The Ontological Argument

The Ontological Argument to prove the existence of God.

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The Ontological Argument


analytic (proved by definition) / synthetic (need proof). PREDICATES are words which contain ideas in them e.g. male & single of predicates of the word "bachelor". Question is what are the predicates of God- is existence one of them? Proponents of OA claim that YES: it is an ANALYTIC EXISTENTIAL PROPOSITION.

Anselm's first argument (Proslogion 2)

  • By definition God is "that which nothing greater can be conceived"
  • Both believers and non-believers understand this definition even the "fool" of Psalm 14 (considered atheist opponents as fools for disbelieving)
  • Something can exist in the mind alone or both in the mind and reality
  • It is greater to exist in the mind and in reality than to exist in the mind alone
  • Therefore God must exist in reality as well as in the mind.
  • He makes the parenthetical remark "what he understands is in his understanding"

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Gaunilo's criticism in "On behalf of the Fool"

  • I can conceive of the most real and perfect island
  • It is greater to exist in the mind and in reality than to exist in the mind alone
  • So this lost but perfect island must exist in reality as well as in the mind
  • The notion of a real and perfect island is absurd

This argument exposes a basic flaw in the OA as if the "most perfect island" is an object, according to Anselm that CAN be imagined to be non-existent, then it follows that existence itself could not be an added perfection. Hence it makes no difference to the idea of perfection, whether the object exists in reality or only in the mind. G. argues that Anselm simply defines things into existence- which cannot be done. He believed that A's argument was "unintelligible".

BUT- P1 is incoherent- the problem is the qualities which make an island are not the sort of qualities that admit of conceptually maximal qualities. i.e. no matter how great any island is in some respect, it is always possible to imagine an island greater than that island in that very respect e.g. there is no intrinsic maximum for fruit-abundance. C.D BROAD agrees with this idea. Platinga argued you could not agree what constituted a perfect island.

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Anselm's second argument (Proslogium 3)

  • He points out that God is different and that his argument and reasoning only applies to God
  • Only God can properly be the greatest possible being
  • An island is ACTUAL ,whereas God is the greatest POSSIBLE being i.e. God, by definition, must be absolutely the greatest possible being.
  • If God doesn't exist you are not imagining the greatest possible being because the idea of a non-existent greatest possible being is a contradiction in terms
  • God's existence is therefore NECESSARY. God, and only God, cannot be conceived of as not existing. Physical things are contingent and therefore couldn't exist.

This argument is different as it doesn't rely on the claim that existence is a perfection but rather necessary existence is perfection. This version is less vulnerable to Kantian criticisms as necessary existence unlike mere existence seems clearly to be a property.

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Descartes' Ontological Argument (Meditations, 5)

  • God is a supremely perfect being
  • Existence is perfection
  • As the supremely perfect being, God must possess all possible perfections, amongst which must include the perfection of existence.
  • A being that failed to exist would be less than perfect.
  • Therefore existence is a necessary attribute of the perfect being, God.
  • e.g. a triangle-> thinking about it a triangle doesn't mean the triangle exists but what I am thinking about must have 3 sides and 3 angles adding up to 180 degrees. also a mountain-> must have a valley. It is self-contradictory to deny the existence of the supremely perfect being when the attribute to existence is a necessary component of his perfection.

Argued that God's existence is his ESSENCE is his existence. He believed that whatever we clearly and distinctly perceive is true and what we clearly and distinctly perceive is that the concept of a necessary being necessitates that it exists. Existence is a predicate of God like a valley is a predicate of a mountain. "supremely perfect being" God cannot be doubted like the truths of mathematics cannot be doubted.

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Kant's criticism of the OA (Critique of Pure Reason)

  • Existence is not a predicate but rather a PRECONDITION, as both Anselm and Descartes assume. Russell uses the example of unicorns to prove that "exists" does not add anything to a description of something. It is not possible for a non-existent thing to instantiate any properties because there is nothing to which, so to speak , a property can stick.
  • All existential propositions are synthetic. Kant argues that we can only know if such propositions are true/false by experience only. - there are no necessary propositions about existence.: By saying "God exists" (an analytic statement) contradicts the idea. An analytic statement merely restates the property that is already defined in the subject i.e. they tell us nothing new. The truth of any analytic statement is then truly conditional: it does/ can not prove anything. He said it is an "unnatural procedure"
  • What is logically possible may not be possible in reality. It is true that a unicorn must have a horn but that does not mean that there are any unicorns.
  • He fundamentally criticises P3 on the basis of believing existence is not a predicate of God but rather merely the copula of a judgement.
  • Bertrand Russell also claims existence is not a property but an idea of something.
  • if one dismisses the idea of the three sides of tri and tri itself, left w/no contradic
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Aquinas's Criticism of the Ontological Argument

