This argument is based on a definition of God.
If we can agree on a definition we should be able to agree on a conclusion.
No based on evidence and therefore more rational.
If the premises are sound we must accept the conclusion
De dicto – by definition
In intellectu – in the mind
Critics say existence doesn’t add anything to our understanding of God however Anselm says yes it does – to know of his existence is not the same as knowing him and one cannot know him if he does not exist.
Gaunilo‘s island – if the island is perfect it must exist because existence is a ‘perfection’ BUT it doesn’t!
Anselm said contingent things can always be added to there fore can never be perfect; only a non-contingent being cannot be added to therefore the onto argument only applies to necessary beings.
Gasking: the creation of the universe is the greatest achievement
- The greater the achievement the more impressive if the creator is limited
- The greatest limit would be non=existence
- Therefore the creation of the universe by a non-existing creator is greater than by an existing one
- Therefore God does not exist!!
- Reduction ad absurdam!!
- God can either exist or not
- If he doesn’t then not most perfect conceivable being
- If he does exist he cannot exist contingently
- Therefore he must exist necessarily.
Plantinga‘s multiverse theory depends on ‘if…’
Hume – anything we can conceive of as existing we can also conceive of as not existing
He didn’t believe there was anything which was not contingent therefore God does not exist.