Combining Texts

All the ideas for 'On the Question of Absolute Undecidability', 'A Completeness Theorem in Modal Logic' and 'Reference and Essence (1st edn)'

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16 ideas

2. Reason / D. Definition / 11. Ostensive Definition
18889 Ostensive definitions needn't involve pointing, but must refer to something specific [Salmon,N]
4. Formal Logic / D. Modal Logic ML / 1. Modal Logic
10163 Propositional modal logic has been proved to be complete [Kripke, by Feferman/Feferman]
4. Formal Logic / D. Modal Logic ML / 3. Modal Logic Systems / a. Systems of modal logic
10760 With possible worlds, S4 and S5 are sound and complete, but S1-S3 are not even sound [Kripke, by Rossberg]
4. Formal Logic / D. Modal Logic ML / 3. Modal Logic Systems / h. System S5
14627 S4, and therefore S5, are invalid for metaphysical modality [Salmon,N, by Williamson]
4. Formal Logic / D. Modal Logic ML / 7. Barcan Formula
16189 The variable domain approach to quantified modal logic invalidates the Barcan Formula [Kripke, by Simchen]
15132 The Barcan formulas fail in models with varying domains [Kripke, by Williamson]
4. Formal Logic / F. Set Theory ST / 1. Set Theory
17884 Mathematical set theory has many plausible stopping points, such as finitism, and predicativism [Koellner]
17893 'Reflection principles' say the whole truth about sets can't be captured [Koellner]
5. Theory of Logic / K. Features of Logics / 5. Incompleteness
17894 We have no argument to show a statement is absolutely undecidable [Koellner]
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / i. Cardinal infinity
17890 There are at least eleven types of large cardinal, of increasing logical strength [Koellner]
6. Mathematics / B. Foundations for Mathematics / 4. Axioms for Number / d. Peano arithmetic
17887 PA is consistent as far as we can accept, and we expand axioms to overcome limitations [Koellner]
6. Mathematics / B. Foundations for Mathematics / 4. Axioms for Number / g. Incompleteness of Arithmetic
17891 Arithmetical undecidability is always settled at the next stage up [Koellner]
9. Objects / D. Essence of Objects / 7. Essence and Necessity / a. Essence as necessary properties
18888 Essentialism says some properties must be possessed, if a thing is to exist [Salmon,N]
19. Language / B. Reference / 1. Reference theories
18886 Frege's 'sense' solves four tricky puzzles [Salmon,N]
19. Language / B. Reference / 3. Direct Reference / a. Direct reference
18887 The perfect case of direct reference is a variable which has been assigned a value [Salmon,N]
26. Natural Theory / B. Natural Kinds / 5. Reference to Natural Kinds
18891 Nothing in the direct theory of reference blocks anti-essentialism; water structure might have been different [Salmon,N]