Combining Texts

All the ideas for 'Lectures on Ethics', 'The Identity of Indiscernibles' and 'Model Theory'

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13 ideas

2. Reason / D. Definition / 7. Contextual Definition
10476 The idea that groups of concepts could be 'implicitly defined' was abandoned [Hodges,W]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / j. Axiom of Choice IX
10196 The Axiom of Choice needs a criterion of choice [Black]
5. Theory of Logic / A. Overview of Logic / 5. First-Order Logic
10478 Since first-order languages are complete, |= and |- have the same meaning [Hodges,W]
5. Theory of Logic / B. Logical Consequence / 4. Semantic Consequence |=
10477 |= in model-theory means 'logical consequence' - it holds in all models [Hodges,W]
5. Theory of Logic / I. Semantics of Logic / 4. Satisfaction
10474 |= should be read as 'is a model for' or 'satisfies' [Hodges,W]
5. Theory of Logic / J. Model Theory in Logic / 1. Logical Models
10473 Model theory studies formal or natural language-interpretation using set-theory [Hodges,W]
10475 A 'structure' is an interpretation specifying objects and classes of quantification [Hodges,W]
10481 Models in model theory are structures, not sets of descriptions [Hodges,W]
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / i. Cardinal infinity
10480 First-order logic can't discriminate between one infinite cardinal and another [Hodges,W]
9. Objects / A. Existence of Objects / 5. Individuation / b. Individuation by properties
10194 Two things can only be distinguished by a distinct property or a distinct relation [Black]
9. Objects / F. Identity among Objects / 5. Self-Identity
10193 The 'property' of self-identity is uselessly tautological [Black]
9. Objects / F. Identity among Objects / 7. Indiscernible Objects
10195 If the universe just held two indiscernibles spheres, that refutes the Identity of Indiscernibles [Black]
25. Social Practice / F. Life Issues / 4. Suicide
19739 The maxim for suicide is committed to the value of life, and is thus contradictory [Kant]