Combining Texts

All the ideas for 'General Facts,Phys Necessity, and Metaph of Time', 'Word and Object' and 'Introduction to Mathematical Logic'

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49 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]
3. Truth / B. Truthmakers / 3. Truthmaker Maximalism
The truth-maker principle is that every truth has a sufficient truth-maker [Forrest]
4. Formal Logic / B. Propositional Logic PL / 1. Propositional Logic
Post proved the consistency of propositional logic in 1921 [Walicki]
Propositional language can only relate statements as the same or as different [Walicki]
4. Formal Logic / B. Propositional Logic PL / 3. Truth Tables
Boolean connectives are interpreted as functions on the set {1,0} [Walicki]
4. Formal Logic / F. Set Theory ST / 3. Types of Set / b. Empty (Null) Set
The empty set is useful for defining sets by properties, when the members are not yet known [Walicki]
The empty set avoids having to take special precautions in case members vanish [Walicki]
4. Formal Logic / F. Set Theory ST / 6. Ordering in Sets
Ordinals play the central role in set theory, providing the model of well-ordering [Walicki]
5. Theory of Logic / A. Overview of Logic / 1. Overview of Logic
To determine the patterns in logic, one must identify its 'building blocks' [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 / 1. Logical Models
A 'model' of a theory specifies interpreting a language in a domain to make all theorems true [Walicki]
5. Theory of Logic / J. Model Theory in Logic / 3. Löwenheim-Skolem Theorems
The L-S Theorem says no theory (even of reals) says more than a natural number theory [Walicki]
5. Theory of Logic / K. Features of Logics / 1. Axiomatisation
Axiomatic systems are purely syntactic, and do not presuppose any interpretation [Walicki]
A compact axiomatisation makes it possible to understand a field as a whole [Walicki]
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]
Members of ordinals are ordinals, and also subsets of ordinals [Walicki]
Ordinals are transitive sets of transitive sets; or transitive sets totally ordered by inclusion [Walicki]
Ordinals are the empty set, union with the singleton, and any arbitrary union of ordinals [Walicki]
The union of finite ordinals is the first 'limit ordinal'; 2ω is the second... [Walicki]
Two infinite ordinals can represent a single infinite cardinal [Walicki]
6. Mathematics / B. Foundations for Mathematics / 3. Axioms for Geometry
In non-Euclidean geometry, all Euclidean theorems are valid that avoid the fifth postulate [Walicki]
6. Mathematics / B. Foundations for Mathematics / 4. Axioms for Number / f. Mathematical induction
Inductive proof depends on the choice of the ordering [Walicki]
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 / A. Necessity / 2. Nature of Necessity
Scotus based modality on semantic consistency, instead of on what the future could allow [Walicki]
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]