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All the ideas for 'What is Logic?st1=Ian Hacking', 'Causation' and 'Meaning and Reference'

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20 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]
10. Modality / D. Knowledge of Modality / 1. A Priori Necessary
9169 A statement can be metaphysically necessary and epistemologically contingent [Putnam]
10. Modality / D. Knowledge of Modality / 4. Conceivable as Possible / a. Conceivable as possible
5819 Conceivability is no proof of possibility [Putnam]
14. Science / D. Explanation / 2. Types of Explanation / g. Causal explanations
8406 Not all explanations are causal, but if a thing can be explained at all, it can be explained causally [Sanford]
18. Thought / C. Content / 6. Broad Content
9168 I can't distinguish elm trees, but I mean by 'elm' the same set of trees as everybody else [Putnam]
5820 'Water' has an unnoticed indexical component, referring to stuff around here [Putnam]
19. Language / B. Reference / 3. Direct Reference / c. Social reference
9170 We need to recognise the contribution of society and of the world in determining reference [Putnam]
19. Language / F. Communication / 4. Private Language
5817 Language is more like a cooperative steamship than an individual hammer [Putnam]
26. Natural Theory / C. Causation / 8. Particular Causation / c. Conditions of causation
8407 A totality of conditions necessary for an occurrence is usually held to be jointly sufficient for it [Sanford]
26. Natural Theory / D. Laws of Nature / 8. Scientific Essentialism / b. Scientific necessity
5818 If water is H2O in the actual world, there is no possible world where it isn't H2O [Putnam]