Combining Texts

All the ideas for 'works', 'Introduction to the Philosophy of Mathematics' and 'Word and Object'

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51 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]
4. Formal Logic / E. Nonclassical Logics / 2. Intuitionist Logic
Rejecting double negation elimination undermines reductio proofs [Colyvan]
Showing a disproof is impossible is not a proof, so don't eliminate double negation [Colyvan]
5. Theory of Logic / D. Assumptions for Logic / 2. Excluded Middle
Excluded middle says P or not-P; bivalence says P is either true or false [Colyvan]
5. Theory of Logic / G. Quantification / 2. Domain of Quantification
De Morgan introduced a 'universe of discourse', to replace Boole's universe of 'all things' [De Morgan, by Walicki]
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
Löwenheim proved his result for a first-order sentence, and Skolem generalised it [Colyvan]
5. Theory of Logic / K. Features of Logics / 1. Axiomatisation
Axioms are 'categorical' if all of their models are isomorphic [Colyvan]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / e. Ordinal numbers
Ordinal numbers represent order relations [Colyvan]
Any progression will do nicely for numbers; they can all then be used to measure multiplicity [Quine]
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / a. The Infinite
Intuitionists only accept a few safe infinities [Colyvan]
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / j. Infinite divisibility
Infinitesimals were sometimes zero, and sometimes close to zero [Colyvan]
6. Mathematics / B. Foundations for Mathematics / 1. Foundations for Mathematics
Reducing real numbers to rationals suggested arithmetic as the foundation of maths [Colyvan]
6. Mathematics / B. Foundations for Mathematics / 4. Axioms for Number / f. Mathematical induction
Transfinite induction moves from all cases, up to the limit ordinal [Colyvan]
6. Mathematics / B. Foundations for Mathematics / 6. Mathematics as Set Theory / a. Mathematics is set theory
Most mathematical proofs are using set theory, but without saying so [Colyvan]
6. Mathematics / B. Foundations for Mathematics / 7. Mathematical Structuralism / a. Structuralism
Structuralism say only 'up to isomorphism' matters because that is all there is to it [Colyvan]
6. Mathematics / B. Foundations for Mathematics / 7. Mathematical Structuralism / e. Structuralism critique
If 'in re' structures relies on the world, does the world contain rich enough structures? [Colyvan]
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
Physical objects in space-time are just events or processes, no matter how disconnected [Quine]
The notion of a physical object is by far the most useful one for science [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]
What stays the same in assessing a counterfactual antecedent depends on context [Quine]
Counterfactuals have no place in a strict account of science [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]
14. Science / C. Induction / 6. Bayes's Theorem
Probability supports Bayesianism better as degrees of belief than as ratios of frequencies [Colyvan]
14. Science / D. Explanation / 2. Types of Explanation / e. Lawlike explanations
Mathematics can reveal structural similarities in diverse systems [Colyvan]
14. Science / D. Explanation / 2. Types of Explanation / f. Necessity in explanations
Mathematics can show why some surprising events have to occur [Colyvan]
14. Science / D. Explanation / 2. Types of Explanation / m. Explanation by proof
Proof by cases (by 'exhaustion') is said to be unexplanatory [Colyvan]
Reductio proofs do not seem to be very explanatory [Colyvan]
If inductive proofs hold because of the structure of natural numbers, they may explain theorems [Colyvan]
Can a proof that no one understands (of the four-colour theorem) really be a proof? [Colyvan]
15. Nature of Minds / C. Capacities of Minds / 5. Generalisation by mind
Mathematical generalisation is by extending a system, or by abstracting away from it [Colyvan]
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]