Combining Texts

All the ideas for 'Reason, Emotions and Good Life', 'Models' and 'First-Order Logic'

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16 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 / 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]
6. Mathematics / B. Foundations for Mathematics / 6. Mathematics as Set Theory / a. Mathematics is set theory
10286 A 'set' is a mathematically well-behaved class [Hodges,W]
14. Science / B. Scientific Theories / 7. Scientific Models
17499 Theoretical models can represent, by mapping onto the data-models [Portides]
17498 In the 'received view' models are formal; the 'semantic view' emphasises representation [Portides, by PG]
17501 Representational success in models depends on success of their explanations [Portides]
17502 The best model of the atomic nucleus is the one which explains the most results [Portides]
17496 'Model' belongs in a family of concepts, with representation, idealisation and abstraction [Portides]
17497 Models are theory-driven, or phenomenological (more empirical and specific) [Portides]
14. Science / D. Explanation / 2. Types of Explanation / i. Explanations by mechanism
17500 General theories may be too abstract to actually explain the mechanisms [Portides]
20. Action / C. Motives for Action / 3. Acting on Reason / a. Practical reason
4316 Either all action is rational, or reason dominates, or reason is only concerned with means [Cottingham]