The Ontological Argument

  • Created by: lianne_bb
  • Created on: 04-01-17 16:17

Gaunilo's Lost Island

  • According to Anselm's logic, there can also exist a "perfect island"
  • The island is "the greatest that could ever be conceived"
  • The idea of the perfect island exists in the mind, but it is greater if it exists in reality
  • However, no such island exists; many different people have their own idea of what the "perfect island" consists of
  • The concept only exists in our minds, not reality, therefore it does not exist
  • Although a believer in God like Anselm, he disagreed that anselm's logic could be enough to prove God's existence
  • However, Anselm responded to this challenge, stating that Gaunio had not understood his premise
  • Gaunilo had compared an island (something that may or may not exist; contingent) to God (who is necessary)
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Gaunilo's Criticism

  • A French monk and Anselm's contemporary
  • He writes "on behalf of the fool"
  • Challenges Anselm's argument with three things:
  • 1.) His argument is based on unreliable "gossip" - what people think of is not necessarily the truth; words can be twisted
  • 2.) You cannot simply define a being into existence - it is thinking unreliably and makes it seem as though God is imaginary
  • 3.) He uses his example of The Lost Island, using the same 'reductio ad absurdum' reasoning as Anselm did to try and prove his logic was flawed
  • Anything can be thought to be perfect
  • If any of these arguments is sound then they all are, but they are not
  • Each of these Ontological arguments follows the same logic, so they must therefore be unsound 
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Strengths of the Ontological Argument

1.) It is a deductive argument, and therefore logically persuasive; if we accept the first premise then we must accept the conclusion 

2.) If existence was a perfection/predicate then to deny the conclsion that "God, a supremely perfect being exists" would be a contradiction

3.) The premise 'it is better to exist in mind and reality then in mind alone' is persuasive as it is true; as contingent beings we may or may not have come into existence, but it is far better than just being an idea in one's mind

4.) If's Plantinga's theory of possible worlds, with its premises, is accepted it does conclude with the God of classical theism 

5.) Anselm's work can be seen as a "demonstration" of how self-evident God's existence was to him, rather than a "proof" - he wrote in reflection of his own faith, he did not necessarily speak for the opinions of everyone else

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Weaknesses of the Ontological Argument

1.) The premises of an a priori argument are based on pure logic without experience of the world, which makes it very hard to be convincing as we always observe

2.) Gaunilo is accurate in saying that we cannot define anything into existence; and Kant establishes that existence itself does not add to what we already know about a being or object, i simply just states something exists but without any empirical evidence

3.) Just because the idea of God is in the mind does not necessarily mean that the idea has to exist in reality

4.) The Ontological argument treats any statement of God's existence as a synthetic statement, but nothing about God can be proven directly; the concept of God is too big

5.) This argument rather tries to determine the existence of the God of Philosophy rather than the God of Theism; even if this argument does prove a God, it does not prove a God that is omnibenevolent or omnipotent etc. it only proves a God of cold logic

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Anselm's First Form

  • Writes to the "fool" in his Proslogion; written as a prayer rather than an argument
  • Defines God as "that than which nothing greater can be conceived"
  • God exists as an idea in the mind (in intellectu)
  • God can exist in just the mind alone or in reality as well (in re)
  • It is far greater to exist both in the mind and reality
  • If God is "that than which..." then he must exist in reality because if he was not then we would be able to imagine something greater than God, but we cannot
  • Therefore God exists
  • Uses the analogy of the Painter and the Painting: the painting in the painter's mind alone lacks full perfection and understanding, it is only when the painting is complete that is perfect
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Anselm's Second Form

  • Similar to his First but focuses on Contingency vs. Necessity in Proslogion 3
  • God is "that than which nothing greater can be conceived"
  • God can either exist necessarily (without cause of something else) or contingently (can exist or cannot; caused by something else already in existence)
  • It is greater to exist necessarily rather than contingently
  • If God is "that than which..." then he must exist necessarily because if he did not we would be able to imagine something greater than God, but we cannot
  • Therefore God exists necessarily and in reality
  • Reductio ad Absurdum: If he does exist in the mind alone then he is not "that than which..."
  • To reject God we must have a concept of what he is, and to reject him is contradictory - "the fool says in his heart, there is no God." (Psalm 14)
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  • Tries to prove God's existence by "virtue of the definition of God"; "De Dicto" - (St. Anselm)
  • It is the study of "being" (Ontos)
  • The only a priori argument for the existence of God (based on logic, no empirical evidence)
  • An Analytic argument - either true or false by definition
  • A Deductive argument - reasoning by logical stages (premises) to reach a conclusion
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Hume's Criticism and Vardy's Middle ground

