Combining Texts

All the ideas for 'Identity and Spatio-Temporal Continuity', 'Believing the Axioms I' and 'Philosophy of Logic'

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26 ideas

3. Truth / F. Semantic Truth / 1. Tarski's Truth / a. Tarski's truth definition
18951 For scientific purposes there is a precise concept of 'true-in-L', using set theory [Putnam]
4. Formal Logic / A. Syllogistic Logic / 1. Aristotelian Logic
18953 Modern notation frees us from Aristotle's restriction of only using two class-names in premises [Putnam]
4. Formal Logic / A. Syllogistic Logic / 2. Syllogistic Logic
18949 The universal syllogism is now expressed as the transitivity of subclasses [Putnam]
4. Formal Logic / C. Predicate Calculus PC / 2. Tools of Predicate Calculus / a. Symbols of PC
18952 '⊃' ('if...then') is used with the definition 'Px ⊃ Qx' is short for '¬(Px & ¬Qx)' [Putnam]
4. Formal Logic / F. Set Theory ST / 3. Types of Set / a. Types of set
18958 In type theory, 'x ∈ y' is well defined only if x and y are of the appropriate type [Putnam]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / a. Axioms for sets
13011 New axioms are being sought, to determine the size of the continuum [Maddy]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / b. Axiom of Extensionality I
13013 The Axiom of Extensionality seems to be analytic [Maddy]
13014 Extensional sets are clearer, simpler, unique and expressive [Maddy]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / f. Axiom of Infinity V
13021 The Axiom of Infinity states Cantor's breakthrough that launched modern mathematics [Maddy]
13022 Infinite sets are essential for giving an account of the real numbers [Maddy]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / g. Axiom of Powers VI
13023 The Power Set Axiom is needed for, and supported by, accounts of the continuum [Maddy]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / j. Axiom of Choice IX
13024 Efforts to prove the Axiom of Choice have failed [Maddy]
13025 Modern views say the Choice set exists, even if it can't be constructed [Maddy]
13026 A large array of theorems depend on the Axiom of Choice [Maddy]
4. Formal Logic / F. Set Theory ST / 5. Conceptions of Set / e. Iterative sets
13019 The Iterative Conception says everything appears at a stage, derived from the preceding appearances [Maddy]
4. Formal Logic / F. Set Theory ST / 5. Conceptions of Set / f. Limitation of Size
13018 Limitation of Size is a vague intuition that over-large sets may generate paradoxes [Maddy]
5. Theory of Logic / A. Overview of Logic / 2. History of Logic
18954 Before the late 19th century logic was trivialised by not dealing with relations [Putnam]
5. Theory of Logic / A. Overview of Logic / 5. First-Order Logic
18956 Asserting first-order validity implicitly involves second-order reference to classes [Putnam]
5. Theory of Logic / C. Ontology of Logic / 1. Ontology of Logic
18962 Unfashionably, I think logic has an empirical foundation [Putnam]
5. Theory of Logic / E. Structures of Logic / 5. Functions in Logic
18961 We can identify functions with certain sets - or identify sets with certain functions [Putnam]
5. Theory of Logic / I. Semantics of Logic / 3. Logical Truth
18955 Having a valid form doesn't ensure truth, as it may be meaningless [Putnam]
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / f. Uncountable infinities
18959 Sets larger than the continuum should be studied in an 'if-then' spirit [Putnam]
8. Modes of Existence / E. Nominalism / 1. Nominalism / a. Nominalism
18957 Nominalism only makes sense if it is materialist [Putnam]
9. Objects / A. Existence of Objects / 2. Abstract Objects / b. Need for abstracta
18950 Physics is full of non-physical entities, such as space-vectors [Putnam]
9. Objects / A. Existence of Objects / 5. Individuation / e. Individuation by kind
13128 'Ultimate sortals' cannot explain ontological categories [Westerhoff on Wiggins]
14. Science / A. Basis of Science / 4. Prediction
18960 Most predictions are uninteresting, and are only sought in order to confirm a theory [Putnam]