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All the ideas for 'Propositions', 'Logic and Conversation' and 'First-Order Logic'

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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 / 1. Naming / b. Names as descriptive
Maybe proper names have the content of fixing a thing's category [Bealer]
5. Theory of Logic / F. Referring in Logic / 2. Descriptions / b. Definite descriptions
The four leading theories of definite descriptions are Frege's, Russell's, Evans's, and Prior's [Bealer]
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]
10. Modality / B. Possibility / 8. Conditionals / c. Truth-function conditionals
Conditionals are truth-functional, but we must take care with misleading ones [Grice, by Edgington]
The odd truth table for material conditionals is explained by conversational conventions [Grice, by Fisher]
Conditionals might remain truth-functional, despite inappropriate conversational remarks [Edgington on Grice]
10. Modality / B. Possibility / 8. Conditionals / f. Pragmatics of conditionals
A person can be justified in believing a proposition, though it is unreasonable to actually say it [Grice, by Edgington]
19. Language / D. Propositions / 1. Propositions
Sentences saying the same with the same rigid designators may still express different propositions [Bealer]
Propositions might be reduced to functions (worlds to truth values), or ordered sets of properties and relations [Bealer]
19. Language / D. Propositions / 2. Abstract Propositions / a. Propositions as sense
Modal logic and brain science have reaffirmed traditional belief in propositions [Bealer]