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All the ideas for 'What is Logic?st1=Ian Hacking', 'On Sensations (frags)' and 'Epistemology Naturalized'

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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
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]
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 / 6. Logicism / d. Logicism critique
1635 Mathematics reduces to set theory (which is a bit vague and unobvious), but not to logic proper [Quine]
13. Knowledge Criteria / C. External Justification / 9. Naturalised Epistemology
7627 You can't reduce epistemology to psychology, because that presupposes epistemology [Maund on Quine]
8871 We should abandon a search for justification or foundations, and focus on how knowledge is acquired [Quine, by Davidson]
8826 If we abandon justification and normativity in epistemology, we must also abandon knowledge [Kim on Quine]
8827 Without normativity, naturalized epistemology isn't even about beliefs [Kim on Quine]
8899 Epistemology is a part of psychology, studying how our theories relate to our evidence [Quine]
13. Knowledge Criteria / E. Relativism / 3. Subjectivism
2975 That honey is sweet I do not affirm, but I agree that it appears so [Timon]
19. Language / A. Nature of Meaning / 1. Meaning
8898 Inculcations of meanings of words rests ultimately on sensory evidence [Quine]
19. Language / E. Analyticity / 4. Analytic/Synthetic Critique
8900 In observation sentences, we could substitute community acceptance for analyticity [Quine]