criticisms target Descartes' version, not directly Anselm's, though they apply to both
- For evaluation questions, use Kant's objections as strong criticisms - they are the most powerful and widely accepted objections
- Consider both logical and faith-based interpretations of the argument's purpose - this shows sophisticated understanding
- When discussing whether it's a "proof", compare it to mathematical proofs and note the ongoing scholarly disagreement
Summary
Key Points to Remember:
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The Ontological Argument attempts to prove God's existence through definition alone, using a priori, deductive reasoning - no empirical evidence required
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Anselm defines God as "that than which nothing greater can be conceived" - the greatest possible being must exist in reality, not just in the mind, because existing in reality is greater than existing only as an idea
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Gaunilo's "perfect island" criticism fails because islands are contingent (can be conceived not to exist), while only God has necessary existence (cannot be conceived not to exist)
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Kant's two objections seriously challenge the argument:
- Existence is not a real predicate - saying something exists tells you nothing about it that you haven't learned from sense experience
- Even if "existing necessarily" is part of what we mean by God, it doesn't prove God actually exists - it only tells us what God would be like if God existed
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The argument's status as a "proof" is disputed - if it were truly a proof like , there would be no doubt, yet scholars continue to disagree
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The argument may have value for religious faith as "faith seeking understanding" (Barth's interpretation) rather than as a logical proof for atheists
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Understanding the technical vocabulary (a priori/a posteriori, analytic/synthetic, necessary/contingent, deductive/inductive) is essential for grasping the argument's structure and criticisms