Combining Texts

All the ideas for 'What is so bad about Contradictions?', 'The Concept of Logical Consequence' and 'Proslogion'

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14 ideas

2. Reason / B. Laws of Thought / 3. Non-Contradiction
Someone standing in a doorway seems to be both in and not-in the room [Priest,G, by Sorensen]
5. Theory of Logic / B. Logical Consequence / 1. Logical Consequence
Split out the logical vocabulary, make an assignment to the rest. It's logical if premises and conclusion match [Tarski, by Rumfitt]
5. Theory of Logic / B. Logical Consequence / 4. Semantic Consequence |=
X follows from sentences K iff every model of K also models X [Tarski]
5. Theory of Logic / J. Model Theory in Logic / 1. Logical Models
A 'model' is a sequence of objects which satisfies a complete set of sentential functions [Tarski]
19. Language / E. Analyticity / 1. Analytic Propositions
Sentences are 'analytical' if every sequence of objects models them [Tarski]
28. God / B. Proving God / 2. Proofs of Reason / a. Ontological Proof
An existing thing is even greater if its non-existence is inconceivable [Anselm]
Conceiving a greater being than God leads to absurdity [Anselm]
Even the fool can hold 'a being than which none greater exists' in his understanding [Anselm]
If that than which a greater cannot be thought actually exists, that is greater than the mere idea [Anselm]
A perfection must be independent and unlimited, and the necessary existence of Anselm's second proof gives this [Malcolm on Anselm]
The word 'God' can be denied, but understanding shows God must exist [Anselm]
Guanilo says a supremely fertile island must exist, just because we can conceive it [Anselm]
Nonexistence is impossible for the greatest thinkable thing, which has no beginning or end [Anselm]
28. God / B. Proving God / 2. Proofs of Reason / b. Ontological Proof critique
Anselm's first proof fails because existence isn't a real predicate, so it can't be a perfection [Malcolm on Anselm]