- St. Anselm (1033-1109), Benedictine monk, Archbishop of Canterbury
- Developed a reductio ad absurdum argument, denying God's existence would involve adopting a nonsensical argument
- Argument is analytic: Meaning explained within itself
- Apriori: True by definition, no sensory experience needed, asks one to think logically
- Deductive: Conclusion derived from premise
- Argument's success depends on its success as a deductive proof, "Gos is the greatest possible being" is not universally accepted so the argument is flawed
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Anselm's first form
- Starts by giving a definition of God, "that than which nothing greater can be conceived"
- Even the fool can understand this
- Atheists say that God exists in intellectu (in the mind)rather than in re (in reality)
- It is greater to exist both in the mind and in reality, God must do this if the definition is true (seeks to prove God's existence is de dicto necessary - by virtue of his definition)
- Atheists would admit their mistake when they see that God must exist for the initial definition to be true
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- In (On behalf of the fool), he says that we can apply Anselm's jump from "God is the greatest possible being - God exists" to anything as long as we say it is the greatest
- He used the analogy of the most perfect island imaginable and it was structured in the same way as Anselm's argument but the conclusion was questionable. He said that for the argument to work, we must prove that God is in fact the greatest possible being rather than just by definition before we can ascribe existence to him
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Anselm's second form
- Anselm replied to Gaunilo and this argument revolves around the assumption that "God cannot be conceived not to exist...that which can be conceived not to exist is not God". As God is the greatest possible being, the idea of his nonexistence is a contradiction in terms
- This new argument defeats Gaunilo's because physical things are dependant upon other physical things for their existence whereas God's in not dependent upon anything (as shown in the cosmological argument - the uncaused cause)
- Physical things have no intrinsic maximum as they can always be improved. God is not in this category as he is atemporal and necessary rather than temporal and contingent like the island
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- He said that some things are self-evident (apriori) but in order to know these things, we must be able to define the subject and the predicate. Humans lack the intellect to define the nature of God so Anselm is wrong to offer a definition of him
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- In (Meditations on first philosophy), he said that:
- God is the supremely perfect being
- This being contains all supreme perfections
- Existence is a supreme perfection so God exists
- The argument relies upon a certain definition of God and it is assumed that the state of perfection can only come about when the predicate of existence is present
- Both Descartes and Anselm conclude that "God exists" is true by definition because the subject (God) already contains the predicate (existence).
- God is a necessary being and his nonexistence is as impossible as an uphill slope without a downhill slope, God's existence is part of his essence as the supremely perfect being
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Immanuel Kant's first criticism
- Begins by provisionally agreeing that existence is part of God's meaning and "God necessarily exists" is analytic (true by definition)
- It is possible to accept that a subject and predicate are inseparable whilst denying there is anything in reality corresponding to the subject in question. A unicorn must have a horn to avoid being a horse but we can still deny that unicorns exist
- We can only say that "if God is the supremely perfect being, he exists"
- Descartes' definition of God only tells us about the word "God" rather than anything about his existence in the world
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Kant's second criticism
- Kant expands on his first criticism, "Existence is obviously nota real predicate" (Critique of pure reason)
- He says that a genuine predicate is one that adds a descriptive property to the subject and enriches our concept of it. "Existence" does nothing to change our idea of something once we have imagined it. He asks us to imagine 100 Thalers, and then to imagine them as existing. Nothing changes.
- Kant concludes that existence is not a real predicate and if he is right, both ontological arguments fail because existence does not belong to our defrinition of God
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Bertrand Russell's criticisms
- Russell and Frege thought there was a difference between the surface structure and the true logical structure of language. They said that "exists" is not a genuine predicate and is only really a way of saying "there are some objects in this world that this concept refers to"
- "God exists" just means that there is something in the world corresponding to a particular description (omnipotent, omnibenevolent etc.)
- The ontological argument fails when we see that existence is not a property of anything. We need to find empirical evidence to say that God exists so we have an idea corresponding to our definition
- Descartes'use of the notion of necessary existence was a syllogism (all supreme beings exist, God is a supreme being, God exists)
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Norman Malcolm's argument
- Agrees with Anselm's second form saying that God's existence is necessary. However, this is ambiguous as it could mean that God's existence is a necessary truth or that God possesses a special quality called "necessary existence"
- He came up with 4 statements and said that only 1 can be true: 1) God's existence is necessarily false (logically impossible for God to exist) 2) God's existence is contingently false (God may exist but doesn't) 3) His existence is contingently true 4) His existence is necessarily true
- He said that 2) and 3) cannot be true because God is defined as the greatest possible being so he must be unlimited, independent and eternal whereas these points suggest otherwise.
- 1) only goes with statements such as "a square is round" and other such logically impossible contradictions. 4) is the only remaining possibility and means "necessary existence is a predicate of God"
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Alvin Plantinga's argument
- Criticised Malcolm's argument and came up with his own. He said that God can exist contingently without losing his independent, eternal, unlimited qualities
- "God necessarily exists" means that God exists in every possible world because the greatest possible being would have maximal greatness. To do this, the being would have to exist in every world we can imagine because this is better than existing in just some possible worlds. Therefore, God necessarily exists.
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- Unlikely to convert an Atheist, more an exploration of what God means to the theist
- Apriori and deductive arguments completely succeed or fail, this argument does not make God's existence any more probable than it was before
- Enables us to see how God's existence differs from other things i the world, presents non-believers with a fuller understanding of what theists mean when they talk about God
- Karl Barth: Anselm's argument should be seen as an exploration of faith rather than an attempted proof
- Proslogion: "I do not seek to understand so that I may believe, but I believe in order to understand"
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