Combining Texts

All the ideas for 'Letters to Russell', 'Words without Objects' and 'On Second-Order Logic'

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20 ideas

5. Theory of Logic / A. Overview of Logic / 7. Second-Order Logic
14249 Boolos reinterprets second-order logic as plural logic [Boolos, by Oliver/Smiley]
10830 Second-order logic metatheory is set-theoretic, and second-order validity has set-theoretic problems [Boolos]
5. Theory of Logic / C. Ontology of Logic / 1. Ontology of Logic
10829 A sentence can't be a truth of logic if it asserts the existence of certain sets [Boolos]
5. Theory of Logic / E. Structures of Logic / 4. Variables in Logic
12797 If plural variables have 'some values', then non-count variables have 'some value' [Laycock]
5. Theory of Logic / G. Quantification / 2. Domain of Quantification
10832 '∀x x=x' only means 'everything is identical to itself' if the range of 'everything' is fixed [Boolos]
5. Theory of Logic / G. Quantification / 6. Plural Quantification
12794 Plurals are semantical but not ontological [Laycock]
5. Theory of Logic / K. Features of Logics / 4. Completeness
10834 Weak completeness: if it is valid, it is provable. Strong: it is provable from a set of sentences [Boolos]
5. Theory of Logic / K. Features of Logics / 6. Compactness
13841 Why should compactness be definitive of logic? [Boolos, by Hacking]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / g. Real numbers
18253 I wish to go straight from cardinals to reals (as ratios), leaving out the rationals [Frege]
6. Mathematics / A. Nature of Mathematics / 4. Using Numbers / c. Counting procedure
17694 Some non-count nouns can be used for counting, as in 'several wines' or 'fewer cheeses' [Laycock]
17695 Some apparent non-count words can take plural forms, such as 'snows' or 'waters' [Laycock]
6. Mathematics / B. Foundations for Mathematics / 4. Axioms for Number / e. Peano arithmetic 2nd-order
10833 Many concepts can only be expressed by second-order logic [Boolos]
6. Mathematics / C. Sources of Mathematics / 6. Logicism / a. Early logicism
18166 The loss of my Rule V seems to make foundations for arithmetic impossible [Frege]
7. Existence / C. Structure of Existence / 8. Stuff / a. Pure stuff
12792 The category of stuff does not suit reference [Laycock]
12799 Descriptions of stuff are neither singular aggregates nor plural collections [Laycock]
7. Existence / C. Structure of Existence / 8. Stuff / b. Mixtures
12818 We shouldn't think some water retains its identity when it is mixed with air [Laycock]
9. Objects / A. Existence of Objects / 2. Abstract Objects / c. Modern abstracta
18269 Logical objects are extensions of concepts, or ranges of values of functions [Frege]
9. Objects / C. Structure of Objects / 8. Parts of Objects / a. Parts of objects
12795 Parts must be of the same very general type as the wholes [Laycock]
15. Nature of Minds / C. Capacities of Minds / 5. Generalisation by mind
17696 'Humility is a virtue' has an abstract noun, but 'water is a liquid' has a generic concrete noun [Laycock]
19. Language / B. Reference / 1. Reference theories
12791 It is said that proper reference is our intellectual link with the world [Laycock]