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Ideas for 'works', 'Elucidation of some points in E.Schrder' and 'First-Order Logic'

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10 ideas

5. Theory of Logic / A. Overview of Logic / 1. Overview of Logic
10282 Logic is the study of sound argument, or of certain artificial languages (or applying the latter to the former) [Hodges,W]
5. Theory of Logic / F. Referring in Logic / 1. Naming / b. Names as descriptive
21889 'I' is the perfect name, because it denotes without description [Derrida]
21878 Names have a subjective aspect, especially the role of our own name [Derrida]
5. Theory of Logic / F. Referring in Logic / 1. Naming / c. Names as referential
21879 Even Kripke can't explain names; the word is the thing, and the thing is the word [Derrida]
5. Theory of Logic / I. Semantics of Logic / 1. Semantics of Logic
10283 A formula needs an 'interpretation' of its constants, and a 'valuation' of its variables [Hodges,W]
10284 There are three different standard presentations of semantics [Hodges,W]
10285 I |= φ means that the formula φ is true in the interpretation I [Hodges,W]
5. Theory of Logic / J. Model Theory in Logic / 3. Löwenheim-Skolem Theorems
10288 Down Löwenheim-Skolem: if a countable language has a consistent theory, that has a countable model [Hodges,W]
10289 Up Löwenheim-Skolem: if infinite models, then arbitrarily large models [Hodges,W]
5. Theory of Logic / K. Features of Logics / 6. Compactness
10287 If a first-order theory entails a sentence, there is a finite subset of the theory which entails it [Hodges,W]