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The Ontological Argument

  • The ontological arguments are the only arguments for God’s existence that use a priori reasoning.
     

  • All ontological arguments are deductive arguments.​
     

  • Versions of the ontological argument aim to deduce God’s existence from the definition of God.
     

  • Thus, proponents of ontological arguments claim ‘God exists’ is an analytic truth.
     

  • They are called ontological arguments because "ontology" means the nature of being or existing.

Anselm's Ontological Argument

  • By definition, God is a being greater than which cannot be conceived​
     

  • We can coherently conceive of such a being i.e. the concept is coherent​
     

  • It is greater to exist in reality than to exist only in the mind​
     

  • Therefore, God must exist
     

  • God simply cannot only exist in the mind alone, because then you would be able to think of something greater. 
     

  • Strengths: It is a convincing and understandable definition of God that most people would agree on.
     

  • It also uses definitions to prove that God has to exist. Them being a priori means they are independent from experience.

“If you say that what is not entirely understood is not understood and is not in the understanding: say, then, that since someone is not able to gaze upon the purest light of the sun does not see light that is nothing but sunlight.”

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Good to know for OCR: Exam questions for each topic can be very specific or very vague. This was a question asked a few years ago:

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Problem: Gaunilo's Island

  • Gaunilo of Marmoutiers argues that if Anselm’s argument is valid, then anything can be defined into existence. For example:​
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  • The perfect island is, by definition, an island greater than which cannot be conceived​
     

  • We can coherently conceive of such an island i.e. the concept is coherent​
     

  • It is greater to exist in reality than to exist only in the mind​
     

  • Therefore, this island must exist
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  • Gaunilo argues that if Anselm’s argument were valid, then we could define anything into existence. This is obviously false.​
     

  • Gaunilo also argues that existence in the understanding (mental conception) is not the same as existence in reality.
     

  • Just because we can conceive of something “great” or “perfect” does not logically mean it exists in the external world.
     

  • Anselm can respond to this by claiming that these are not valid objects to apply the Ontological Argument to. God is clearly unique whose non-existence does not make sense. You cannot equate a simple island to God.

Problem: Gaunilo & Understanding God

  • Gaunilo also explains that Anselm is incorrect to claim that we are able to conceive of God at all.
     

  • God is completely unknowable and unique and thus any attempt at a genuine understanding of God is incorrect.
     

  • Anselm could respond by using an analogy to help us understand: You cannot fully look at the sun, but you can understand and see daylight. We cannot fully know God but we can understand that he is the greatest conceivable being.​

Descartes' Ontological Argument

  • I have the idea of God​
     

  • The idea of God is the idea of a supremely perfect being​
     

  • A supremely perfect being does not lack any perfection​
     

  • Existence is a perfection​
     

  • Therefore, God exists
     

  • This argument is similar to Anselm’s, except it uses the concept of a perfect being rather than a being greater than which cannot be conceived.​
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  • Descartes argues this shows that ‘God does not exist’ is a self-contradiction. 
     

  • This argument is stronger than Anselm's because it demonstrates that existence is contained within the idea of God. God and existence are inseparable. 

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Problem: Hume

  • The ontological argument says that due to the definition of God, God must exist. This would make ‘God exists’ an analytic truth.​
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  • The denial of an analytic leads to a contradiction. For example, “there is a triangle with 4 sides” is a contradiction.​
     

  • You cannot conceive of a contradiction. If you try to imagine a 4-sided triangle, you’ll imagine a square. So, you cannot conceive of an analytic truth being any other way than the way it is.
     

  • Therefore, Descartes and Anselm believed that “God does not exist” is a contradiction​.
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  • But Hume argues against this: anything we can conceive of as existing, we can also conceive of as not existing. We don't break logic by imagining God not existing in the same way we do if we try and imagine a 4-sided triangle.
     

  • This shows that “God exists” cannot be an analytic truth and so ontological arguments don't work.​
     

  • This is because if ontological arguments succeed, ‘God does not exist’ is a contradiction​
     

  • A contradiction cannot be coherently conceived​
     

  • But ‘God does not exist’ can be coherently conceived​
     

  • Therefore, ‘God does not exist’ is not a contradiction​
     

  • Therefore, ontological arguments do not succeed​

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Problem: Kant & Predicates

  • Kant argues that existence is not a predicate of things in the same way, for example green is a property of grass.​
     

  • Predicates are supposed to provide descriptive detail about the subject of a sentence.
     

  • To say something exists doesn’t add anything to the concept of it.​
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  • Imagine a unicorn. Then imagine a unicorn that exists. There is no difference between the two ideas. Adding existence to the idea of a unicorn doesn’t make unicorns suddenly exist.​ The concepts are the same.
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  • When someone says “God exists,” they are not claiming that God has the property of existence. If existence were a property, then “God does not exist” would mean “God has the property of non-existence,” which is nonsensical.
     

  • Saying that existence is a property would be like going up to someone and saying ‘You look existent today!’. It doesn’t make sense in the way other properties do.
     

  • Instead, saying “God exists” asserts that God corresponds to something in reality. This cannot be deduced from the definition of God alone; it requires empirical evidence. Therefore, the ontological argument fails to prove God’s actual existence.
     

  • This criticism is important for Anselm's OA because Anselm relies on existence proving how great something is.
     

  • However, Descartes can survive this criticism because existence is not a predicate in his argument. Rather, God and existence are inseparable in the same way a triangle and 3-sidedness are inseparable.

Normal Malcolm's Ontological Argument

  • Norman Malcolm argues that existence isn’t a predicate,  but necessary existence is. If something cannot possibly fail to exist, then that’s a genuine property. So Malcolm's version of the ontological argument avoids Kant’s objection.
     

  • This is long winded so take it step by step to make sure you're following:
     

  • Either God exists or does not exist​

  • God cannot come into existence or go out of existence​

  • If God exists, God cannot cease to exist​

  • Therefore, if God exists, God’s existence is necessary​

  • Therefore, if God does not exist, God’s existence is impossible​

  • Therefore, God’s existence is either necessary or impossible​

  • God’s existence is impossible only if the concept of God is self-contradictory​

  • The concept of God is not self-contradictory​

  • Therefore, God’s existence is not impossible​

  • Therefore, God exists necessarily

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Extra Resources

Here are some extra resources for this topic. Things like essay plans for A* answers. They are paid for, sorry! They're £2 each because they take me a really long time to make :) 

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