Ontological Argument

Question 1

What is the ontological argument?

Answer 1

• The ontological argument is based on the claim that God’s existence can be deduced from his definition, once God is correctly defined, there can be no doubt that he exists.
• The ontological argument claims that the proposition ‘God exists’ is a priori and deductive, you do not need sense experience to know that it is true, you know it is true just by thinking about it.
• In the proposition ‘God exists’, the subject ‘God’ contains the predicate ‘exists’, so God must exist.
• It is as clear as knowing that bicycles (subject) have wheels (predicate).
• God’s existence is a necessary truth, not a contingent one.

Question 2

What is Anselm’s argument in premises?

Answer 2

• P1 – God is a being than which nothing greater can be conceived.
• P2 – This is a definition which even a fool understands in his mind, even though he does not understand it to exist in reality.
• P3 – There is a difference between having an idea in the mind and knowing that this idea exists in reality.
• P4 – For example, a painter has an idea in his mind of what he wants to paint, but when he has painted it, that idea now 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, I could think of something greater, namely a God who existed in reality also.
• C – Therefore in order to be the greatest conceivable being, God must exist both in the mind and in reality.

Question 3

What is Gaunilo’s criticism?

Answer 3

• Uses a parody of Anselm’s argument to show that it is absurd
• 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.
• So Gaunilo is saying that the real fool would be anybody who argued in this way.

Question 4

What is Anselm’s reply to Gaunilo?

Answer 4

• P1 – To be perfect, an island would have to be ‘that 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 an island that existed necessarily.
• P3 – But islands are contingent so cannot exist necessarily.
• C – Therefore, the logic of the argument related to the perfect island does not apply to God.
• Further,
• P1 – God is the greatest conceivable being.
• P2 – The greatest conceivable being cannot be conceived not to exist.
• C – Therefore, God, and God aloe, possesses necessary existence, God cannot not exist.
• In summary, Anselm gives a clear refutation of Gaunilo’s ‘perfect lost island’ argument.
• He shows that necessary existence is a predicate only of God, and not of things.

Question 5

What are the criticisms from Kant?

Answer 5

• Criticism – Existence is not a predicate
  o God must possess all the perfect predicates such as omnipotence and omniscience and necessary existence.
  o But existence is not a real predicate, so if we list all of God’s predicates and then add ‘existence’ we add nothing new to the concept of God.
  o The only way I can know that Thalers exist is to experience them, so the only way I can know that God exists is by sense experience, not by logic.
• Criticism – We can accept that ‘necessary existence’ is part of what we mean by ‘God’, but it does not follow from this that God exists in reality.
  o ‘A unicorn is a horse with a horn’ is logically true, because that’s how we define a unicorn, but it does not follow from this that there really are any unicorns.
  o Equally, ‘God exists necessarily is logically true, because that’s how we define God, but it does not follow that there really is a God.
  o If there are unicorns, then they will be horses with horns, if there is a God, then God will exist necessarily.

Question 6

What are the strengths of the Ontological Argument?

Answer 6

• Kant, existence is not a predicate
• Argument is deductive, so if it works, it is a proof.
• Karl Barth, the argument succeeds because it is not meant to be a logical proof, it is a confession of faith, for those who have faith, the argument is clear to their faith.

Question 7

What are the weaknesses of the Ontological Argument?

Answer 7

• Most agree that Kant’s two objections defeat all Ontological Arguments, they do not disprove the existence of God, but they do show that God’s existence cannot be shown by logic.
• Some reject Anselm’s definition such as Aquinas who states that, any attempt to define God limits him.

Question 8

What value does the Ontological Argument have for faith?

Answer 8

• Argument has value for those who believe in God already, since they are more likely to accept it as a logical proof.
• But many Christians disagree about the last point, fideists would argue that if we could prove God’s existence by logic, faith would lose all its value.