Combining Texts

All the ideas for 'Isagoge ('Introduction')', 'Which Logic is the Right Logic?' and 'The Meaning of 'Meaning''

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26 ideas

4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / j. Axiom of Choice IX
10775 The axiom of choice now seems acceptable and obvious (if it is meaningful) [Tharp]
5. Theory of Logic / A. Overview of Logic / 1. Overview of Logic
10766 Logic is either for demonstration, or for characterizing structures [Tharp]
5. Theory of Logic / A. Overview of Logic / 5. First-Order Logic
10767 Elementary logic is complete, but cannot capture mathematics [Tharp]
5. Theory of Logic / A. Overview of Logic / 7. Second-Order Logic
10769 Second-order logic isn't provable, but will express set-theory and classic problems [Tharp]
5. Theory of Logic / E. Structures of Logic / 2. Logical Connectives / b. Basic connectives
10762 In sentential logic there is a simple proof that all truth functions can be reduced to 'not' and 'and' [Tharp]
5. Theory of Logic / G. Quantification / 2. Domain of Quantification
10776 The main quantifiers extend 'and' and 'or' to infinite domains [Tharp]
5. Theory of Logic / G. Quantification / 7. Unorthodox Quantification
10774 There are at least five unorthodox quantifiers that could be used [Tharp]
5. Theory of Logic / J. Model Theory in Logic / 3. Löwenheim-Skolem Theorems
10773 The Löwenheim-Skolem property is a limitation (e.g. can't say there are uncountably many reals) [Tharp]
10777 Skolem mistakenly inferred that Cantor's conceptions were illusory [Tharp]
5. Theory of Logic / K. Features of Logics / 3. Soundness
10765 Soundness would seem to be an essential requirement of a proof procedure [Tharp]
5. Theory of Logic / K. Features of Logics / 4. Completeness
10763 Completeness and compactness together give axiomatizability [Tharp]
5. Theory of Logic / K. Features of Logics / 5. Incompleteness
10770 If completeness fails there is no algorithm to list the valid formulas [Tharp]
5. Theory of Logic / K. Features of Logics / 6. Compactness
10771 Compactness is important for major theories which have infinitely many axioms [Tharp]
10772 Compactness blocks infinite expansion, and admits non-standard models [Tharp]
5. Theory of Logic / K. Features of Logics / 8. Enumerability
10764 A complete logic has an effective enumeration of the valid formulas [Tharp]
10768 Effective enumeration might be proved but not specified, so it won't guarantee knowledge [Tharp]
8. Modes of Existence / D. Universals / 1. Universals
15034 Are genera and species real or conceptual? bodies or incorporeal? in sensibles or separate from them? [Porphyry]
9. Objects / D. Essence of Objects / 15. Against Essentialism
18890 Putnam smuggles essentialism about liquids into his proof that water must be H2O [Salmon,N on Putnam]
15. Nature of Minds / B. Features of Minds / 5. Qualia / b. Qualia and intentionality
7705 The Twin Earth theory suggests that intentionality is independent of qualia [Jacquette on Putnam]
18. Thought / C. Content / 5. Twin Earth
4099 If Twins talking about 'water' and 'XYZ' have different thoughts but identical heads, then thoughts aren't in the head [Putnam, by Crane]
12026 We say ice and steam are different forms of water, but not that they are different forms of H2O [Forbes,G on Putnam]
3208 Does 'water' mean a particular substance that was 'dubbed'? [Putnam, by Rey]
19. Language / B. Reference / 4. Descriptive Reference / a. Sense and reference
3893 Often reference determines sense, and not (as Frege thought) vice versa [Putnam, by Scruton]
26. Natural Theory / B. Natural Kinds / 4. Source of Kinds
11191 The hidden structure of a natural kind determines membership in all possible worlds [Putnam]
26. Natural Theory / D. Laws of Nature / 8. Scientific Essentialism / a. Scientific essentialism
11192 If causes are the essence of diseases, then disease is an example of a relational essence [Putnam, by Williams,NE]
11190 Archimedes meant by 'gold' the hidden structure or essence of the stuff [Putnam]