  • Hume held that you cannot take an idea in your mind, apply logic to it, and reach a conclusion based on the external, observable universe
  • Like Kant, he also held that you can't treat existence as a predicate 
  • Objection 1: You cannot prove anything a priori (as Aquinas had stated); we all base our lives around observation, and it would be unreliable for us to just assume 
  • Objection 2: You cannot be defined into existence; assumed perfections cannot be definitive proof of existence
  • Vardy says the problem is that we don't know what we're saying when God exists - we all deal with it in different ways
  • Do we see God as an object of some description? Or as a concept? (eg: a bear or a triangle)
  • If we see him as an object it doesn't work; if we see him as a concept it does work
  • If God is seen as some sort of idea or reality in the lives of people then it may have some value 
  • Like the equator and numbers - these things are useful but they are not visible objects or tangible things
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Norman Malcolm

  • American Philosopher in support of the Ontological argument
  • He holds that the statement "God necessarily exists" is either possible, impossible or necessary
  • It cannot be just possible as that implies that God may or may not exist; if God does not already exist he cannot come into existence
  • Similarly, if he does exist he cannot stop existing as that would make him contingent
  • The statement cannot be impossible as for something to impossible it would have to be logically absurd and/or incomphrehensible or contradict itself
  • The statement makes sense and does not contradict, therefore it is not impossible
  • Therefore the statement must be necessary; God must exist necessarily
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Descartes' Argument

  • Because God is a "Supremely Perfect Being" he possesses all perfections (predicates)
  • This perfect state includes existence - as a predicate
  • Existence is a perfection in itself, so if God possesses all perfections and existence is one of them then God must exist
  • He uses the example of a triangle: we cannot imagine a triangle without having 3 sides as it would no longer be a triangle - he also uses the idea that you cannot have a mountain without a valley beneath it 
  • Just as he claims existence is a predicate for God; it is inconceivable any other way

1.) Whatever belongs to the essence of something cannot be denied of it   2.) God's essence includes existence   3.) Therfore existence must be affirmed by God

1.) It cannot be applied to objects affected by time and space   2.) It can only apply to something that is perfect   3.) Only God can have absolute perfection - there cannot be two absolutes

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Descartes' Perfect Being

Predicate - A quality which intrinsically belongs to something 

  • Decartes set his argument out in his Meditations, seeking to prove God's existence through reason alone
  • He doubted all his knowledge, including his own existence - 'Cogito, ergo sum' ("I think, therefore I am."); his argument follows:
  • I exist
  • In my mind I have the concept of a perfect being
  • As an imperfect being, I could not have conjured up the concept of a perfect being 
  • The concept of a perfect being must therefore have originated from the perfect being itself
  • A perfect being must exist in order to be perfect
  • Therefore a perfect being exists
  • He translates this thinking to the question of God's existence, naming him the "Supremely Perfect Being"
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Kant's Criticism

  • He estabilishes that there is a difference between Analytic (true/false by definition) and Synthetic (requires solid evidence to make it true) statements
  • Any statement such as "God has necessary existence" is synthetic as it cannot be directly proved
  • Kant says this kind of statement is synthetic because it needs to be verified to see if it is true or false; we would need other means to verify a statement like this 
  • The statement, like the concept of God, is beyond human understanding
  • He also establishes that existence is not and cannot be a predicate
  • He agrees with Descartes' Triangle example but says that adding "...has existence" onto the end of a statement does not make it true
  • It does not add to the information we already have
  • Therefore we cannot come further to a solid conclusion as we still lack evidence
  • So existence cannot be a prediecate
  • However, Kant does not conclude saying that God does not exist, only that he disagrees with the arguments presented for this case
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Aquinas' Criticism

  • He states that no one has a correct or universally accepted concept of God
  • God's existence cannot be regarded as self-evident
  • The concept of God is so transcendant to human understanding that we can't possibly allow our mere human ideas to prove his existence
  • Our own ideas of God may conflict with others' ideas of God
  • As such we need to be able to experience God (a posteriori) in order to have certainty of his existence and to understand 
  • Aquinas' problem with Anselm's argument is that he treats a synthetic proposition as if it were an analytic one
  • God is so beyond us that it would not be accurate or logical to try and make assumptions about him 
  • He claims that a priori arguments are unsuccessful because we cannot define him, we can only know him through his work
  • Aquinas' criticism devastated Anselm's original argument so badly that it was not studied until Descartes' version revived it
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