  • He claims we don't have an agreed definition of God. Many people have different ideas of God.
  • We can reason to God from the effects of God's action in the world. Any argument must start from experience.
  • He argued it cannot be analytic which is later reflected in his synthetic cosmological argument.
  • He rejects P2 on the grounds that although we can state "a being than which nothing greater can be conceived" we do not know what this sequence of words really mean-> God is something completely different to anything we know, so the concept of this infinitely great being dwarfs finite human understanding.
  • We never know his nature so we cannot use a definition of God to prove that he exists.
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Modern Versions of the O.A.

Platinga's version of the OA

  • Imagine there are many possible worlds: in some worlds you and I exist, in some only I exist and in others only you exist. We are all possible beings who may or may not exist and may be different from what we are. God is a being who MUST exist in every possible world.
  • A being's excellence in a given world depends only upon the properties it has in the one given world.
  • But its greatness depends on what it is like in other worlds too.
  • A being has the maximal degree of greatness in a given world, only if it has maximum excellence in every possible world.
  • It is possible that a being has maximal greatness.
  • So there is a possible being that in one world had maximal greatness.
  • A being has maximal greatness in a given world only if it has maximal excellence in every world.
  • A being has maximal excellence in a given world only if it has omniscience, omnipotence and moral perfection in that world.
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Malcom's version of the O.A. (In the "Philisophical Review" 1969)

  • He accepts that A's first version of the O.A. is faulty so focuses on his 2nd version
  • If God doesn't already exist, he cannot come into existence since this would require a cause and God doesn't have this.
  • If God already exists, he cannot cease to exist as he is eternal.
  • FROM THE STATEMENT: God necessarily exists there are 3 possibilities:
  • 1) this is impossible (not the case as there isn't a contradiction in the statement)
  • 2) it is probable (can't be the case as God is necessary)
  • 3) it is true (last option so must be the case)

He is trying to claim there is at least one analytic existential truth: God exists necessarily. He supports this by stating that if you want to understand this idea, think of EUCLID's deduction of the existence of an infinity of prime numbers. Once you have understood the principle, it remains valid.

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Analysis of the Ontological Argument


  • Keith Ward-> argument works well if you concede that it is possible to understand the idea of God i.e. it is a rational argument.
  • Malcolm-> if you are trying to show that God exists within a believing community, then the argument works i.e. the people who DO believe in Go as the greatest possible being, therefore he must exist.
  • A priori argument-> logical, doesn't rely on our unreliable sense experience which also means anyone can understand it.

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  • You can't use a prior arguments to prove that things exist. Some argue you need to see/touch things to prove it into existence. Reality depends on sense experience.
  • Assumes humans can understand what God is. Is this possible?
  • It only works if you accept the definition of God. What if you disagree with the premise in the first place?
  • This is a reduction ad absurdum argument. It sets up a definition of God which to contradict implies an absurdity so we have to accept both the definition and the conclusion. THe conclusion is implicit in the premise.
  • In Hume's Dialogues Concerning Natural Religion Cleanthes argues that no being could ever be proven to exist through an a priori demonstration.
  • Frege distinguishes between 'first' and 'second-order' predicates. First order predicates tell us something about the nature of something e.g. horses are brown. Second order predicates tell us about concepts e.g. horses are numerous. Frege's objection to Anselm and Descartes is that they both use existence as a first-order predicate whereas it's actually only a second-order.
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  • Bertrand Russel says that Anselm used the word 'exist' wrongly. Existence can't be a predicate. If it were, we could construct the argument: men exist; santa claus is a man; therefore Santa Claus exists. this is a SYLLOGISM. Existence isn't a property of things but of the IDEAS of those things. Therefore, to say that dragons do not exist is to say that, of all things that do exist, none of them are referred to by the word dragon. Russel has put Anselm's argument into different terms. He states that to label and define something is to provide an intention concerning the object under discussion.
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Useful Information :]
It may be a bit more useful if there were more colours

Otherwise its good, thank you x 

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