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All the ideas for 'What is Logic?st1=Ian Hacking', 'Sociobiology' and 'Metaphysical Dependence'

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22 ideas

1. Philosophy / F. Analytic Philosophy / 5. Linguistic Analysis
14092 Philosophers are often too fussy about words, dismissing perfectly useful ordinary terms [Rosen]
2. Reason / D. Definition / 1. Definitions
14100 Figuring in the definition of a thing doesn't make it a part of that thing [Rosen]
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]
5. Theory of Logic / K. Features of Logics / 10. Monotonicity
14096 Explanations fail to be monotonic [Rosen]
7. Existence / C. Structure of Existence / 1. Grounding / a. Nature of grounding
14097 Things could be true 'in virtue of' others as relations between truths, or between truths and items [Rosen]
7. Existence / D. Theories of Reality / 8. Facts / a. Facts
14095 Facts are structures of worldly items, rather like sentences, individuated by their ingredients [Rosen]
8. Modes of Existence / B. Properties / 4. Intrinsic Properties
14093 An 'intrinsic' property is one that depends on a thing and its parts, and not on its relations [Rosen]
10. Modality / A. Necessity / 5. Metaphysical Necessity
14094 The excellent notion of metaphysical 'necessity' cannot be defined [Rosen]
10. Modality / C. Sources of Modality / 1. Sources of Necessity
14101 Are necessary truths rooted in essences, or also in basic grounding laws? [Rosen]
19. Language / E. Analyticity / 1. Analytic Propositions
14099 'Bachelor' consists in or reduces to 'unmarried' male, but not the other way around [Rosen]
22. Metaethics / A. Ethics Foundations / 2. Source of Ethics / d. Biological ethics
22187 Genetic behaviours that have enhanced human success include aggression, rape and xenophobia [Wilson,EO, by Okasha]
27. Natural Reality / F. Chemistry / 1. Chemistry
14098 An acid is just a proton donor [Rosen]