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All the ideas for 'Intro to Naming,Necessity and Natural Kinds', 'On the Concept of Number' and 'What is Logic?'

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16 ideas

2. Reason / D. Definition / 1. Definitions
The new view is that "water" is a name, and has no definition [Schwartz,SP]
2. Reason / D. Definition / 3. Types of Definition
A decent modern definition should always imply a semantics [Hacking]
4. Formal Logic / B. Propositional Logic PL / 2. Tools of Propositional Logic / d. Basic theorems of PL
Gentzen's Cut Rule (or transitivity of deduction) is 'If A |- B and B |- C, then A |- C' [Hacking]
Only Cut reduces complexity, so logic is constructive without it, and it can be dispensed with [Hacking]
'Thinning' ('dilution') is the key difference between deduction (which allows it) and induction [Hacking]
5. Theory of Logic / A. Overview of Logic / 4. Pure Logic
The various logics are abstractions made from terms like 'if...then' in English [Hacking]
5. Theory of Logic / A. Overview of Logic / 5. First-Order Logic
First-order logic is the strongest complete compact theory with Löwenheim-Skolem [Hacking]
A limitation of first-order logic is that it cannot handle branching quantifiers [Hacking]
5. Theory of Logic / A. Overview of Logic / 7. Second-Order Logic
Second-order completeness seems to need intensional entities and possible worlds [Hacking]
5. Theory of Logic / E. Structures of Logic / 2. Logical Connectives / a. Logical connectives
With a pure notion of truth and consequence, the meanings of connectives are fixed syntactically [Hacking]
5. Theory of Logic / E. Structures of Logic / 4. Variables in Logic
Perhaps variables could be dispensed with, by arrows joining places in the scope of quantifiers [Hacking]
5. Theory of Logic / F. Referring in Logic / 1. Naming / b. Names as descriptive
We refer to Thales successfully by name, even if all descriptions of him are false [Schwartz,SP]
The traditional theory of names says some of the descriptions must be correct [Schwartz,SP]
5. Theory of Logic / J. Model Theory in Logic / 3. Löwenheim-Skolem Theorems
If it is a logic, the Löwenheim-Skolem theorem holds for it [Hacking]
6. Mathematics / C. Sources of Mathematics / 7. Formalism
Hilbert said (to block paradoxes) that mathematical existence is entailed by consistency [Hilbert, by Potter]
18. Thought / C. Content / 8. Intension
The intension of "lemon" is the conjunction of properties associated with it [Schwartz,SP]