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All the ideas for 'Consciousness, Philosophy and Mathematics', 'First-Order Logic' and 'Reference and Definite Descriptions'

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17 ideas

5. Theory of Logic / A. Overview of Logic / 1. Overview of Logic
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 / 2. Descriptions / a. Descriptions
Russell only uses descriptions attributively, and Strawson only referentially [Donnellan, by Lycan]
5. Theory of Logic / F. Referring in Logic / 2. Descriptions / b. Definite descriptions
A definite description can have a non-referential use [Donnellan]
Definite descriptions are 'attributive' if they say something about x, and 'referential' if they pick x out [Donnellan]
'The x is F' only presumes that x exists; it does not actually entail the existence [Donnellan]
5. Theory of Logic / I. Semantics of Logic / 1. Semantics of Logic
A formula needs an 'interpretation' of its constants, and a 'valuation' of its variables [Hodges,W]
There are three different standard presentations of semantics [Hodges,W]
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
Down Löwenheim-Skolem: if a countable language has a consistent theory, that has a countable model [Hodges,W]
Up Löwenheim-Skolem: if infinite models, then arbitrarily large models [Hodges,W]
5. Theory of Logic / K. Features of Logics / 6. Compactness
If a first-order theory entails a sentence, there is a finite subset of the theory which entails it [Hodges,W]
6. Mathematics / B. Foundations for Mathematics / 6. Mathematics as Set Theory / a. Mathematics is set theory
A 'set' is a mathematically well-behaved class [Hodges,W]
6. Mathematics / C. Sources of Mathematics / 10. Constructivism / b. Intuitionism
Intuitionist mathematics deduces by introspective construction, and rejects unknown truths [Brouwer]
19. Language / B. Reference / 4. Descriptive Reference / b. Reference by description
A definite description 'the F' is referential if the speaker could thereby be referring to something not-F [Donnellan, by Sainsbury]
Donnellan is unclear whether the referential-attributive distinction is semantic or pragmatic [Bach on Donnellan]
A description can successfully refer, even if its application to the subject is not believed [Donnellan]
19. Language / B. Reference / 5. Speaker's Reference
Whether a definite description is referential or attributive depends on the speaker's intention [Donnellan]