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All the ideas for 'What is Logic?st1=Ian Hacking', 'The Nature of Thought' and 'Word and Object'

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42 ideas

1. Philosophy / E. Nature of Metaphysics / 4. Metaphysics as Science
Quine's naturalistic and empirical view is based entirely on first-order logic and set theory [Quine, by Mautner]
1. Philosophy / E. Nature of Metaphysics / 6. Metaphysics as Conceptual
Enquiry needs a conceptual scheme, so we should retain the best available [Quine]
2. Reason / A. Nature of Reason / 6. Coherence
Full coherence might involve consistency and mutual entailment of all propositions [Blanshard, by Dancy,J]
2. Reason / D. Definition / 3. Types of Definition
A decent modern definition should always imply a semantics [Hacking]
3. Truth / D. Coherence Truth / 1. Coherence Truth
Coherence tests for truth without implying correspondence, so truth is not correspondence [Blanshard, by Young,JO]
4. Formal Logic / B. Propositional Logic PL / 2. Tools of Propositional Logic / d. Basic theorems of PL
Gentzen's Cut Rule (or transitivity of deduction) is 'If A |- B and B |- C, then A |- C' [Hacking]
Only Cut reduces complexity, so logic is constructive without it, and it can be dispensed with [Hacking]
'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
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
First-order logic is the strongest complete compact theory with Löwenheim-Skolem [Hacking]
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
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
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
Perhaps variables could be dispensed with, by arrows joining places in the scope of quantifiers [Hacking]
5. Theory of Logic / G. Quantification / 6. Plural Quantification
Plurals can in principle be paraphrased away altogether [Quine]
5. Theory of Logic / J. Model Theory in Logic / 3. Löwenheim-Skolem Theorems
If it is a logic, the Löwenheim-Skolem theorem holds for it [Hacking]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / e. Ordinal numbers
Any progression will do nicely for numbers; they can all then be used to measure multiplicity [Quine]
6. Mathematics / C. Sources of Mathematics / 4. Mathematical Empiricism / b. Indispensability of mathematics
Nearly all of mathematics has to quantify over abstract objects [Quine]
7. Existence / E. Categories / 4. Category Realism
The quest for ultimate categories is the quest for a simple clear pattern of notation [Quine]
8. Modes of Existence / C. Powers and Dispositions / 6. Dispositions / a. Dispositions
Either dispositions rest on structures, or we keep saying 'all things being equal' [Quine]
8. Modes of Existence / C. Powers and Dispositions / 6. Dispositions / d. Dispositions as occurrent
Explain unmanifested dispositions as structural similarities to objects which have manifested them [Quine, by Martin,CB]
8. Modes of Existence / E. Nominalism / 5. Class Nominalism
Quine aims to deal with properties by the use of eternal open sentences, or classes [Quine, by Devitt]
9. Objects / A. Existence of Objects / 1. Physical Objects
The notion of a physical object is by far the most useful one for science [Quine]
Physical objects in space-time are just events or processes, no matter how disconnected [Quine]
9. Objects / D. Essence of Objects / 15. Against Essentialism
Mathematicians must be rational but not two-legged, cyclists the opposite. So a mathematical cyclist? [Quine]
Cyclist are not actually essentially two-legged [Brody on Quine]
9. Objects / F. Identity among Objects / 2. Defining Identity
We can paraphrase 'x=y' as a sequence of the form 'if Fx then Fy' [Quine]
10. Modality / B. Possibility / 8. Conditionals / c. Truth-function conditionals
Normal conditionals have a truth-value gap when the antecedent is false. [Quine]
10. Modality / B. Possibility / 8. Conditionals / e. Supposition conditionals
Conditionals are pointless if the truth value of the antecedent is known [Quine]
10. Modality / B. Possibility / 9. Counterfactuals
We feign belief in counterfactual antecedents, and assess how convincing the consequent is [Quine]
Counterfactuals are plausible when dispositions are involved, as they imply structures [Quine]
Counterfactuals have no place in a strict account of science [Quine]
What stays the same in assessing a counterfactual antecedent depends on context [Quine]
14. Science / B. Scientific Theories / 1. Scientific Theory
Two theories can be internally consistent and match all the facts, yet be inconsistent with one another [Quine, by Baggini /Fosl]
17. Mind and Body / E. Mind as Physical / 3. Eliminativism
Quine expresses the instrumental version of eliminativism [Quine, by Rey]
19. Language / F. Communication / 6. Interpreting Language / b. Indeterminate translation
Indeterminacy of translation also implies indeterminacy in interpreting people's mental states [Dennett on Quine]
The firmer the links between sentences and stimuli, the less translations can diverge [Quine]
We can never precisely pin down how to translate the native word 'Gavagai' [Quine]
Stimulus synonymy of 'Gavagai' and 'Rabbit' does not even guarantee they are coextensive [Quine]
Dispositions to speech behaviour, and actual speech, are never enough to fix any one translation [Quine]
19. Language / F. Communication / 6. Interpreting Language / c. Principle of charity
We should be suspicious of a translation which implies that a people have very strange beliefs [Quine]
Weird translations are always possible, but they improve if we impose our own logic on them [Quine]