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All the ideas for 'What is Logic?st1=Ian Hacking', 'The Great Event' and 'Causation and Laws of Nature'

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20 ideas

1. Philosophy / F. Analytic Philosophy / 3. Analysis of Preconditions
14600 Analysis aims at secure necessary and sufficient conditions [Schaffer,J]
2. Reason / D. Definition / 3. Types of Definition
13838 A decent modern definition should always imply a semantics [Hacking]
2. Reason / F. Fallacies / 1. Fallacy
14603 'Reification' occurs if we mistake a concept for a thing [Schaffer,J]
4. Formal Logic / B. Propositional Logic PL / 2. Tools of Propositional Logic / d. Basic theorems of PL
13834 Gentzen's Cut Rule (or transitivity of deduction) is 'If A |- B and B |- C, then A |- C' [Hacking]
13835 Only Cut reduces complexity, so logic is constructive without it, and it can be dispensed with [Hacking]
13833 'Thinning' ('dilution') is the key difference between deduction (which allows it) and induction [Hacking]
4. Formal Logic / D. Modal Logic ML / 3. Modal Logic Systems / d. System T
14607 T adds □p→p for reflexivity, and is ideal for modeling lawhood [Schaffer,J]
5. Theory of Logic / A. Overview of Logic / 4. Pure Logic
13845 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
13840 First-order logic is the strongest complete compact theory with Löwenheim-Skolem [Hacking]
13844 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
13842 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
13837 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
13839 Perhaps variables could be dispensed with, by arrows joining places in the scope of quantifiers [Hacking]
5. Theory of Logic / J. Model Theory in Logic / 3. Löwenheim-Skolem Theorems
13843 If it is a logic, the Löwenheim-Skolem theorem holds for it [Hacking]
6. Mathematics / C. Sources of Mathematics / 4. Mathematical Empiricism / b. Indispensability of mathematics
14604 If a notion is ontologically basic, it should be needed in our best attempt at science [Schaffer,J]
7. Existence / C. Structure of Existence / 2. Reduction
14599 Three types of reduction: Theoretical (of terms), Definitional (of concepts), Ontological (of reality) [Schaffer,J]
8. Modes of Existence / B. Properties / 13. Tropes / a. Nature of tropes
14605 Tropes are the same as events [Schaffer,J]
9. Objects / A. Existence of Objects / 5. Individuation / a. Individuation
14601 Individuation aims to count entities, by saying when there is one [Schaffer,J]
10. Modality / D. Knowledge of Modality / 4. Conceivable as Possible / a. Conceivable as possible
14606 Only ideal conceivability could indicate what is possible [Schaffer,J]
28. God / B. Proving God / 3. Proofs of Evidence / e. Miracles
7902 The Buddha made flowers float in the air, to impress people, and make them listen [Mahavastu]