Combining Texts

All the ideas for 'Set Theory', 'Concepts:where cogn.science went wrong' and 'Frege's Theory of Numbers'

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24 ideas

2. Reason / D. Definition / 13. Against Definition
We have no successful definitions, because they all use indefinable words [Fodor]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / b. Axiom of Extensionality I
Extensionality: ∀x ∀y (∀z (z ∈ x ↔ z ∈ y) → x = y) [Kunen]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / c. Axiom of Pairing II
Pairing: ∀x ∀y ∃z (x ∈ z ∧ y ∈ z) [Kunen]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / d. Axiom of Unions III
Union: ∀F ∃A ∀Y ∀x (x ∈ Y ∧ Y ∈ F → x ∈ A) [Kunen]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / f. Axiom of Infinity V
Infinity: ∃x (0 ∈ x ∧ ∀y ∈ x (S(y) ∈ x) [Kunen]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / g. Axiom of Powers VI
Power Set: ∀x ∃y ∀z(z ⊂ x → z ∈ y) [Kunen]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / h. Axiom of Replacement VII
Replacement: ∀x∈A ∃!y φ(x,y) → ∃Y ∀X∈A ∃y∈Y φ(x,y) [Kunen]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / i. Axiom of Foundation VIII
Foundation:∀x(∃y(y∈x) → ∃y(y∈x ∧ ¬∃z(z∈x ∧ z∈y))) [Kunen]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / j. Axiom of Choice IX
Choice: ∀A ∃R (R well-orders A) [Kunen]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / k. Axiom of Existence
Set Existence: ∃x (x = x) [Kunen]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / n. Axiom of Comprehension
Comprehension: ∃y ∀x (x ∈ y ↔ x ∈ z ∧ φ) [Kunen]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / o. Axiom of Constructibility V = L
Constructibility: V = L (all sets are constructible) [Kunen]
6. Mathematics / A. Nature of Mathematics / 4. Using Numbers / c. Counting procedure
Parsons says counting is tagging as first, second, third..., and converting the last to a cardinal [Parsons,C, by Heck]
7. Existence / A. Nature of Existence / 2. Types of Existence
If 'exist' is ambiguous in 'chairs and numbers exist', that mirrors the difference between chairs and numbers [Fodor]
8. Modes of Existence / C. Powers and Dispositions / 6. Dispositions / c. Dispositions as conditional
Empiricists use dispositions reductively, as 'possibility of sensation' or 'possibility of experimental result' [Fodor]
12. Knowledge Sources / D. Empiricism / 2. Associationism
Associationism can't explain how truth is preserved [Fodor]
18. Thought / C. Content / 2. Ideas
Mental representations are the old 'Ideas', but without images [Fodor]
18. Thought / D. Concepts / 2. Origin of Concepts / c. Nativist concepts
Fodor is now less keen on the innateness of concepts [Fodor, by Lowe]
18. Thought / D. Concepts / 3. Ontology of Concepts / a. Concepts as representations
It is essential to the concept CAT that it be satisfied by cats [Fodor]
18. Thought / D. Concepts / 3. Ontology of Concepts / b. Concepts as abilities
I prefer psychological atomism - that concepts are independent of epistemic capacities [Fodor]
18. Thought / D. Concepts / 4. Structure of Concepts / b. Analysis of concepts
Definable concepts have constituents, which are necessary, individuate them, and demonstrate possession [Fodor]
18. Thought / D. Concepts / 4. Structure of Concepts / d. Concepts as prototypes
Many concepts lack prototypes, and complex prototypes aren't built from simple ones [Fodor]
18. Thought / D. Concepts / 4. Structure of Concepts / f. Theory theory of concepts
The theory theory can't actually tell us what concepts are [Fodor]
19. Language / C. Assigning Meanings / 2. Semantics
English has no semantic theory, just associations between sentences and thoughts [Fodor]