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All the ideas for 'What is Logic?st1=Ian Hacking', 'Why Propositions Aren't Truth-Supporting Circumstance' and 'Causal Structuralism'

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21 ideas

2. Reason / D. Definition / 3. Types of Definition
13838 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
13833 'Thinning' ('dilution') is the key difference between deduction (which allows it) and induction [Hacking]
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]
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]
8. Modes of Existence / C. Powers and Dispositions / 2. Powers as Basic
15127 A categorical basis could hardly explain a disposition if it had no powers of its own [Hawthorne]
8. Modes of Existence / C. Powers and Dispositions / 5. Powers and Properties
15123 Is the causal profile of a property its essence? [Hawthorne]
15122 Could two different properties have the same causal profile? [Hawthorne]
15124 If properties are more than their powers, we could have two properties with the same power [Hawthorne]
9. Objects / C. Structure of Objects / 2. Hylomorphism / b. Form as principle
15128 We can treat the structure/form of the world differently from the nodes/matter of the world [Hawthorne]
9. Objects / D. Essence of Objects / 3. Individual Essences
15121 An individual essence is a necessary and sufficient profile for a thing [Hawthorne]
19. Language / C. Assigning Meanings / 2. Semantics
13965 Semantics as theory of meaning and semantics as truth-based logical consequence are very different [Soames]
19. Language / C. Assigning Meanings / 6. Truth-Conditions Semantics
13964 Semantic content is a proposition made of sentence constituents (not some set of circumstances) [Soames]
26. Natural Theory / C. Causation / 7. Eliminating causation
15126 Maybe scientific causation is just generalisation about the patterns [Hawthorne]
26. Natural Theory / D. Laws of Nature / 6. Laws as Numerical
15125 We only know the mathematical laws, but not much else [Hawthorne]