Combining Texts

All the ideas for 'On the Question of Absolute Undecidability', 'A Note on the entscheidungsproblem' and 'Law and Causality'

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12 ideas

4. Formal Logic / F. Set Theory ST / 1. Set Theory
Mathematical set theory has many plausible stopping points, such as finitism, and predicativism [Koellner]
'Reflection principles' say the whole truth about sets can't be captured [Koellner]
5. Theory of Logic / K. Features of Logics / 5. Incompleteness
We have no argument to show a statement is absolutely undecidable [Koellner]
5. Theory of Logic / K. Features of Logics / 7. Decidability
Validity is provable, but invalidity isn't, because the model is infinite [Church, by McGee]
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / i. Cardinal infinity
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
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
Arithmetical undecidability is always settled at the next stage up [Koellner]
10. Modality / B. Possibility / 8. Conditionals / d. Non-truthfunction conditionals
Ramsey's Test: believe the consequent if you believe the antecedent [Ramsey, by Read]
10. Modality / B. Possibility / 8. Conditionals / e. Supposition conditionals
Asking 'If p, will q?' when p is uncertain, then first add p hypothetically to your knowledge [Ramsey]
14. Science / B. Scientific Theories / 8. Ramsey Sentences
Mental terms can be replaced in a sentence by a variable and an existential quantifier [Ramsey]
26. Natural Theory / D. Laws of Nature / 4. Regularities / b. Best system theory
All knowledge needs systematizing, and the axioms would be the laws of nature [Ramsey]
Causal laws result from the simplest axioms of a complete deductive system [Ramsey]