Combining Texts

All the ideas for 'Set Theory', 'In Defense of Absolute Essentialism' and 'Intensions Revisited'

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24 ideas

4. Formal Logic / D. Modal Logic ML / 1. Modal Logic
Quantified modal logic collapses if essence is withdrawn [Quine]
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]
9. Objects / D. Essence of Objects / 6. Essence as Unifier
A property is essential iff the object would not exist if it lacked that property [Forbes,G]
Properties are trivially essential if they are not grounded in a thing's specific nature [Forbes,G]
9. Objects / D. Essence of Objects / 7. Essence and Necessity / a. Essence as necessary properties
A relation is essential to two items if it holds in every world where they exist [Forbes,G]
9. Objects / D. Essence of Objects / 7. Essence and Necessity / c. Essentials are necessary
Trivially essential properties are existence, self-identity, and de dicto necessities [Forbes,G]
9. Objects / D. Essence of Objects / 9. Essence and Properties
A property is 'extraneously essential' if it is had only because of the properties of other objects [Forbes,G]
9. Objects / D. Essence of Objects / 11. Essence of Artefacts
One might be essentialist about the original bronze from which a statue was made [Forbes,G]
9. Objects / D. Essence of Objects / 15. Against Essentialism
Essences can make sense in a particular context or enquiry, as the most basic predicates [Quine]
10. Modality / A. Necessity / 11. Denial of Necessity
Necessity is relative to context; it is what is assumed in an inquiry [Quine]
10. Modality / C. Sources of Modality / 4. Necessity from Concepts
The source of de dicto necessity is not concepts, but the actual properties of the thing [Forbes,G]
10. Modality / E. Possible worlds / 1. Possible Worlds / e. Against possible worlds
Possible worlds are a way to dramatise essentialism, and yet they presuppose essentialism [Quine]
10. Modality / E. Possible worlds / 3. Transworld Objects / b. Rigid designation
A rigid designator (for all possible worlds) picks out an object by its essential traits [Quine]
11. Knowledge Aims / A. Knowledge / 4. Belief / a. Beliefs
Beliefs can be ascribed to machines [Quine]